kinakoes2

Relax -- I've noted the caveats on going outside the FSM in the 'special tools' thread... and all the usual 'info-only', at-own-risk warnings apply on any enthusiast forum. Not my first rodeo... both riding and ridden.

I'm not worried about the Honda FSMs (as they're very, very similar to their excellent FSM counterparts in the moto world), but as a poster on other car and bike forums, often FSMs are the absolute worst way to do anything (*cough*FORD*cough*).

If IMO there's a better (easier to understand, or lower-effort, or both) way to teach someone to complete a task safely and effectively, and I can reasonably confirm it works (the part a lot of so-called gurus leave out before posting advice)... then I stand behind it. If it doesn't work and an asker questions, there's never any danger of 'rep' risk in the first place... but I try to figure out why -- being a tech so long you assume the asker sees things you take for granted, so there's often a disconnect. Bridge that gap, correct mistakes, and carry on. And if anyone wants to withdraw their experienced but hearsay advice from my thread because they won't stand behind it... I'll remove it for the same reason -- sometimes you just have to trust experience, but respect is key.

Doesn't mean shortcuts aren't valuable, as every flat-rate tech knows... but knowing when to use them and not the FSM proc, is what should be stressed prior to teaching someone how to do anything on a car.

ezone

Sometimes we have secrets.
Sometimes we do things in ways that "shouldn't" be done.

Sometimes we might have people at corporate monitoring what we post.




I need to know what the intended goal is before starting a task. I prefer to develop my own plan to achieve that goal.

Like, remove a transmission. I can usually get it on the floor without a book telling me 187 steps to get it there.




I have a huge problem with blindly following orders. I don't think I'd be alive right now if I had done that all my life, and I certainly wouldn't be able to operate at the level I do now.

"Rules are for the obedience of fools and the guidance of wise men." - Douglas Bader

kinakoes2

Oh -- the people I refer to there, are 'gurus' who haven't done the proc, but insist it's the best way. Those kinds of advice are quite dangerous. I try to vet any hearsay (as I can't do every proc) through the most reliable sources I can... but I hear ya on if you're being monitored and there's consequences for veering too far off message.


As would any good tech. The secret to being a tech worth their tools, is knowing the FSM proc inside and out, then knowing where they can save time/effort. Gotta walk before running.


Being ex-military, but also walking out of a few gigs when the boss(es) are insecure/weasel-y pr*ck(s)... I feel I can see the benefits of both ways, when it's the right thing to do. Never had my competence questioned by any employer, if I got the job via my skillset. But if a boss asks me to ignore or alter protocol when it's clearly in the customer's benefit, or questions a legacy of good work because of reasons having nothing to do with the job... see ya.

Now you know why I'm my own boss, in a different industry.

ezone

I was thinking military when I wrote that, there are a couple ex-military people I work with that seem to think everyone should blindly jump when orders are barked and can't seem to comprehend that an individual can think independently. I just can't play that game.


What do you do now?????

Based solely on stuff taken out of context from a few of your other posts, I'd almost guess you are a hand model. (How wrong was that?)

kinakoes2

Yup. There's no excuse for blindly obeying an unlawful order. However, when you don't know what the law is, it's best to tread lightly -- and take notes. That's how you learn a trade... however I equally dislike people who're contrarians for the sake of 'fighting the man' just as blindly.


I'm a deep tissue bodyworker, a Rolfer (SI). Fix peoples bodies. Doesn't make clients happy when you work their bodies with band-aids and greasy fingernails.

Believe it or not, the diagnostic/triage mind from teching naturally transfers into working the human body... just a much, much more complex machine.


Sheezus, the light from that statement won't reach the truth for a million years, that's how far off it was!

kinakoes2

Anyhow... back on topic.

Siphoned the yellow Prestone stuff out of the res and replaced with Type 2 today, right to the full line. As the res only holds about 16 oz, I don't think any that got drawn into the system will cause any havoc.

Ran the car, all seemed fine. More WOT pulls today just to see what happens... nothing, still running stronger than before the extra burp and heater core flush.

Time to get some stands under the car and do my brake bleed...

kinakoes2

So... finally got a sliver of time to work on the car -- however my phone is always with me, and boom... just as I'm about to work on the clutch fluid flush, I get a client.

So with the help of my dad (who wasn't thrilled about driving fifteen minutes for a five minute proc -- not fond of asking neighbors or their spawn for wrenching assistance), we got the clutch finally bled of its air. Not that much air in it... but boy howdy was that fluid f***ing dirty. Like dark green baby s*** broth. Told ya the previous owners couldn't be bothered with maint reminders.

