wrencher

My mission is to find out if an external filter could have saved this tranny.
About me- certified professional wrencher- but not for this brand
Been around long enough to have seen honda push their CVCC technology as a selling point. So yes I know how to use my wrench!

Even though I see by the posts that most here are DIYers ...i think a few will appreciate some diagnostic/repair info. I'm out to find the cause...not just overhaul. Keep in mind that most of this repair is beyond the scope of "weekend mechanics". but your welcome to try....just baggy and mark down location of the hundreds of pieces in the transmission as you open it

Picked up one of these 7th generation automatic civics with a tranny problem. Intermittent engagement of R D 3 2 and then slip and loss of all engagement after 2 minutes of driving
Didn't know better at the time and figured it was electrical! NO!


So this civic suddenly lost all forward and reverse gears. It has 200k + km on it. fluid never smelled burn't. maybe it slipped a bit prior to total failure - maybe not...guess we will never know.
Fix diagnosis:
Fluid was fully flushed with tranny flusher and it then intermitently would engage D or R .
I read up on this issue and found it was common and internal....but mine was intermitent and when it ran- it worked great shifting points good ect.. Seeked wisdom from peers at other brand--->Guess what??? dealer doesn't even open these transmissions up for service. HAHAHA! Tech suggested to check selenoids so I removed, cleaned, bench tested selenoids. Wasn't the problem. I started to notice a pattern develop: car sits > it engages. car runs > it eventually whines (like power steering pump) and starts to slip then drops the gear. let it sit off long enough and it re-engages. Tightly packed fiber residue on strainer could partially restrict suction. Could it be a blocked strainer (pickup tube filter) could it loosen when sitting? Another post on this forum , of a similar problem and eventual fix, sparked my curiosity. But he changed so much (opted for a full rebuild) I got the facilities, knowledge, and resources, some time....lets play!

The inspection: So I am assuming that it is a blocked strainer. But no pan on this model- and it isn't easily serviceable. I dropped the fluid ( 2+liters)and shoved an inspection camera through the drain hole. guess what: the strainer looks inline in the diagrams ....but i can"t see it with my cam...lots of bolt heads and gears in the way....but no strainer!

plan 2: lets try to partially clean/flush it out in place with brake cleaner (use it all the time to clean valvebodies on overhauls). I blow compressed air and brake cleaner through drain and fill hole. All over the inside, bound to hit that strainer I hope. Messy!...some fiber residue coming out.

fill and run: it engaged! Ran in gear for couple of hours on lift. drop and roadtest... was great for first 10 minutes then poof! Starting to slip... but still engages gear. Took line pressure: low at 110psi and little volume (or internal leak). But the pump is whining so probably not internal leak. Really sounds like a blocked strainer now .

decision: Drop and rip open for inspection:
Was a very easy drop. Opened the case.- Yup, strainer is plugged up with fiber residue. Inspect clutch packs- all in good condition except 2nd fibers as expected are quite worn and metals slightly discolored. 2nd clutch installed clearances slightly excessive so why not change...But not so bad! could probably close it back up with old 2nd packs (but for 24$ oem) Yes Got pics! All seals are good on mainshaft. Was it really the strainer. Cleaned it out ---like new now.( Yes they are cleanable like any other screen!). check valvebody- all good. gonna gamble on not checking pump. my brand requires special alignment tools for pumps...and i have never seen a pump failure to date....only valve jam/spring brakage.

What should i do about the torque????- 50/50 decision here. some of that residue may be caused from the lockup clutch inside the torque. But then again ...never had a lockup code. I'm chancing it! Gotta keep all variables to a minimum .Gonna clean it and try with old torque. Worse case scenario...i need to sacrifice another few hours to put in a new torque if it codes....(and few hundred$$$)
Parts on order. sticking to oem so i don't need to wait for delivery...and recalculate all my clearances/shims. Should be back together by weakend ...maybe if i have time. For sure going with an external trans inline filter also. honda wants $30+ for the one from the Fit....going jobber for now.

