OK, hopefully some of you guys with more engine experience than me will help me out here. I just swapped to Edelbrock performer heads. I used the Felpro 1094 to get everything where we needed it. Jakeshoe helped me wit the math (cause I couldn't figure it out :(). On the right side of the engine I have an oil leak at the back of the head. I've added engine dye and the only place I have any sign of the leak (this time) is just under the head on the block, not behind the manifold at all, like I said this time, I did have a leak I just fixed there.

I installed the gaskets dry as advised by some other guys that ran them. What are my options at this point? Replace the gasket and use some sort of copper coat or similar product? If so should I do both sides? Can I just pack the edge with silicone? Set this piece of shit on fire and call it a day?

Any advise, or ideas would be appreciated.

Knuckle, I sprayed those gaskets with copper spray before I installed them on my 355. I never had any leaks.. I do remember the instructions said the head and block surface should be pretty smooth ,Like 60 rhs or some kind of smoothness rating.. If you keep leakin in the same place you might have a problem with either the head or block surface in that area.. Thy to clean it real good then make it leak again to pinpoint the spot..
Good luck
Hulk

Heck, before I'd burn her to the ground, I'd clean the leaky spot(s) up good using BrakeKlean and let it dry and then daub on some good old messy Permatex, "Indianhead Shellac Gasket Cement" and let it dry b/c I figure the old crap will seal her right up!!

And I know it will seal a cracked intake casting fine!!!!

Been there, done that....

pdq67

I too would do my best to seal it up, but would use silicone. (I'm a modern kinda guy in regards to sealants lol) Any seepage you deal with there is not under any pressure (unless you have a blowby issue) and should seal up rather easily. In addition to brake clean, I would use compressed air to blow all the oil out.

You have experienced one of the reasons we will not use shim head gaskets, hopefully you won't have to pull the head to fix it. Good luck!!:)

Rust,
He's using the Fel-Pro rubber coated gaskets. Damage must have occurred to the gasket during handling or assembly for it to leak there unless there is a defect in the block or heads at that spot.
I second what rust says, CLEAN, CLEAN, CLEAN, silicone, 24 hrs drying time.

I can't imagine that it's coming from the head gasket. There are no oil ports between the head and the block where a head gasket failure would cause an oil leak.

Is there any kind of misfire going on? If you had a blown head gasket, it would likely cause problems like that.

Open your radiator cap and see if there is any oil in there.

You shouldn't have to go to a shim gasket to make this work (and I don't even think they'll work with Aluminum heads anyway).

Do you have a oil fitting on the back the block behind the intake? Did you mess with it during the head swap? Maybe you dislodged it??

Pull the rocker cover off, clean out all the oil on the rear of the head and see if you can see any kind of crack or porosity in the casting. Maybe there's a pin hole or something that's passing oil?

I can't imagine that it's coming from the head gasket. There are no oil ports between the head and the block where a head gasket failure would cause an oil leak.

Is there any kind of misfire going on? If you had a blown head gasket, it would likely cause problems like that.

Open your radiator cap and see if there is any oil in there.

You shouldn't have to go to a shim gasket to make this work (and I don't even think they'll work with Aluminum heads anyway).

Do you have a oil fitting on the back the block behind the intake? Did you mess with it during the head swap? Maybe you dislodged it??

Pull the rocker cover off, clean out all the oil on the rear of the head and see if you can see any kind of crack or porosity in the casting. Maybe there's a pin hole or something that's passing oil?

Mike, with the dye it's obvious it is leaking at the back of the head, no doubt at all. I've cleaned and ran it 3 times to make damn sure. I certainly do not like the idea of pulling the head.

If you look at most places that leak, how many of them are under pressure. The main leaks I can think of are manifold, distributor gasket and valve covers. All major leak areas but no pressure. The main oil drain is at the back of the head. I think Jakeshoe may have nailed it in a PM, the gasket possibly got bent at corner (top back as you look at the head)

The math can't lie. I need the shim gasket to get the quench where we wanted it. It changes the compression about a half a point. Felpro said it's good to go with aluminum heads. A number of guys here have run them with no issues.