And yup -- the grabbiness and narrow range of engagement, while still engaging higher off the floor than I like... suddenly began to feel very natural . One side effect of this: that slightly fragile feeling I get while trying to hustle this car around in town with the old, chattering clutch, is completely gone. And while there wasn't much air in the line (two BB-sized bubbles... do kids these days even know what a BB is?), the addition of new fluid without all that water in it probably made up for the rest of the progressiveness that returned.

If you see dark fluid in your clutch master... this proc is very much worth it. I'm sure a similar difference will happen with a brake flush...

ezone

THIS is how to generate business!


Whenever I get slow at work, all I have to do is hand wash my car or bike and boom, there's suddenly more work to do.


Did I already ask you about the vacuum bleed/Mityvac?

I didn't look.....does the maintenance schedule in the owners manual mention anything about clutch fluid replacement? I do it along with the brake fluid service if someone buys the service at work.
Clutch fluid will get dark again in a hurry too.

The clutch slave in my truck leaks a wee bit, maybe a reservoir full every other year. It's been that way ever since I got it ..20 freekin years ago. But that little leak keeps the fluid fresh!





Todays work episode: 2.4K engine in an 07 CRV, 260,000 miles, with Coolant in #2 cyl.... appears to be a blown head gasket and probably a warped head from overheating.
Head Gasket alone is almost 12.0. (An engine swap is 8.8 LOL) A few add-ons, an axle seal, swaybar links, and a door latch and we're up to about 16.
I dropped the whole drivetrain on the ground and moved it to another hoist, stripped it down, timing chain off, manifolds off...I'm at 3.0 right now. Gotta pull cams, rockers, and pull head on Mon. AM, measure to see if it goes to the machine shop.

kinakoes2

Yep -- but doesn't the clutch pedal need to be at the floor to crack the bleed screw (otherwise the seals will be in the way)? When bleeding moto brakes or clutches, always just ziptied the levers, and used the screw to regulate fluid flow. Managed get about half a cup of fluid out -- and MAN was it nasty. I just got back from looking for a shower curtain rod to MityVac with, as the pedal only needs to be held at the floor to pull the fluid IINM.


Being that this fluid wasn't changed since probably its first initial service... I believe you. Worse fluid I'd ever seen in a brake or clutch circuit, by far...


Get it, get it! When I was a tech I used to loooove a big-hour job I had tons of experience with. It's like you're printing money, beating flat rate by something like 4 hrs or even more sometimes (and knowing you can do it above standard). To give you an idea of what Honda paid us for similar jobs on their moto stuff... for a CBR929RR head gasket it was 8.0, and for an engine swap it was 5.5 IIRC. Other weird flat rates were 5.5 for a Suzuki Intruder 1400 Twin valve adjustment(!!! But that job was a lanced-boil PITA, seriously)... and 3.0 hrs for a '00 Kawasaki Vulcan 800 TSB about piston contact in the squish band due to carbon buildup... 1) remove air cleaner 2) run bike at 3000 rpm on lift 3) allow to ingest Yamaha (actually said it in the Kawi TSB) Ring-Free outboard carbon cleaner 4) see bike spit a cup of charcoal out the pipes onto a cardboard soda case until done 5) make 2.75 hrs for free.

ezone

When using vacuum or gravity, no I don't touch the pedal. I want the fluid to flow from the reservoir freely through the system. I'll even turn a bottle of brake fluid upside down and stick it in the reservoir so I don't have to check and refill.


If you push the pedal down, you close off the compensating port(s) to the reservoir and fluid can't flow.
(This is how I stop fluid from dribbling while I have brake lines open, stick a hood prop to keep the pedal pushed down.)




My first 2.4 teardown, my first CRV complete drivetrain drop...... Seriously. Never see problems with these, and this failed due to previous overheats (water pump let go last year sometime).

Plenty of experience dropping like this on 8th gen Civics though, for the cracked blocks. Drivetrain is hung about the same, but the 2.4 engine is completely foreign to me.

You win some, you lose some.
You almost have to have an impact gun growing out of your arm to make time.


I really like when I figure out how to beat the crap out of warranty time. 03-04 Odyssey trans recalls, I replaced the trans in half of warranty time on the very first one.

Some days I'd rather skip real physical work and diag the strange electrical and running problems, other days I'd wish for non-stop timing belt and brake jobs. I'm almost sick of stick-on accessories with all the double sided tape......misposition once and it's stuck for good.

kinakoes2

^Ahhh, gotcha... see this is why I have to put on my student hat and not be afraid to ask questions. No tech knows it all... esp with a different class of vehicle. But the overlap never hurts to have lock/loaded in your melon.

Just to tack a bitty-corner of this awesome convo back onto the topic... after changing my clutch fluid, I'd expected a more progressive engagement, maybe slightly less clutch freeplay, and less shuddering when cold.