Any questions or requests please ask now while it"s open



Not too dirty inside



2nd fibers and steels- slight wear (measured) and glaze from slip



4th fibers for comparison (same part)



After cleaning 2nd steels



No.thats not a new strainer...just a cleaned out one.

scooty

Wow, I think you go beyond the DIY capability of most people here, cracking open that trans. I don't think most of us have ever seen the internals of a 7th gen auto posted on here. Keep us updated!

scooty

Just out of curiosity, could you please post a pic of the torque converter, front and back?

gearbox

iTrader: (95)

wish i had the patience and know how to do this. btw, does that filter mesh extend inside the metal housing where not visible? if so, a new filter would be in order or leave it out if you use an external. the problems on these trans usually involve debris from the weak secondary clutch pack clogging the filter and eventually killing the oil pump. some also have torque converter issues. its interesting that mine only slips (gear 2-3) when cold, yet only whines when hot. ive changed fluid yearly ever since 20k miles and wish i wouldve started at 5k. but i knew literally nothing about cars at that time.

wrencher

Yes... that screen extends all around in an oval within its case. But cleaned it all easy. No, you can't leave it out cause it's part of the pickup tube. It is also the "first defence" against debri going through the trans pump....before it could hit any external filter.


it was very dirty.... too bad i didn't pic it. imagine a black fuzzy looking filter..

cvguy

First off, many thanks for taking the time to write up all of this info. You're right that most of us DIYers will never get anywhere close to this level, but probably there are a few guys here that might be able to swing it. But threads like this and the (incredible) one that johndeerbones did, are really great for helping the rest of us understand exactly what these tranny problems are. So having said I'm never going to try a rebuild, here's a (probably dumb) question on what you wrote above. How much "extra" stuff needs to be done, beyond the drop and open, to get to and remove the strainer for cleaning? Is it just removing a bunch of other stuff, and reinstalling it all back the way it was? Or is this something that an amature has no business messing around with? I really don't anticipate trying to do this, but then again, maybe you could convince me to give it a try

wrencher

Here you go:
unfortunatly not much to see, as all the "good stuff" is inside and welded shut. FYI: Torque converters can be sent out for testing.



transmission side




Know its blurry...If any out there is going to replace a transmission. keep a close eye on that Oring just below the ATF pump engagement splines; it is very important....




flexplate side (motor side)

wrencher

Since many like pics:

The Assembly:


Good view of assembled mainshaft and secondary shaft.

For those wondering: from left side . mainshaft with 4th gear(top below gear) and 2nd gear (bottom) clutch drums. They are stuck back to back on this model. The clutch fibers, steels and pistons are all within those drums.
Shaft on the right is secondary. The single clutch drum (at the bottom) is the 3rd clutch... that bigger flat gear right of that is the differential gear... your right driveshaft pops into that hole in the center of it. that big hole in the case is for the starter motor... that selenoid at the left is the famous torque lockup selenoid!

pay attention to those little holes in the clutch drums...i will be refering to them later in my writeup/conclusions.




Other side . With valvebodies...and a good look at the installed strainer/pickup tube




top view




all around

wrencher

Now we put the center part of the case on and we start assembling the last bit. The Park pawl (lock) and 1st gear clutch.


That toothed wheel and matching locking lever is what locks your car from moving when in Park. In this case its not rounded at all.....so the driver never slamed it into park while vehicle was still moving!

the clutch drum is 1st clutch. on the left










And it's all closed ... and in the car....now the write up. conclusions....opinions

remember ... I inspected/measured all inside...but only cleaned the screen (strainer/pickup tube) and replace 3 not so worn 2nd clutch fibers (24$ OEM). (Also the 2 case gaskets cause you can't save them)...

My mission was to know what was happening to this transmission (and maybe many others). Could anything have saved it?
The results tomorrow...and line pressures etc....need a couple of cold ones now....

johndeerebones

I assume the "other" post was mine. Been a year and almost 40k. Kudos to you for finding that, most guys very lazily search for a topic. To answer your question, yes, an external would help minmize the debris, but not eliminate it altogether. The clutch fibers fall to the bottom of the trans, the filter picks up oil FIRST, then it pumps it through the trans and the cooler lines, where you would put a filter. Atleast you could change it out, so theoretically you would remove the majority of the junk with the external filter. Only prob is that the internal filter as you saw is really fine, not sure what would get through it to the external. To calm your nerves though, the predominate reason they wore the packs out as much as they did was because the clutches were defective. I hope for your sake Honda OEM parts are different. If they are you have fixed the main problem. That and the resultant stopped up filter and no oil flow..
At 200k probably not the case, but a smaller percentage of the TCs had TCCs that would disintegrate and stop up the filter as well. At any rate, the new one from my build was $160-170, so cost wasn't worth the possibility of having to take it out again....

