Nuts, bolts, washers, gaskets - what must be replaced with engine apart?

[LeeH]

I'm working my way toward the heads, which compressions tests suggest have bent valves. Hopefully the pistons and cylinders won't need to come apart.

The engine only had 5000 miles when I over-revved it. Which nuts, bolts, washers, and gaskets need to be replaced and which can be reused?

I need to place an order today and want to try to include as much stuff as I can.

[SoCal70RSR]

Lee,

For replacing as many nuts/bolts/washers etc as you're going to replace, you're better off looking for a local place that sells hardware in bulk. There's one about 15 minutes from my house and every time I go, I think I have enough, I've been there 3 times and I'll probably go one more time so I have enough to replace all/most of the hardware once the engine gets put back together. Good luck.

[randywebb]

doesn't Wyane have a kit with everything needed?

[LeeH]

Originally posted by randywebb
doesn't Wyane have a kit with everything needed?

Yes, but with about 55K total on the engine and 5K on a top end I'm trying to just buy what I need.

[Early_S_Man]

Lee,

It sounds to me like all you need to replace after only 5K miles ... would be the 'normal' Nyloc M6 and M8 nuts and aluminum sealing washers for the sump, chain, and valve covers. I normally order those by multiples of 100 ...

[Gunter]

Warren said it.
New Nyloc nuts and washers come with the gaskets for the valve covers and I think that kit also has the stuff for the sump.
I have in the past just re-used the gaskets and nuts/washers without problems (Leaks)

Make sure you apply the correct torque to the head studs with a calibrated torque wrench when you finish up and do it according to Wayne's book.
The 3.0 has Alu crush seals on top of the cylinders in a groove.
It's up to you if you want new ones; I re-used the old ones (Just don't disturb them, leave them in the groove)

With bent valves, check the rockers and adjusting screws for damage.

[tech 1]

Lee, You might as well face it......You'll need to buy another top end gasket set.Head gaskets should never be reused,nor the nylocs or crush washers.Remember what I told you before.....be shure to ck that valve to piston clearence.DO NOT use the new head gaskets when assembling the engine for this test.You may find that you have to eyebrow the pistons a little more.I have the exhaust valves touch the pistons on a stock 3.0 with nothing more than just the addition of 964 cams.Let me know if you need help with this I don't mind walking you through it.Tim.

[Gunter]

Originally posted by tech 1
Lee, You might as well face it......You'll need to buy another top end gasket set.Head gaskets should never be reused,nor the nylocs or crush washers.Remember what I told you before.....be shure to ck that valve to piston clearence.DO NOT use the new head gaskets when assembling the engine for this test.You may find that you have to eyebrow the pistons a little more.I have the exhaust valves touch the pistons on a stock 3.0 with nothing more than just the addition of 964 cams.Let me know if you need help with this I don't mind walking you through it.Tim.

Tim, I agree, that would be the safe way.
I have re-used undisturbed head gaskets on 3.0 in the past without problems but the safe way would be new ones. My reasoning was that the 3.2 doesn't have any head gaskets and I didn't disturb the seal in the groove. To my mind, it is more important to do the torquing of the head studs correctly to ensure the heads sit square on the cylinders.
I assume that he will follow correct procedure with this partial rebuild and check the deck height and cam timing.
Re the higher lift of 964-cams on your stock 3.0:
What type? 930/07 or 930/16?
What CR?
CIS-piston-domes?
What overlap did you adjust for the cam timing?
I have 98mm P/C's for CIS, 9.8:1 CR, 964 cams and I set the overlap at 1.4mm without any issues re deck height.

[Walt Fricke]

I don't know the modifications of your moter like others seem to know.

But leaving those aside I'd reuse all my gaskets (other than the head/cylinder seals) and all my hardware, as long as the parts looked OK. I replace the crush washers when they get so crushed they are hard to remove. I have had no instance of a used nyloc coming loose.

The big rubber O rings for the cam holder ought to be fine. Check the delta shaped 3 bolt gasket for the holder carefully, though. A downside to using some gasket cement on this one is that it can tear apart on removal. Replacing just this one with the engine in the car can be done, but it is a whole lot of work. The chain case cover gaskets are kind of delicate, but a guy ought to be able to get several cover removals out of one before he tears it.

Might this leave a slightly wetter motor? I suppose so (especially when the valve cover gaskets are getting a bit long in the tooth, though I have taken to liking Hylomar to lengthen their useful life). In a shop you can't do this kind of thing. Cheaper for the customer to put in new gaskets and new hardware rather than cleaning, inspecting, dressing, etc. At home you can. A little wettness I can live with - mine are going to get damp via a few of the rocker shafts anyway. If this bugs you later on, it isn't a big deal to put on some new valve cover gaskets.

The only time I haven't replaced the cylinder top groove gaskets was when I discovered I had made a major installation error - engine stands can let you lose track of which way is up. No problem resulted but they had seen no heat at all. These are somewhat expensive puppies, so I have wondered about just reusing them, but if there is a problem it might not just be a bothersome oil leak a guy could easily enough fix. I also note that after the gasketless 3.2s Porsche revered to gasketing this joint, did it not?

Walt Fricke

[Gunter]

Good stuff, Walt.
Yes, During '91 Porsche added head gaskets on the 3.6 because some leakage was experienced by some owners of '89-'91 - 964s.
Strangely, the Carrera 3.2, without head gaskets, didn't have problems.
And the over-sized 98mm P/C's have no head gasket.
Go figure.
I still think that the most important issue is that the mating surfaces between cylinder are clean, not warped and that the correct torque is applied.
Meaning: Moly on the studs and washers, gently snug the barrel nuts crosswise, then pre-torque crosswise, then final torque.
Re-torque after ~1k mileage.
I also re-use nuts, bolts and washers.
Re: Gaskets. For valve covers and chain covers, I smear Moly (Anti-seize) on both sides and have re-used these gaskets for a long time.
I found that the gaskets don't stick to the metal with lube, are easily removed, and don't get damaged. Again, I believe that as long as the surfaces are clean and not warped, there should be no leak.
That's going back to many years of experience in industrial applications.
The delta-gasket on the cam seal is somewhat delicate and has to be positioned carefully. Some use sealant, some don't.
Hoping for no, or just tiny, leaks.