Know what I got instead? All of the above, plus better response(???), better steering feel, and a completely different steering effort/tracking at high speed?!? And no, it's not my imagination -- been driving this car for over a month with the same weird, overboosted-y feeling when turning into a corner, and trying to maintain track on my lane at 60+. Now the rack feels super stable all of a sudden... I did tighten the lug nuts on the wheels (fronts were loose), but that was days ago. I cannot explain why the car suddenly prefers to get up and go now, both hot and cold, with a friggin' clutch fluid swap. But I'll take it... I guess cars are more complex than I thought? Naaah... but again, I'll take it... no questions asked.

So 8th gens have a block cracking problem? Yeesh -- on overheat, or journal-related? Gawd I hope it's not the latter. And btw, see many 2nd gen Fits? I know their rads are vulnerable to rock hits... ever drop an L motor for an overheat?

ezone

It was JUST clutch fluid. You know damn good and well clutch fluid didn't have any direct effect on steering and suspension.

Almost sounds like the exact opposite of an Odyssey owner that got their crack pipe reloaded in the sales department. (The Odyssey crowd comes up with crack smoking complaints sometimes....Yours is the polar opposite of 'complaint' LOL)

Coolant leak/overheat.
06-08 and a few early 09s.
R engine only, NOT Hybrid or Si.
Thin areas in the casting.
Warranty extension to 10 years/unlimited mileage for qualifying cars.
Probably less than 1% do it. (I can't be kept busy with them.)

Word: https://www.civicforums.com/forums/181-8th-9th-gen/358064-crack-engine-questions.html


80% are rolling garbage cans here. I have no idea why the car attracts that sort of owner. Hybrids seem to have a similar owner group, but to a much lesser extent. Maybe it's just the area I live in, IDK.

Oh so many of our cars are this way.

When I first got my Civic, I'd trail several car lengths, never tailgate. Not so much now.
I need to pull my bumper off and install some black expanded mesh in the lower opening of mine.
Or maybe paint it body color??



No, the head came off pretty easy in the couple cars I have done that to.

I dropped the K drivetrain out of the CRV just because that head is a **** and there's no room in the car. Time spent to get it on the ground is well worth the effort to me, cuts down overall time and hassle for the job greatly.

kinakoes2

Oh I know how it reads... if someone told me this was happening to their car, I'd claim dogpies too. However, that's what's happening. Perhaps a tiny bit to do with slip that's no longer there?

Thanks for the correction on the fluid path, though -- time to bust out the Mityvac. I'm going to assume all four brake circuits can also be bled w/o pressure @ the pedal...

ezone

You mean how the pedal feels during partial engagement/slip, as in upon takeoff?

To me, clutch slippage while driving has everything to do with torque vs. friction coefficient, not fluid and hydraulics, or a cable if it were cable operated, or steel rods and mechanical linkage.


Wait.....Didn't you say your engagement point was high and likely needed a clutch job?

Maybe it's a weather thing.

Yes. Simple fluid exchange is simple....until someone lets the master reservoir run dry. Then it can be a headache.



I'd Mityvac the reservoir empty using a straw if necessary, refill with fresh, then proceed to the bleeding and fluid exchange from the 4 wheels.

Damn, that reminds me I need to do this to my bike again this year.

kinakoes2

So here's a weird twist... just got done trying the fluid swap via Mityvac (also to confirm if my last work with someone pumping/holding the pedal somehow was done wrong)...

The exact same symptoms came back - the grabby engagement high up, the juddering when cold... even the steering feel and shifting went back to the previous annoying quality. I've bled countless bikes just fine with my MV, so there was zero chance my bleed had let any air in. Fluid nice and clear as yesterday coming out, about two resevoir's worth of fluid passed.

So just to get to the bottom of this, spent the $9 and got a shower curtain rod to hold the pedal down, then repeated verbatim how I did it yesterday with my dad, including the number of pumps (3 + hold) x no of bleeds (10)...

Back to the perfect feel - zero grabbiness... just the slightest, faraway "gikgik" of judder when cold, and that teflon-billet shift feel I expect from a Honda manual. Maybe it's a throwout bearing, and bleeding under pressure from the piston takes up the play in this definitely-worn one? Dunno, all theory for me at this point.

Noticed also that bleeding via MV with no pedal pressure, sucked in more air around the bleed screw threads and possibly the tube fit on the nipple, than brought fluid out - took five pulls on the MV to bring out one res of new fluid. Set vac to 25 inHg, and only bled until saw the fluid gargle. Odd for sure - I'm sure a new clutch'd solve the intermittent stuff, can't expect miracles from worn hardware... usually though they get worse, not better.

ezone

Possible it was sucking air in past a rubber seal somewhere in the system, either master piston or slave piston? (Would be oddball, but I've had that happen with wheel cylinders in the past.)