I see a two post in your pic, nice facilities. Spent my last 15 years in a shop, but did my rebuild in my garage floor on jackstands. It was a pain in the butt to pull it, but not because the work was exceptionally hard, just the conditions weren't ideal.

gearbox

iTrader: (95)

its a wonder these things work at all seeing as how complicated they are. one o-ring shrinking a bit and youre screwed. i also heard that another issue on these trans are the o-rings which degrade from the honda atf over time. then they do not seal as well and it reduces fluid pressure and causes slip when cold. but after warmup, the seals swell and pressure is restored so shifting is fine.

johndeerebones

You are right. A new TC is a waste of time and money at this point. Yes it is possible your TCC isn't working, but any slip anywhere while the TCC is engaged will give you a P0740. It's basically a input/output don't jive... The code will not set unless you are above 40 m/h. I tried the solenoid thing too before I new any diagnostics of this transmission. The old one wasn't as strong, but it worked. Have a long enough gauge and hose to install it into the ports and at least run it on jack stands? Preferred to drive it if possible. The values can vary based on load etc.... Go ahead with the compression check as a routine, but I think they must diamond crust the cylinders of these things or something, lol. Mine had 150 or 160k when I did the head and timing belt and it didn't have so much as a wear ridge.... I adjusted the valves and it runs like a brand new one..... Unless you are noticing power loss or burning oil I would highly doubt engine trouble. You were the guy with the original t belt though weren't you? If so definitely figure on replacing it soon. a decade and almost 150k means it is definitely a gamble to not change it.

wrencher

Flushed external cooler, topped up transmission, spun it up on lift and filled all internals, leveled the fluid....


My findings and opinion. (remember these are my personal opinions)

Yes it ran great.shifted solid, yet smooth. Before even roadtesting I hooked up my guage to see if line pressure/volume had increased . Back to spec at ~134psi@2000rpm. But biggest difference was volume- when gear selected, the clutches would fill up quickly. Pressure increase was instant accelerated in any gear.
So there you have it! the internal screen was the culprit. So what caused all this fiber? In all honesty there wasn't that much fiber debris. a little from all the other clutchpacks and a little more from the 2nd. I've rebuilt many "other brand" transmission where 4, 5, 6 fibers where down to the metal, the trans oil looked like diesel oil (black). The smell made me wish i was wearing a respirator.....and yet line pressure was good- no pump starvation.

Are those 2nd fibers defective? NO! I think too many people are using the wrong word. Could they have improved? YES (and i hear they now have a new material?)- maybe to a longer lasting, finer debris material! Simple proof that they are not defective is that 4th clutch uses the same fibers- and they are usually OK.
The big problem to me is that screen is too fine/too small for it's "liftime" use. It should be able to hold at least all the fiber from all the clutches reaching their service limit and still provide adequate passage. It's a catch 22. The partial blockage causes a drop in volume/pressure, some slip occures and the fibers wear out faster causing more blocking material. The harder one drives this transmission the faster this wear happens. All in all not a transmission made for abuse (only 3 little fibers per clutch).
2nd gear also takes the hardest "hit". Driver floors the accelerator from stop. First engages (already engaged) and we are off. Converter spins over torque stall speed- our converter now has minimal slip. bang it hits second gear. the engine is just under redline. The converter has no slip mercy and the engine has spun up so much momentum, the wheels won't give any slip either! That little clutch is trying it's hardest to lock up! That hard work ate at some of it's friction material . it locked. Engine rpm drops! car almost redlines again... already wizzing Past any legal speed limit (unless your on highway). So you back off,,,quick upshifts 2-3-3-4-cruise. Or not...
Hard acceleration city downshifts will also usually hit 2nd hard.

They could have made it stronger/ more discs/revised part- but can the PCM "learn" shift times and adjust pressures accordingly? can a new shift curve be flashed into PCM? (whole other subject-sorry)

So would that external filter have helped? Yes to a certain degree. If finer than the internal it would "catch" some fiber therefore helping the internal keep cleaner. A slightly coarser internal filter screen would be in order. The larger chunks would stay trapped on the internal filter as all has to go by this internal filter to be able to hit the cooler line... (as Bones also stated). Worn clutch fiber and trans fluid gets flushed out through those little holes in the drums (that i refered to in an earlier post) and drops to the bottom of the case. Waiting to be sucked up again through the screen for another spin. Maybe this time it will be the "some" that got to go to the cooler and external filter.

In general clutch fiber has very little problem going through domestic filter screens. Yes it's abrasive by nature and wears down pistons and seals. Maybe that is why they show more wear on their shafts and bores. at 200k km than this transmission. Or is it that this fiber residue is larger?

