Thread: Engine Reassembly Help.. L67 lots of pics

​So i am finally putting back the engine together to stock form all i wanted to do was replace the gaskets from the heads up and took it apart from till there, i will be doing oil pan as well but for now i want to put it back together up top.
This is my first time putting heads back on usually i never take em off since i dont know how complicated it is. I already have the head gaskets and everything else needed, i am putting back together a stock L67 on a gtp to sell soon and keep my other two 40th's. I can put the rest without a problem i have done so already its just the heads i worry about. since i've heard a lot of stories of leaking coolant, or didnt seal right.

1. Do i put copper spray on the head gasket? i have the felpro gaskets.

2. How do i know which push rods go were i took them out to clean them and idk were to put each of them or if there even different in size?

3. What do i use to clean the surface of the heads and block? degreaser?

4. One of the heads has a small chip by the valves should i worry its a junk yard pulled motor from a 97 gtp.

5. I have the torque to yield bolts for it with a paste on them idk if those are ok for the heads, since i've heard debates about paste and teflon tape and i dont want my heads leaking coolant or anything at all.

6. Any other info is appreciated and thanks in advance.

The car i pulled it out of









The small chip



cleaned the pistons up the best i could.

1. Do i put copper spray on the head gasket? i have the felpro gaskets.
Go for it. Some people swear by it. I always use it on a rebuild. Don't spray the deck or the heads, just both sids of the gasket then install.

2. How do i know which push rods go were i took them out to clean them and idk were to put each of them or if there even different in size?
Always put them back in the same holes they came out of. The wear pattern on the tips are particular to each rocker and lifter.
There is no way of telling what hole they came out of it you mixed them up.

3. What do i use to clean the surface of the heads and block? degreaser?
Razor blade and some MEK or acetone.

4. One of the heads has a small chip by the valves should i worry its a junk yard pulled motor from a 97 gtp.
Take a Dremel tool with a barrel sander and knock the edges down. If you don't do this it will create detonation in that cylinder.

5. I have the torque to yield bolts for it with a paste on them idk if those are ok for the heads, since i've heard debates about paste and teflon tape and i dont want my heads leaking coolant or anything at all.
Put the bolts in and TTY them. They already have a sealer on them. Make sure they are brand new OEM fasteners.

6. Any other info is appreciated and thanks in advance.
If the motor was running well when you disassembled then there should be no problem but to be safe take the block and rods to a machine shop and have them checked for OOR and mains alignment. If the block is out of spec it may run for about 5 minutes and FAIL.

1. will do i have some already
Good choice.

2. Thats the problem i did mix them up when i cleaned them so how can i solve this?
I can't help you here.

3. What about gas?
Don't use gasoline...Benzene is a carcinogen.

4. just slightly? never done work on heads to scared of disrupting any air flow or causing problems with the heads since ive heard its a delicate process
Just knock the sharp edges down without disrupting the valve seat. Smooth is good.

5. Got them from O'reilly also isnt there a torquing procedure at 90 Degrees?

Reference: 3800 Torque specs
Cylinder head bolts: 37 ft/lbs + 130 degrees + 30 degrees up to 10/98
37 ft/lbs + 120 degrees

6. Trying not to put much money into i will be taking the oil pan off to see if there is any material in there but so far it seems good. Also according to a friend i have at the junk he said it was running before they pulled it in.

If the engine was running good before disassembly then it should be good to go but there is a risk involved. Do yourself a favor and go buy a small bore gauge and make sure the rods and mains are less then 0.0005" OOR. This is one the most overlooked aspects of rebuilding the 3800 SII and usually results in immediate failure of the engine. When installing the crank shaft make sure it spins freely. Check the clearances on all mains at the same time and make sure they are all equal. If they are not equal then this means one of three things of which all/any one needs to be addressed:

1) The block is twisted
2) The crank shaft is bent
3) The mains are OOR and block needs to be align honed

Trust me; not making sure that the bottom end is in spec will likely result in immediate engine failure!