Sucking air around the threads of the bleeder screw is normal and doesn't cause problems because air isn't entering the hydraulic system. The actual fluid port is much deeper than the threads of the bleeder.


Ever drive a 1st generation Miata?

kinakoes2

That's a scenario I consider the most likely, tbh. The fluid in and around in the lines was not only waterlogged to hell but also full of metal particulate, which didn't assuage my fears about the good ol' throwout/pilot but also added perhaps a slave rebuild...


Gotcha -- yeah bikes have pretty shallow ones, not to mention on systems that are expected to function leaned over at near 45 degrees... good to know.

I've had systems pull in air due to gravity, as the screw is higher than part of the lines that take a sharp turn downward... just enough fluid pulling to draw in air around the threads if you're careless about opening the screw too far for too long.


YES -- my sister had a 1.8L NA with an LSD back in the mid-'90s... that little car had no torque whatsoever, but maaaan was it fun to slotcar around SF in... well, when traffic was actually moving. She was a master at parallel-parking that bar of soap just about anywhere there was a shoe's-worth of room. IME that's the best Japanese manual I've ever experienced (an S2000 one I tried in Phx wasn't as nice as the NA).

kinakoes2

Okay - more headway into why my clutch isn't clutching very well...

On a hunch... I looked again at the job and how I did it... no way I could've done the bleed proc wrong (3 pumps + hold w/prop, loosen bleed screw and allow to bleed down, draw through new fluid via raising clutch pedal, x 10). The only uncertainty in it all, was oddly the clutch reservoir level.

Not sure if Honda skimped on materials for the res plastic (my Paseo res was clear even after 20 yrs), but it was frosted white, making the new fluid even harder to see on an overcast day. Figured out you can tap on the res and the movement of the fluid made it visible enough to see its level. And as my intuition guessed... sure enough, it was high when I topped it off shortly after taking delivery of the car.

All the symptoms fit. A too-high fluid level would cause the expansion of the small amount of fluid in the hard line to preload the throwout, causing a slight actuation. Fluid is practically non-compressible, so the res level couldn't compress the air in it during this, since I'd overfilled. This is why it had the judder and the terrible narrow engagement range, not to mention why it seemed to accelerate better - there was less slip happening with the pedal all the way out. The proof would be if I'd dipped a clean paper towel in the res and absorbed any extra fluid over the MAX mark, I should get back the weird but welcome better modulation, better performance cold and when raining (which it did today), and the unexpected better accel and hwy stability.

Yup. Every one of them came back, with the exact MAX level Tried even a touch below the line... no better. So if you're seeing a gleam of fluid around the edge of the rubber bellows when you fill your clutch res... drain out some fluid - it's too high. Tap the res cap threads with a finger to see actual level.

kinakoes2

Hmm... some odd stuff with this clutch once more. Luckily, my slowly-rising coolant tank shens have slowed down and finally stopped. Not sure how long that's gonna last, but I'll take it. Rad level's stayed up to the neck, again at least for now...

I think ezone's suggestion about a leaking seal in the slave is unfortunately panning out... the clutch's resumed its same-old grabbiness. Gonna bleed it once more, same as before (3 pumps + hold + bleed + refill, x 10) and see what it does...

Lo and behold, my oil consumption problems are officially gone (as predicted in great detail in another thread) -- the car hasn't drunk a drop of oil in two weekends of 80% town/20% highway driving, and fuel econ, while not as good as before I put the 5W40 Rotella T6 in (makes sense, it's more viscous at op temp), has risen consistently since I added the RT6 after buying the car in Feb (have topped off with alternating RT6 and 5W20 Mobil 1 High Mileage).

Despite opinions to the contrary, I'll continue to use Mobil 1 High Mileage without the RT6 next fillup, and see if my consumption begins to rise again... my prediction being it will after a month or so of my driving cycle (80/20). When that happens I'll 'dope' the next change with RT6 again, and keep it as a maintenance dosage. Combined mileage from peak to current is 34/33, so it isn't a huge sacrifice to have it in there. And since a jug holds five quarts... should be a long time before I need to buy more.

kinakoes2

Just re-bled my clutch again... found air in there, a few small bubbles... explains a lot. But since I know the air didn't come from the res, there's only one other source, the slave's seal. Better budget for a slave cylinder rebuild...

kinakoes2

Yesss -- still no oil consumption issues.