I say honda should have made a larger, less fine screen, and put an external filter.... Wait! isn't that what they did on the Honda Fit?

or at least some way to clean the screen every so often (a simple threaded hole in the bottom of the case which would lead to "after" the screen" .Air and cleaner would then be sent in to "reverse flush this screen"... yes i was tempted when it was all apart!

Untill then i would suggest: drop the oil in the case every oil change (~3 quarts) and do a complete flush (machine needed) every other year. And drive her easy.



My total bill? original flush (16liters dexronVI and trans cleaner/conditioning ,many cans of brake cleaner (some for original diagnosis) (also to clean dissemble trans).
2 case gaskets (20$)
3 clutch discs (3X $7)
~8l dexronVI (sorry Honda your oil is expensive and was told dexron works ok)
about 10 hours for diagnosis drop and inspection.
Now before all of you run out and expect your corner transmission shop to do this (dealers don't open transmissions?????); Keep in mind that this was a research job- under normal situations the overhaul would be replacing all seals and fibers; sending out torque for testing.

As for lockup codes- I'm assuming that the volume/pressure is dropping just enough for the converter not to be able to "hold" in a lock when comanded. the ecm/pcm "sees " excessive slip between engine rpm and input shaft rpm hence setting code.
I heard there was a TSB on converters- will readup on it
selenoid codes can be as a result of electrical or mechanical failures. Never assume without diagnosis.

PS: normal symptomes of one "worn" clutch pack on "other" brands are usually a flare/slip when going into that gear. Not slip in all gears or failure to engage.
Always follow proper diagnostic procedures before assuming that this is your problem- similar condition/symtomes may be caused by different problems/failures.

So there you have it!
Drive her nice, change her oil often ( flush and also from her drain to evacuate coarser fiber debris), install an external filter- and hope

MEHONDA

RichJ

wrencher
To say I'm impressed would be an understatement. Thanks for the great write up and pics.

Rich

sdaidoji

iTrader: (1)

good god...
these guys simply do not let me keep my strike... Greeeat post!
Lock now before some idiotis start crowding this thread with unrelated question! but keep open for Wrencher to post!

wrencher,

i took the liberty of sharing in other forums too. this deserves it!

good job!

http://www.7thgenhonda.com/forum/sho...838#post818838

http://honda-tech.com/showthread.php?t=3083274

gearbox

iTrader: (95)

great info. i only use defect because that is how honda described the problem with the secondary clutch wear in their own TSB (should have been a recall). i have seen it but unfortunately couldnt find where i saved the file. driving hard certainly would make it worse, but many of us (including myself) drive very carefully shifting under 3k rpms most of the time and still had this problem very early on, sometimes after only 10k miles. i have probably redlined the car 5 times in 100k miles.

wrencher

If anyone can find the original TSB by HONDA claiming that their clutch fiber is defective, i would love to see it! I may just claim some $$$ for my time from them. I don't believe they would make such a wording mistake and admit guilt as it would open them up to easy lawsuits/ recall. If they Had such, They surely made it dissapear effectively. The most manuf. will usually admit to is a "revised part". I checked over all the civics TSB's for the civic 01-05 and found no reference as such to "defective" clutch fiber but rather mentioned excessive wear of 2nd clutch as a possibility for car not moving....etc. (we now know that it causes a blocked strainer- don't we? ).
I think i can also stick my neck out and claim that something changed for 2005 (or after a certain manufacturing breakpoint) as this TSB only applies ~2001-2004. Don't know for sure how much "stuff" changed.

sorry can't fit whole TSB:




Interesting: HONDA also recommends installing an inline filter ?????



here step 13

gearbox

iTrader: (95)

thanks for finding those. i stand corrected, although to me "excessive wear" is not a normal thing. why couldnt they make the second clutch just like the rest of em in there and avoid this whole mess? as for the 2005, im not sure why but they left that year off on lots of things, including the official honda service manual (which also says 01-04 only). but we all know its the exact same car as the 04.

gearbox

iTrader: (95)

also in 13, it says the filter install only applies to cars without an atf warmer (the radiator "cooler" so to speak). every civic i know of has this atf warmer, because the radiator coolant gets hotter than the atf oil and warms it under normal conditions.

wrencher

You are very right in what the "cooler" does on the civic. I never saw one on a honda either (and i'm in the Freezer) so i googled it.

google: 25560-R5L-003 (2012 CRV) or 19430-RCA-A51 (2003 accord)

I've seen these before on german cars too

That install instruction procedure is generic for all their vehicles so I'm sure they are refering to the external model (not in the rad)- I could be mistaken...anybody out there a Tech for Honda ??? Mind clarifying the "fancy" honda vocabulary????