$1. I do this as well, use 4-5 decent coats per side. Only spray one gasket at a time. The torquing process will slow you down.

#2, Just put them in. I often have people hand me used parts and ask for the engine to be assembled. Haven't had an issue yet, ideally you'd put them right where they came from for the exact wear. They are all the same length and spec, so just toss them each into a hole and you should be fine.


#3. I use a quality brake cleaner for all gasket surfaces. Accept no substitutes if you don't have the Rico cleaners...but a couple cans of brake cleaner.


#4 Agreed..you need to smooth the sharp edges or it'll cause KR. Just hit it like Rico said and don't hit the valve.

#5 I never put anthing on new OEM TTY bolts either. They have red stuff on them.

#6 You are this far...may as well do as Rico says.

I'm sorry I forgot to mention this VERY IMPORTANT note about reusing the pistons.

Whatever you do with the pistons, if you're installing new rings, make absolutely sure there is no carbon in the ring lands. New rings and carbon do not get along. The carbon will decrease the amount of compression distance for the ring when they get up to temperature. If the ring has nowhere to go when it expands it'll wreak havoc on the cylinder walls and possibly break the rings or snap the lands. Just another common mistake of the novice.

An easy way to clean the lands (chemicals won't help here):
Take an old ring and snap it in half
Use the broken ring to scrape the carbon from the lands
Make sure you can see nice clean aluminum at the bottom of each land
Try not to remove any aluminum from the land surfaces that are perpendicular to piston travel
If the ring has to much play in the land it will twist back and forth on every cycle and eventually snap

Let me know if you're installing new rings and I'll explain how to check another very important thing: ring gap

Hope this helps

1. I didn't suggest not torquing, I only addressed the copper because it wasn't said how thick or thin to apply. Add what I said to what Rico said.

2. Really.. we have super simple engines. I'd think if you had run into different lengths in the past, you'd have paid attention to it on disassembly.

3. I only use brake cleaner. Wearever in the black and gold can is my favorite. Doesn't mean it's the best or not the best. Merely adding another suggestion so you dind't have to search for it.

4. Whatever you got..smooth it out.

5. Cool.. it's all the same .. there's something on them, done.

6. Then why would you take off the heads? I wouldn't have.

7. That's a good question for Chuck.

I understand.. but with some searching you probably wouldn't have spent the extra $70 on HG's.

Since you had the oil leak, you are changing the rear engine cover gasket...right?

#7
Piston clearance should be 0.005" + 0.002" or - 0.001".
In my opinion you'll never see a 3800 at -0.001" unless you're spec'ing an engine that has just been bored.

Easy way to tell if there's a problem:
Turn crank to move piston to bottom
See if you can catch a fingernail in the ridge that is just below the deck, concentric to the cylinder
If theres a lot of slop in the piston more than likely there will be a ridge
If the ridge grabs your fingernail and holds on then the cylinder is most like OOR and out of spec
To get an accurate measurement go get a set of feeler gauges and slide them between the piston and wall

If one or two of the cylinders are slightly OOR you should be OK if not changing the rings. The engine may run quite a long time like this. Especially the 3800 SII.

For a racing engine this would most definitely need to be addressed. I use a hand honer (220 grit) and a bore gauge. If the hand honer puts the piston clearance out of spec then a trip to the machine shop ensues. Over sized pistons are expensive.

If I'm doing a 3800 block that needs rod resizing, align hone and the cylinders bored I put the block in the back of my truck and align the nose of my truck with the nearest scrap yard. The expense of all this work is just not worth it. There are a ton of these engines out there that do not require all of this machine shop work.

Well..if you took the heads off to replace gaskets, they you should consider doing the nearly always leaks gasket at the same time. Just tossing that out there, because not doing that gasket would be like reusing your leaking valve cover gaskets.

Great info guys Ive been wanting to rebuild my engine for a while now I have a good idea of where to start and what I should look for. Let us know how you engine turns out gtp89.