As I've written before this poor EX had been sold to me with barely any oil on the dipstick and a VTEC oil pressure CEL -- probably was then the rings got stuck, as parts barely got lubrication with filthy oil... so this dumb kid seller probably decided to rob some clueless grandma of $5K, due to a problem he created. Yep, he wanted $5K for a 150K Honda with rust on the hood, gouges in the RR door and jamb, a dented driver's D-pillar, enough dirt on the motor to grow an acre of soybeans, a filthy interior with torn upholstery, a slightly pushed-in front bumper with broken underguard clips, and a steering wheel with core foam showing... lucky it's a seller's market for Hondas on Maui... and no, I didn't pay no friggin' $5K -- he took what I gave him, when I pointed all this out)...

After the first oil change it drank 5W20 like mad (no more VTEC CEL though, duh), which is when I instituted the Rotella-T6 5W40 + Gumout Regane High-Mileage treatments, along with a proper set of good Denso plugs (ouch), a proper '04-'05 EX LAF sensor to rid the final CEL (OWWWWSONOVA ), and coolant level top-off with Type 2 (swap is planned for soon).

That first oil change got dirty super-fast, and consumed a quart in virtually days of driving (much of that was probably contamination from dirty oil still in the engine). Changed and put in another case of fresh Mobil 1 HM 5W20 + 1 qt RT6. Mileage dropped from 34 to 29 though (!!!), so dropped two quarts and added two of plain 5W20 (to keep approx. 1/2 qt of Rotella in there w/o dropping all that pricey fresh oil). Mpg rose to 32... and within a month it made a consistent 33, where I think it'll drop from here due to normal oil breakdown.

The nice thing is, I didn't have to do anything special, as ezone mentioned the best way to clean ring deposits is... just drove it normally. At first the car was crazy-sensitive to oil level being at or above the FULL hole on the dipstick -- one sign there weren't clear oil passages getting cool oil where it needed to be. Now the oil level's hung out for almost a work week with lots of in-town toodling around... so I think my rings are finally working again.

Mentioned I'd switch back to all-5W20 once this change was spent in a few months... but judging from how well the car is running with 1/2 qt in there (still haven't dropped the old coolant yet, which may bring even more gains), I think the RT6 will stay in -- maybe a bit less, perhaps 1/3 qt as a maint dosage, and see if the mileage gain from less thick oil comes with any negatives.

kinakoes2

Another check-in after a long weekend's driving with the car's particular oil combo, this time with most of the driving during the hot midday... oil is definitely getting dirtier, but not a single drop consumed. Dirty is good when consumption is nearly zero...

Clutch did something I didn't expect... since re-bleeding, the level dropped about half the res amount... but the so-so clutch feel didn't change any... what?

Assuming the fluid left through the slave seal, refilled to max and recapped firmly... no change in level yet, and the nice, non-fragile feel returned. Have never had anything like this issue with moto versions of hydraulic clutch hardware yet... so I'm wondering if a hard line might have a leak. But that doesn't explain why I lost half a res's fluid, yet feel didn't change, the whole weekend.

The car certainly wants to be driven, though re: shifting. The trans shifted way better when the car was driven for long, low-load distances. Once I had to bang off a couple of WOT passes though, that went away. Time to swap out the old fluid, I think... perhaps another swap in a month, to get out more debris.

kinakoes2

One note on shifting for manual owners with stock inductions: if you're experiencing a stiffening of your shifts esp at low speed and esp into reverse... don't mess with the linkage first, check your 1) oil and 2) air filter.

When wrong visc/overfilling/dirty oil is in your motor, it increases friction and tends to spin down faster when the throttle is closed, which preloads your transmission gears enough to create resistance when shifting. All other things being equal, this will slightly increase shift effort esp at low speeds when throttle modulation is high.

Resistance to drawing in air also loads your gears for the same reason: the pistons drawing in intake air encounter more resistance, which takes energy from the spinning crank to overcome, slowing the crank faster. Have both conditions in your car, and they can combine to balk shifting, esp downshifts and shifts into reverse.

I just changed mine, and shift quality at low speed got much better, esp into reverse.

Have a feeling this isn't much of an issue on 7th-gens with aftermarket inductions & cone filters, as they have less intake restriction (from double the filter area... though eventually it would, just not as quickly as the OEM postcard-sized filter area). The oil issues would still apply, though.

pjb3

I have a feeling this is more placebo than anything. As oil gets old the viscosity improvers break down so if anything the viscosity becomes lower not greater. I doubt that the engine decelerates faster with old oil than new. As far as the air filter, when you shift you usually have your foot off the gas so the throttle is closed. At this point the throttle plate is blocking air flow, not the air filter.

Neither should make any difference with reverse since most times you are at idle when you put the trans in reverse.