[LeeH]

Thanks for the guidance. I ordered quite a few gaskets. The chain housing cover gaskets and valve cover gaskets all fell apart. I ordered the kits with new gaskets and hardward. Figured I might as well replace some of the hard to get to things like oil cooler gaskets while I was in there.

I don't plan on lifting the cylinders so I planned on leaving the cylinder to case gaskets in place. The flywheel seal and half shaft cover are leaking badly, so they're on my list also. I did order new flywheel bolts.

Do I need to check the deck height as part of this partial rebuild? It doesn't seem like anything will change that could affect it.

Any advice on removing old gasket material? The upper valve covers mating surface look like they haven't been properly cleaned in a long time.

[Gunter]

Yeah, take a dinner knife and make (Grind) it into a little scraper.
Carefully scrape away the remaining old gasket-material.
Try my method of putting Moly grease on both sides of the gaskets when installing; they won't stick after that.
Deck height should be good; re-check the torque on the studs.
Final torque is normally 24 ft-lbs but, for checking after some mileage, I use only about 22-23 ft-lbs.
Out of curiosity, you migh want to check the cam timing if you like.
Quote: "The flywheel seal and half shaft cover are leaking badly"
With only 5k on the engine, the main seal shouldn't leak; maybe a bad install? New seal goes in with a little oil on the lip.
What do you mean by: "Half shaft cover"?
Half shafts are the axles with the CV joints.
Do you mean: Intermediate shaft?

When you are finished, make sure you rotate the engine by hand with plugs removed to ensure that all is well meaning: The pistons won't hit the valves.

[MBEngineering]

The engine only had 5000 miles when I over-revved it.

HI Lee I think you should be pulling the cylinders off and the pistons to replace the rod bolts, as the rod bolts do NOT like being OVER REVVED, you tend to put the engine back to gether and it then decides to open it's self up on it's own, big time!!! I have some photos of what your engine will look like if you do not fit the rod bolts , but for some reason thay will not load up.

regards mike

[Gunter]

Wow! That would mean splitting the case; virtually a complete rebuild.
Lee: Post some pictures of the bent valves so we can see how severe the over-rev was.
If the pistons just "kissed" the valves, the rod bolts may be o.k. but Mike raises an issue.

[MBEngineering]

|HI Gunter you can replace the bolts without splitting the case, you just need to grow a 3rd arm and thin hand, or get a trusting friend/mate to help, and not drop the bottom of the rod cap in the cases, a good magnet comes in handy hear.

regards mike

[LeeH]

Originally posted by Gunter
What do you mean by: "Half shaft cover"?

I meant intermediate - not half.

I don't think the valves are severely bent... but that's just based on looking at the exhaust valves with a flashlight. The two cylinders that had compression offer some resistance when turning the engine by hand. I can also hear air being sucked into the intake valves on those two. Not the other four.

Gunter: you say I "might want to check the cam timing." I thought this would be mandatory after this level of disassembly. Is there a way to remove the heads without having to start over with the cam timing?

[MBEngineering]

HI Lee I think Gunter is asking you to check the cam timing before you strip off the heads , as in your last posting you where looking down the ports and turning the engine over I assume the engine still has the heads/cams on, it would be good to check if the chain has jumped or it was just valve bounce??. you will have to set the cam timing when you put the engine back to gether, it will be good practice to check it now.

regards mike

[Gunter]

Lee:
Mike said it.
What type is your engine? 930/07? 930/16?
Look down the right side of the right fan post; it's stamped on the case, not the post. Ignore the long cast number on the post,
It is important to know because different years have different overlap.
Valve covers are off, remove the plugs, slack off all valves completely, check/set the valve clearance on #1 & #4 intake, set the pulley to TDC (Z1) compression stroke (The rotor in the distributor points to the notch) mount the dial indicator on the collar of the #1 intake valve, then check the overlap according to the books (Wayne's Engine Rebuild and/or Bentley)
Do you have these books?
If not, you'll need them.
Read up on the procedure, then practise on both cams.
Take pictures!
To remove the heads, the cam towers have to come off meaning: Remove the tensioners, remove the chain sprockets, etc.
Keep track of the position, and number, of the shims under the sprockets.
The books tell you about the correct procedure.
Read up, it's more involved than you might think.
Any mistakes here with the shims, gaskets and O-rings will mean misalignment of the chains and/or leaks.
Take pictures ; they'll help you for re-assembly later.
Is this engine stock? Any mods? Stock cams?

[LeeH]

I'm out of town right now... will check the case when I get back tomorrow. Yes, it's still together. I ordered the camshaft tool which should arrive in a few days.

I've got the books and have read and reread the sections on setting the timing. Figured it would make more sense when I'm actually doing it. I like the idea of checking it before disassembly.

The engine is stock except for 20/21 grind Web cams. I need to get the Z block and dial gauge. I see Wayne sells the Z block, but not the gauge. Any suggestions for a source?

[Gunter]

The dial gauge needed for this has to have a special long extension; a standard gauge with short extension will not work.
Try finding a used one on the Pelican board; long extension is the key.
Prefer metric but it'll work with inches if you do the conversion.
1mm is 0.040".
Since you have 20/21 cams, ask Camgrinder John what timing he recommends giving him the engine #.
Do you have CIS or carbs?