7thgensurvivor

Hey all,

I am in the middle of a pretty major overhaul including timing belt, cooling system, engine head resurfacing, etc, see here:

https://www.civicforums.com/forums/3...50k-miles.html

I think I've decided to go ahead and do a full valve job while I am at it. I'd like to get the valves cleaned up and make sure they are seating well in the valve seats. Plan on hand lapping them following this as a guide:


To get started, I need to get the cam pulled apart and make sure I know how to get it put back together. Been looking for a DIY on this for my 7th gen, but no luck yet. Any pointers? Any thoughts on whether I should replace valve springs, or anything else while I am in there?

Thanks in advance!!!

ezone

IF it really needed attention, I'd have the machine shop do it while they have the head for the other machine work.

Labor-wise, they are far better equipped and far more efficient and experienced at that sort of work than I am in my shop.

7thgensurvivor

Thanks ezone, so glad you are on this forum. I have learned so much just by reading a number of threads where you have shared your experience and hard earned wisdom.

Unfortunately, I am planning on "machining" the head myself, leveraging a lot of learning from other DIYers. Inspiration:



Yes, call me crazy. I have thought about this a lot, and I believe it will work well if I approach and proceed with caution. Feeling pretty confident about this part.

The area where I need help is figuring out how to get the valves out and back in, and determining if I need new springs.

ezone

OMFG I sure hope you are not going to DIY resurface the head. Have a qualified machinist do it. The head needs to have a finish that is almost glass smooth in order for the MLS head gasket to seal correctly.

If you want it done right, pay the man that can do it right.

If the head measures as flat within specs then DO NOT TOUCH IT!

(was that extreme enough?)

If you want to play around, do it on an engine that doesn't matter and doesn't have to live a long life. Like I could send you my ex wifes car.






Valve spring compressor....and the right adapter.

A good machine shop should have a valve spring tester, they should be able to test and tell if the springs are fatigued.

I haven't witnessed valve spring breakage, so that's a plus.

7thgensurvivor

LOL. I knew you would say that ezone! That is why I hesitated to mention that before.

This car with 250k miles on has a value lower than the cost a machinist would charge to resurface it.

I will check for flatness using feeler gauges and a metal straight edge. I assume it needs to be refinished / resurfaced as I was getting coolant in my oil.

I have a ton of respect for your opinion. So don't take this the wrong way, but why do you feel so strongly about not machining it yourself?

If I were to use a 1/2 inch or thicker piece of float glass, and self adhesive 2-300 grit sand paper, I would think I could get the head surface perfectly flat with a very small roughness average. I could be fooling myself.

Problem is, it would be cheaper to buy a JDM engine with 40k miles from Japan than to have someone machine this for me. Unfortunately, I don't have a friend with a machine shop. (Come to think of it, I may. So I will see).

Anyway, I don't take your feedback lightly. Have done a lot of reading on this topic. Still can be swayed.

Thanks!

7thgensurvivor

http://www.practicalmachinist.com/vb...illing-220731/

An interesting thread on this topic...

ezone

Yeah but in this day and age almost anything that rolls under its own power is worth a grand.


Doesn't sound good. Was it overheated severely?
Thanks....
If it is warped severely, it could be scrap. There's a spec for how much material can be machined.
Max warpage EDIT: 0.05mm (0.002")

Total height of the head should be measured to see if it is able to be machined. If it's already been cut in the past, it may turn out too thin.
Head height spec in my info says
92.95-93.05mm or 3.659"-3.663"
That allows a total machining limit of 0.004"?

If it's warped too much and you machine it flat anyway, you could snap the camshaft.
If the bottom of the head is warped, so is the top and so are the cam journals, they are no longer in a straight line.
The cam is cast and brittle, it can't run in a hard bind for very long.

If it's severely warped, a good machine shop may be able to "bake" the head flat again (bake it in an oven while clamped to a heavy flat steel plate, so it straightens and then any machining needed will be minimal)

IF you can get it flat then the rest is about the surface finish.

I've had so many problems with the last remaining local automotive machine shop here, I am now sending head work to another shop in the next big town almost an hour away, JUST so we can get a good reliable product I am comfortable with and we can stand behind (warranty) without fear of a comeback.