Increased resistance going into gears is usually either synro wear of the clutch is not releasing 100%

kinakoes2

That's interesting. Then what is your take on why the trans shifts better, after an oil/filter change with an air filter change? My force of will can't be making clunky into billet-Teflon-smooth, I'm a skeptic. :P

We'll have to disagree with visc improvers, as in my case, there are far more than with the typical owner, as I run a half-quart of Rotella-T6 (synth diesel engine oil), along with the rest the usual 5W20. I can feel the grit in the oil and smell the carbon particulate, though the viscosity of the oil itself (at least with the non-scientific and subjective method of feeling both between fingertips) is little changed... and certainly more than the same mileage on just 5W20.

The throttle plate is closed when shifts are good, as well -- the sequence of events and parts involved haven't changed, except for the oil & air filter. This is something I'd noticed when I swapped my stock SV650 air filter for a K&N on my bike, and that has a completely different throwout mechanism, throwout clearance, freeplay, transmission gear type (dog/slot vs. synchro) and even the mechanism itself (cable vs. hydraulic). I'd like to hear your take on why changing an air filter causes the same effect on two vastly different vehicles (one which specs 5W20, and the other 10W40).

Mine is that when the engine can't get air, vacuum goes up -- even at idle, and on any four-stroke IC engine. That means the crank loses more energy during any piston's intake stroke, decelerating during that number of crank degrees, increasing gear face pressure for engaged gears in the trans, which has its non-trivial mass of the wheels and arguably the forward motion of the entire car (in whole, this is known as a pumping loss). Reverse isn't applicable on a motorcycle... but the additional layshaft and gear involved in a car trans would explain an increase in friction, and why it's more sensitive than the forward gears to a change in intake air resistance (again, pumping loss).

I do know how to bleed a Civic clutch, and it's disengaging all the way during my shifts... I'm also a religious 'end-of-clutch-travel' shifter with my bikes and cars (mostly from dealing with constant-mesh trans from the moto side with minimal throwout and as many as eight clutch friction discs). Can't be synchro wear... otherwise the trans would shift exactly the same before and after the changes.

Been able to consistently detect as little as a 1hp change on the dyno on my racebike, due to changing the chain... I'm used to working with very small variables. Perhaps there are those not caused by what I think they do, as car drivetrains are far more complex variable-wise than moto ones, and I acknowledge that. I understand the placebo effect is in force with any subjective explanation for why things happen through feel, but I'm not sure this is as valid on several different vehicles of different types with different spec'd lubricants and clearances from different manufacturers when the changes and outcome is very similar.

Perhaps most won't care as they can't feel things themselves, in which case just disregard this particular tip and seek your own solutions to shift quality.

kinakoes2

Another week with the same 3.0 qts Mobil 1 HM / 0.5 qts RT6 oil combo... another weekend with no oil consumption.

It's been a while since I've owned a car that did that (last time was ~2003, a year and half before moving PHX -> SEA with hundreds of pounds of my shirt dogpiled into my '92 Paseo)*. Put a bit of oil into my Paseo for seven years and my ornery Escort for 1.5 years, every tire fillup (which btw is a lot better when you have aluminum rims, apparently -- both the Toy and Ford had steelies which will always have rust issues in the bead area).

Clutch issues have settled down a bit; it's been awhile since it juddered at all. Still been noticing a teeny bit of consumption at the res though... so need to rebuild that slave cylinder. Far less than it was leaking in the beginning with the crud in the system, however. Also... steering feel's been improving steadily, but there was little diff after oil/filter + air filter change last week, so not sure what's behind that. Mpg went up a bit, to a genuine 35 now (212 miles at half-tank), just more clean fortified lube and less charcoal in plain bearings takes credit.


* Car was never the same after that trip, though it did handle way past prudence gracefully. Btw in 2003 it had well over 130K. And I might add, a 4V head that worked fine all 280K miles I owned it, without a single head gasket failure, even with a bad overheat... with non-TTY head bolts. Not sure if head gasket is graphite or MLS, as Ishino doesn't specify.

pjb3

I do feel there are things that can affect how a car feels. Changes in temperature, barometric pressure and humidity all affect how well an engine runs. Most of the time people don't notice any difference but have you ever felt sometimes that your car just seems smoother, quicker or just runs better? I think electronics have evened out the performance from the carburetors I grew up with but differences are still there.

To answer your question regarding the air filter, I doubt it makes a difference. For a new filter (K&N) to reduce the pumping loses would mean that the filter it replaced was restricting air flow. Any filter that was restricting air flow at idle would be so restrictive that the engines would not be able to rev above idle or at least be undriveable.