I'm going to clean the crap out of it and pack it with sealer and see what happens. I'll know in time to pull the head this weekend if it doesn't work.

I can't imagine that it's coming from the head gasket. There are no oil ports between the head and the block where a head gasket failure would cause an oil leak.


You shouldn't have to go to a shim gasket to make this work (and I don't even think they'll work with Aluminum heads anyway).



There is a "leg" portion on each end of the head gasket that extrends up the block to the point where the deck surface transitions to the intake rails. If this leg was damaged it will definitely leak oil there. Same deal as the end rails of the intake not getting sealed.

A shim gasket will work with an aluminum head, particularly this coated gasket from Fel-Pro, and yes it was necessary to maintain compression and quench in this case.

There is a "leg" portion on each end of the head gasket that extrends up the block to the point where the deck surface transitions to the intake rails. If this leg was damaged it will definitely leak oil there. Same deal as the end rails of the intake not getting sealed.


Got it.

I've never used a shim gasket so I guess I was talking out of my a$$. But how thick is this gasket? I assume that the GM .028 gasket wouldn't have cut it in this case?

Any rate, since this area isn't under pressure, hopefully the tried and true "smear silicone on it" method will do the trick.

Good luck!!!

Got it.

I've never used a shim gasket so I guess I was talking out of my a$$. But how thick is this gasket? I assume that the GM .028 gasket wouldn't have cut it in this case?

Any rate, since this area isn't under pressure, hopefully the tried and true "smear silicone on it" method will do the trick.

I've got my fingers crossed.;)

I've got my fingers crossed.;)

Better than your wires!! :crazy:

Myself I don't think I have every seen a head gasket leak oil.

What about the little port at top rear driver's side of block, thats half covered by the head? The one where if you miss installing the plug during build you have to pull the head off to put the plug in afterwards.

Myself I don't think I have every seen a head gasket leak oil.

What about the little port at top rear driver's side of block, thats half covered by the head? The one where if you miss installing the plug during build you have to pull the head off to put the plug in afterwards.

I think Dave said it was coming down the passenger side of the engine.

It is an unusual place for an oil leak, but I think Dave did an in car head swap and the potential for damaging a head gasket during install is much easier this way.
I've done my share of installing iron BBC's while leaning over a fender. Surely Dave could set the alum SBC head on with one hand :)

It is an unusual place for an oil leak, but I think Dave did an in car head swap and the potential for damaging a head gasket during install is much easier this way.
I've done my share of installing iron BBC's while leaning over a fender. Surely Dave could set the alum SBC head on with one hand :)

I think I tried it that way. I remember one went on a bit "rough" and I believe it was this side.

I just swapped heads and had no leak before, so that naturally eliminates a lot of stuff.

Knuckle,

You've got a frustrating problem there!
I've seen it happen and it seems like everyone here has the same opinion regarding the possiblility that you may have damaged the gasket during installation.

Besides the requisite cleaning of the block deck and head surfaces, I would usggest you coat the block deck with aluminum paint immediately before installing the shim type head gasket.
You could use copper coat or Hylomar too but Aluminum paint has more particles in it than coppercoat and will take-up the gaps and uneven surfaces better.

I'm not a real big fan of Silicone but if you did decide to goop it on the leaky area, I'd suggest the Permatex 26 Ultra Copper.

We've used this technique on many aviation enignes with great success.

Dont forget the possibility of the oil running down between the block and head from the intake gasket. Leaking around intake area, and gravity pulling it down along the block/head along the head gasket.. and then out the back.

Dont forget the possibility of the oil running down between the block and head from the intake gasket. Leaking around intake area, and gravity pulling it down along the block/head along the head gasket.. and then out the back.