gearbox

iTrader: (95)

as for external trans oil coolers, they only come stock on CVT trans civics (at least for 01-05 i know for sure). and they are not much bigger than the radiator version. those cars also had the external generic trans filter installed from the factory. i used to have one on the regular auto non cvt civic but it really didnt do anything that i could visibly see and possibly may have dropped the line pressures a bit.

sdaidoji

iTrader: (1)

this is as stated from start, a no-question ask thread, just informative thread. No one will answer questions in here.

being able to read is a must to make real use on a forum, actually. speaking out will lead you nowhere most of cases. reading is most important.

sdaidoji

iTrader: (1)

just thought this would be interesting info

http://www.mistertransmission.com/ho...ission-repairs

" Common Issues with Honda Transmissions

Harsh shifting, flaring (RPMs go too high) between shifts, lack of engagement (not moving when you shift into gear), and clunking when shifting from forward to reverse are common conditions experienced when there’s a problem with Honda transmissions. It’s important to remember that due to the complexity of today’s computerized transmissions, that just because the transmission appears to be malfunctioning doesn’t mean the actual problem is in the transmission. Your vehicle’s computer gets signals from up to 32 separate sensors throughout the vehicle’s other systems and any one of these could be sending inaccurate or no information.

In order to save yourself from paying for a costly overhaul that may not be needed, please bring it to the professionals for their expert diagnosis. If you’re experiencing any sort of transmission problem, please contact your local Mister Transmission and book an appointment for our FREE 21-Point Multi-Check Inspection.
More About Honda Transmissions

Honda's automatic transmissions are unusual in that they do not use planetary gears like nearly all other makers. Instead, the Hondamatic and its successors use traditional sliding gears in parallel like a manual transmission. Honda was forced to invent their new system due to the vast array of patents on automatic transmission technology held by BorgWarner and others.

Honda initially chose to integrate the transmission and engine block for its first application (in the N360) as in the Mini. The Hondamatic incorporated a lockup function, which Honda called a third ratio, and had manual gear selection. The company's early transmissions also used a patented torque converter which used stator force rather than hydraulic controls for shifting.

The company's naming scheme is also confusing, as it is specific to a single model of vehicle and some identifiers are reused.

1973–1979 H2 — 2-speed
1979–1985 H3 — 3-speed
1983–1991 H4 — 4-speed (aka AS/AK/F4/CA/P1/K4/L4/PY8A/ML4A/MY8A)
1986–1990 G4 — 4-speed (aka L5/PL5X)
Honda/Acura Legend
1989–1991 Civic AWD — 4-speed (aka MPSA/S5)
Honda Civic AWD
1990–1997 H4A — 4-speed (aka A6VA/AOYA/APX4/APXA/BOYA/MP1A/MP1B/MPJA/MPOA/MPWA/MPXA/PX4)
Honda Accord, Honda Prelude, Honda Odyssey/Isuzu Oasis, Acura CL
1990–2000 Integra — 4-speed (aka MP7A/MPRA/RO/S4XA/SKWA/SP7A)
Acura Integra
1991–1998 Vigor — 4-speed (aka M1WA/MPWA)
Acura Vigor, Acura TL
1991–2003 MPYA — 4-speed (aka MPYA/M5DA/M5HA/MPYA)
Acura Legend, Acura TL, Acura RL
1992–2003 S24A — 4-speed (also A24A/A2YA/A4RA/B46A/B4RA/B7ZA/BDRA/BMXA/M24A/M4RA/M4TA/MCVA/MDLA/MDMA/MRVA/S4RA/SLXA)
Civic, del Sol, CR-V
1995–2002 B7XA — 4-speed (aka B7TA/B7VA/B7YA/M7ZA/MPZA)
Honda Accord, Acura CL, Honda Odyssey/Isuzu Oasis, Acura TL
1996–2003 Multimatic — CVT (also M4VA/MLYA/SLYA)
Honda Civic HX CVT, Honda City
1997–2002 M6HA — 4-speed (also B6VA/BAXA/MAXA/MDWA/MGRA)
Honda Prelude, Acura CL, Honda Accord, Honda Odyssey/Isuzu Oasis
2000– H5 — 5-speed (also B7WA/BAYA/BCLA/BGFA/BGHA/BYBA/M7WA/MAYA/MCLA/MDKA/MGFA/MGHA/MRMA)
Acura TL, Acura CL, Acura MDX, Acura RSX, Honda Odyssey, Honda Accord
"