Oil is not as simple. Regular oil has viscosity improvers that break down and cause it to thin out while most synthetic oil does not have VI because the base stock will stay in grade over the temperature range. Synthetic does shear so it will change, just not as much. Oil can make a difference, years ago I was talking with one of the tech from Group 44 Racing that used to race British sports cars. They found that Quaker States energy savings oil gave them 5 more horsepower in the v-12 engines. Given the amount of bearing and friction surfaces that made sense. I do believe oil can make a difference but in your case I would be surprised. Given your background I would doubt that you run oil anywhere near the point where the viscosity has changed dramatically or the additives are worn out.

My question would be how much difference in RPM do you think changing the oil or air filter would make? I don't have an answer but I would guess it would be minimal. Since people don't always shift at exactly the same speed and rate each time I would think that would produce more of a difference engine speed. Sometimes you just match engine RPMs better than others or the gears just mesh cleaner.

I can't say you are wrong and I'm always open to rethinking my arguement. People know their vehicles better than anyone so I would be interested in if you notice the same difference next time you change the oi or air filter.

As a note, I changed the oil in my Toyota last week and when I started it I remember thinking how quite and smooth it sounded. I also did not pay attention to how it was before I changed the oil so I don't know if it really was different or not.

kinakoes2

I'd like to mention before anything, that I enjoy a good debate with those that know more than I -- as long as the debate concentrates on sharing knowledge. I have (as ezone has mentioned himself, another good resource here) just enough engineering background to get me in trouble, and a lot of years wrenching and riding. I don't discriminate with those that do not have these qualifications but it does often help keep the sharing part honest.


Agree. Subjectivity is always a factor when it comes to human experience. I'm a deep-tissue bodyworker by trade, so subjectivity not only can cloud the truth of what's going wrong... but can often replace them by directly affecting the structures in trouble (luckily, your Civic isn't part of your body ). Not surprisingly, much of the filter I have regarding signal:noise with feeling what's going on in a body, came from racing, and the (much) simpler variables involved in interpreting a feeling of 'hmm... that's isn't right'... and if it matters or not.


What's important here are two factors: 1) it's the delta between the stock filter's flow and the K&N that's important re: shift mechanisms, and 2) the amount of additional pressure on gear faces a small change in pumping loss can have.

Remember that the D17A2 has only four intake valves open at idle. This means intake air resistance at the valve seats has doubled... which is why when the intake air does reach max velocity at the seat, it's far higher than with four valves open, promoting greater charge mixing (allowing engineers to be able to optimize the head more for max efficiency during full valve opening, without hurting emissions or requiring a larger cat).

The amount of energy the idling crank needs to give up to this resistance is greater, which will vary the speed of the crank during each rotation (slows down more during intake stroke). With both dog/slot and synchro transmissions, the ability for the dog to slot in or the synchro to match gear speeds, depends on less variation in the input shaft, not more. Variation in gear face pressure is fine when you're trying to disengage gears, but not when you're trying to do the opposite. When the air filter is dirty and ready to be replaced, its max airflow ceiling reduces to point at which these variations become great enough to affect pressure on gear faces (not to mention the stock air filter area isn't much bigger than the waffle I had for breakfast this AM... another production compromise). K&Ns have both less resistance to airflow (which reduces their filtering efficiency, DDers with K&Ns in their cars!) and more filtering media area -- which removes more resistance, varies crank speed less, and allows smoother engagement.

This is what I believe is responsible for what I'm detecting, as both the changes I made (oil/filter & air filter -- overall friction and intake air resistance) affect the suspected cause equally.


Agree again, just refer to ezone's conversation about oil we shared on another thread.


Yes, in short. However, my Rotella-T6 synth does have VI in it -- it has to, as diesel engines ask much, much more performance of their oils than gas IC cars will. Every petroleum lubricant will shear eventually out of specified use, however due to the consistency of the HC chains in synth oil, there are far more long ones to shear, thus a longer life cycle for each chain per duty cycle, vs. dino oil. Since stop-and-go driving and its variations of rpm and temperature are harder on viscosity than racing, with rather predictable conditions and constant circulation (not to mention, a shorter exposure to service before changing), we'll have to disagree on which conditions warrant a swap more (plus my last oil change was only the second in a month in an engine that was so low on oil when it was sold to me, that it didn't register on the dipstick).

Another factor was that I'm using Regane in the fuel, which will load the oil with more liberated carbon from the head, pistons and rings than without.


Depends on what you mean by 'difference'. Enough to equal one horsepower? Probably not. Enough to affect shifting in a trans with a leaking slave cylinder seal, extremely-worn clutch disc and flywheel and 150K miles of wear on gear faces and bearings, enough to affect shifting? Probably yes.