Prior to this some heads came back with a belt sander type finish....and the boss refuses to send them to another shop to correct the problem.
I had taken to coating the head gaskets with Hi-Tack to help them seal. I still cringe when one of those rolls in, I always gotta see why and hope it's not because of another head gasket problem. It might not come apart since I glued it down LOL
I'd want to go down to .....maybe 1000 grit wet/dry? I can't tell from here, I'd have to feel it LOL. Finish needs to be damn smooth, 300 sounds rough.

Look at the finish on the head when you get it apart, then duplicate that finish as best as you can. You can SEE the machining finish but you can't feel it with your fingernails. The head gasket coating is pretty thin, it can't compensate for much in the way of machined grooves or imperfections.
The block deck should have the same smooth finish, if you need a comparison. I clean it and the head with a single edge razor blade and spray brake cleaner.


Then you gotta get the thing clean. No leftover grit. Any grit that gets into the oil passages can cause damage.
It needs a head gasket too!

Thanks.
Sorry, I may be too negative, I'm always thinking and posting in "shop mode", where flat blocking a head would never be done. I don't always consider or even want to consider other ways things can get done, nor consider what some are willing and able to do.

If you think you can do it and do it well, go for it.




EDIT
Speaking of paying the man that can do it right, I just paid a lot of loot to have my central AC and furnace replaced. I might have been able to DIY a good part of it, but it could have taken me weeks to do it.

7thgensurvivor

Ezone,

Thanks for the very thoughtful and thought provoking response.

This car was purchased brand new by my dad who had the oil changed with non-synthetic oil every 3,000 miles religiously. It's been well cared for. I took over about 70k miles ago.

Overheating started recently. Not sure how extreme it was, hard to tell. It was loosing coolant I assume through the exhaust pipe. To be honest, the blown head gasket test was not conclusive. I rented the test from autozone, and the tube with the fluid melted when I put it over where the radiator cap goes. I am not certain that the head gasket was blown. When I took it out, I didn't see any tell tale signs.

One thing I am fairly certain of is that the heater core is blocked. When I turn on the heat, no hot air comes out and the engine temperature gauge goes up rather quickly / steadily. I am putting in all new hoses, and planning to remove / inspect the heater core and possible replace or flush it.

I like your recommendation about matching the block mating surface to that of the head. I am certain the head has never been off the block before as I have all the maintenance records. I was very careful when removing it, a quarter turn at a time in the correct bolt pattern. I expect if there is any warp to the head it will not be severe. I'll post a video of me testing it out with a straight. Won't be for a little while though as I won't be able to work on it for a week or so.

I've been reading more about the self machining and seems there are much better materials than sand paper. I need to do a little more research.

Just out of curiosity, what would you expect would be a fair price (ballpark) for re-machining the head? How much more for checking the valve springs and cleaning up the valves and reseating?

Really appreciate your advice.

ezone

There is a water valve that shuts off coolant flow through the core completely when the temp control is set to cool. So the heater core is effectively blocked.

Now what would a blocked core do?

An air locked core and/or low coolant level also could produce little or no heat.


I did not recommend to match them (sanding both)

I meant to stare at the block deck surface finish (as the factory had machined it) and compare your head work to that.

The block deck has been quite robust IMO, it's always been straight on the most severe overheats I have checked.

Call a few places and ask.
I'm not sure what we get charged (as a shop).

7thgensurvivor

Yes, I kept coolant with me at all times and made sure it was topped off. I still was able to replicate this condition where whenever I turned on the heater, the engine temperature would go up and no heat would come out of the vents. Someone convinced me this was the heater core. When dismantling the engine, i semi-severly crimped one of the two pipes coming out of the firewall that goes to the heater core. Not sure if these are part of the heater core or not. Thinking to take it out and verify at this point. Especially cause I have nearly everything else out

Yes, that is how I understood your previous comment. Sorry if my reply was not clear. Good idea either way.

Will do.

ezone

You have the two heater core pipes or hoses sticking out of the firewall..
Use a garden hose to check flow.

Redneck_cdn

A close friend runs the local Machine shop that does all the regional dealer work, When I pulled the head off of my 04 with 260,000kms on it due to overheating, he recommended not doing the valves or even valve seals. Out of the 1000's of heads his shop has seen unless the timing belt broke and bent valves, they rarely seen a head that "needed" valve work done on these motors.

The finish on the head was mirror quality when done properly, carefully clean the block mating surface and good for another 250000kms.

With the heater core, chances are that with air in the system due to the failing head gasket there will be no coolant flowing to the heater core at low RPMs due to the location of the heater circuit. As suggested by the "E" check for flow or try to flush in both directions with a garden hose before firing the parts cannon at the car.

With the head off, check the condition of the coolant transfer pipe on the rear of the block, below the head. I live in the rust belt of southern Ontario and mine was rusting badly and I replaced it easily while the engine was torn down.

7thgensurvivor

Thanks for the info and advice. Not sure I know which pipe you are talking about. There is one that goes directly in to the water pump area. Is that the one? Mine looks good from the outside. Good to know a valve job is rarely needed...

I assume there is no danger in turning the cam sprocket once the head is off? As long as I put it back to TDC before putting on the new belt?

7thgensurvivor

Will be doing this over the weekend I hope, assuming I can fix the crimp in the upper hose.

Redneck_cdn

If the transfer pipe looks good on the outside, should be good to go. Mine had serious rust scaling and was replaced for preventative measure.

ezone

The big fat black coolant pipe that runs along the back of the block under the intake, leads to the back of the water pump.

In Canada the pipe rusts out.
I'm in the rust belt and I haven't seen one do it yet here, but I've been looking harder since I heard about it..
I think I saw one old late 80s Accord rust the pipe out many moons ago though.

7thgensurvivor

Well, I took your advice ezone, and took the head into a shop to have it remachined and have have a valve job done. To my surprise, the price they quoted was very cheap! $30 bucks to have the head machined, $120 for a complete valve job.

So I expect to have a nice shiny head on Monday.

The problem is I don't know how to get the block to look the same. The mounting surface for the head gasket on the top of the cylinder head walls are black and covered in gasket material. I tried using carb cleaner, brakekleen, etc and I can't seem to get it clean. the walls are so thin, that a razor blade feels like it will just cut up the surface.

Any recommendations?

7thgensurvivor

Was thinking about using scotchbrite discs like the one found in this forum:

http://www.bobistheoilguy.com/forums...Number=2740128

I attached a couple pictures of the discs I am considering using. I have read that these discs do not scratch or remove aluminum, but then I have also read the opposite.

I've also attached a picture of the area I am trying to clean
For reference

ezone

Single edge razor blades or a real sharp gasket scraper only. You might want to get a box of blades.
Crab spray if you want.
Minor scratches that are visual aren't significant, but if you can hang a fingernail in a scratch it may be.

On a 7th gen D17 head gasket all that's there is the black coating, just scrape it off. Around the cylinders there may be carbon buildup, just scrape it flat.
You don't need to get all the dark color out, just scrape it flat with a razor.

NO POWER TOOLS, NO SCOTCHBRITE, NO ERASER DISC, NO SANDPAPER!


Leftover grit can get in and ruin bearings. Seen it happen more than you want to know.

Power tools can and will damage the surface, and can remove steel and aluminum leaving the surfaces wavy and no longer flat ---and impossible to seal.

ezone

Ya, that sounds cheap. I hope the freshly machined surface turns out glass smooth, not like it got hit by a belt sander.
You can't make it look the same, don't even try. Just get it scraped clean and flat.

7thgensurvivor

The machine shop is supposedly pretty good. Recommended by a local mechanic that I trust. That is where he takes his heads apparently. Will upload a pic when it is done.

Did a little bit of work on my block with brakeclean, and a little wd40 on high grit sand paper and hand working the top of the cylinder walls. Didn't put much pressure, just enough to break into the gasket material.

Attached pics of how it ended up. Looks pretty decent to me. Thoughts?

7thgensurvivor

One last really important technical question about fluids, then I am done for the 4th of July.

Ezone, what is your favorite drink, beer, spirits or otherwise? I'll need that and your mailing address please.

ezone

Looks clean. Hope it's not TOO clean.

It always scares me seeing people do this. You almost have to remove some metal to get it that shiny, and it doesn't take much effort to remove enough metal to cause the new gasket to not seal correctly.

Gave it up for Lent.
Mostly water and an occasional Gatorade these days. Pepsi is now a luxury in my life.

Maybe you'd like to pay my cable bill instead? Power bill? LOL

7thgensurvivor

Could be too clean I guess, hopefully not. I did the majority of the finishing touch with brakleen. Only time will tell I guess.

xRiCeBoYx

iTrader: (22)

First time I took a head in to get resurfaced, dude told me he could charge me to hot tank it or use brakleen to get the crap off. Another guy at the same shop told me to use marvel's mystery oil to get the heavy crap off. I only go to that machine shop now.