I do, every time. Change happens so slowly with oil that we think things are fine... up until deterioration crosses a vital point at which sensations tell us it's not. However, I've been conditioned over time with powersports vehicles and their much smaller displacements, to recognize and sensitize myself to smaller units of change. However as mentioned above, it may or not matter with cars and their larger and different drivetrains -- that's where experienced techs like ezone and others here can help me go back to school. In the case of shifting with a well-worn manual Civic EX though, I think my observations, conclusions and esp tests, have merit.

ezone

My AADD kicked in trying to read all this.


I can see where AF and oil in a bike can have an effect on gearbox shifting and all that if they share a common case and lube......

In a car, all the engine oil and filtration have absolutely no bearing on trans shifts beginning at the moment you push the clutch pedal down.


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Since most of us don't run our cars on a track at WOT for hours at a time.....
Pumping losses begin at the throttle plate, it takes a lot of energy to create manifold vacuum. As long as the air filter can flow more CFM than the throttle, the throttle plate is the limiting factor.
Some manufacturers use EGR to reduce pumping losses (so throttle can be opened more), instead of using EGR for an emissions control.

BMW has "Valvetronic", no throttle body---it uses variable valve lift and timing to control the engine instead of a throttle plate. Eliminates pumping loss?

kinakoes2

Moreso, since a multiplate clutch still has the considerable parasitic viscous power transfer through the oil between the plates to cause torque pressure on gear faces (leave any frontline sportbike on the rearstand, and start it in first with the clutch in -- the rear wheel will spin, quite quickly when cold as well). This is one reason why dog/slot ratio selection is used in moto gearboxes -- because 1) they can shift with power still being transmitted into the input shaft (indirect drive trans with an input and output shaft with gears constantly meshed, unlike a car trans), and 2) the arrangement to get a synchro'd trans' shafts to work with a multi-plate clutch, would result in easily double the weight and much more bulk than the same version with dog/slot and shift forks.

Ah, but we've covered this. It does affect how fast the input shaft is spinning at the moment the clutch is disengaged. There's considerable mass in the input shaft assembly, and how fast the crank is spinning at the moment of disengagement, at any rpm, will affect synchronization.

Let's put it this way: would you rather design a synchro mechanism, that assumes for a constant-speed crank, or one that varies every 90 deg of crank rotation (it an be argued that most inline-4 cranks do that anyway by design, but pumping loss will vary it even more -- just ask the engineers who designed air crossover ports into the GSX-R1000 and ZX-10R cases to allow smaller and lighter clutch and trans components, through less crank speed variance. Pumping loss is a thing -- much more under the pistons than atop it... but any 1000cc engine that has an air filter area easily triple the size of the D17 OEM element, won't have to worry too much about it!).

How this ties into shifts, means you can't assume that input shaft is spinning one consistent speed when you disengage -- this variance will make each shift slightly different. Add 150K of wear and radial play in the gear sets and shaft bearings, and it will play a role. I'm not advocating this thing will destroy your trans, but since I didn't recommend swapping trans bearings in my advisory post to fix this problem, but the much-easier oil/filter/AF, it's just a way to easily get back a bit of proper shift feel.
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Shifts are fine when the air cleaner is fine, throttle closed... as Honda designed it to do. But when the tiny stock filter element chokes up (and mine had sugar cane ash and red dirt in it), it'll increase vacuum even more in a condition (idle throttle position) that already restricts flow to a tiny fraction of WOT CFM.

Air cleaner dirty, oil dirty... shifts crappy. Air cleaner dirty, oil clean... shifts slightly better but still balky. Air cleaner clean, oil clean -- shifts beautifully. Bled clutch and adjusted res levels several times in two weeks to get acceptable shifts before oil/AF swap, zero for a week after. Coincidence? Not sure it is. You're welcome to offer an explanation, that's mine.

Not all of it (actually the double VANOS is separate from the VT logic, even has its own control CPU) -- VT-equipped motors still have a throttle plate, needed to make intake vacuum for emissions components, and locks WOT during operation. But even so air still has friction against the inside of the air path (boundary layer separation as well as intentional turbulence, venturi narrowing to valve seats for velocity, unavoidable production compromises with materials and machining, etc... and of course, the air filter)... but the losses they're eliminating aren't trivial (15% fuel savings... it does make a statement that VT isn't used on all BMWs however, just the luxury V8s and V12s that aren't performance-oriented -- VT doesn't like to work above 6500 rpm). It does demand closer oil change intervals and is much more complex and expensive than a conventional TB-equipped roundel engine.

However, a dirty air filter will still rob energy from the crank at idle lift spec and idle crank speed vs. a clean one... just much, much less than in our Civics with a throttle plate AND a barely-adequately-sized OE-spec dry filter, in the way.