This is exactly what happened to me and it looked just like the oil was coming from the head.

Dont forget the possibility of the oil running down between the block and head from the intake gasket. Leaking around intake area, and gravity pulling it down along the block/head along the head gasket.. and then out the back.


Yeah I just re-sealed the intake and it slowed the leak down. I've got oil dye in it and the black light shows the fresh oil as bright green. It appears it's leaking about where Jake suggested I may have bent the gasket runner. No sign at all along the bead at the back of the manifold, sender is clean so is the distributor. The top of the block is dry, just the right side at the shelf where the trans bolts up. I have a slight leak at the left VC, but that's a easy fix. We'll try the silly-cone and see what happens. I'm getting pretty good at taking it all apart if I need to go that route. I just feel the pressure to make it to the meet on the 11th :)

I just feel the pressure to make it to the meet on the 11th :)

The thought of sitting at the "special" table giving you some angst, Dave? :crazy:

Knuckle,



Besides the requisite cleaning of the block deck and head surfaces, I would usggest you coat the block deck with aluminum paint immediately before installing the shim type head gasket.

I'm not a real big fan of Silicone but if you did decide to goop it on the leaky area, I'd suggest the Permatex 26 Ultra Copper.




The Fel-Pro gasket mentioned is not bare steel, it does not need any type of sealant to install, nor would I suggest using any.

I believe that gasket is just .015 comp. thickness..
hulk

jake, I may be wrong but I gathered that the block was not decked since the removal of the previous heads. That being the case, I was suggesting something that I was taught from a machinist to help prevent a possible problem.

The aluminum paint acts as a filler and a sealer.
I have used rubber coated and plain metal gaskets in automotive and aviation engines with this technique for many years with no incidents of problems or leakage.

I often use silver spray paint or copper-coat on steel shim head gaskets. Nothing wrong with the technique, it just isn't necessary on these gaskets. I am certified as a Master Engine Machinist, although I no longer do it on a daily basis, but in the case I would defer to the manufacturer of the gasket. No sealant is necessary.
When I do use paint, I don't use it on the deck or head surfaces, I spray it directly on the gasket. I prefer not to paint the cylinder walls, pistons, etc... and don't want to spend the time to tape all that off when I can paint the gasket while holding it and then immediately set it on the deck.

Well jake,

We have some things in common. Namely, I am also a certified master machinist as well as a member of SAE and SEMA. I have been a tech specialist for many of the aftermarket companies and also consult frequently.

As you well know, there are many things that can and have been done outside of the normal manufacturers instructions with great success for people that have "less than ideal" situations.

I do agree with the problem of time and effort to mask off the cylinders but if we can prevent the problem of the gasket not being applied to the full surface and eliminating the possibilty of damaging the gasket again, I believe it would be worth the effort. Also, I neglected to state that the gasket should be coated on both sides as well. By doing this on the block and gasket, it helps to increase the "tack" between the materials and help create a stronger bond. Also, the small amount of paint on the piston heads would not be a problem as it would be burnt off anyway.

We may not agree here and that's okay.
It was merely a suggestion of a procedure that has been used with success and I was sharing it as an option to help out a member with a frustrating problem.

I have found your advice and experience on these boards very helpful and insightful to the members. I hope together we can continue to help people here with their questions and problems to help them enjoy their 2nd gens more on the road and not in the garage...

This is not a old engine, the block was decked 6000 miles ago. While that is still time to change some things I did some checks and felt comfortable using the gasket. I appreciate all the advise I have received. I have been a tech for just over 20 years, but I have minimal experience in engine and transmission repair. And almost none in high performance upgrades. I have found over the years almost no two mechanics do the same job the same way, and again I appreciate the different points of view, that's why this board works.

Last night I cleaned it again and applied the silicone. Not really the ideal situation but it will hopefully work. I just can't help thinking I rushed the job the first time and fubared the gasket in some way. Knowing it must be poor workmanship pisses me off to no end :(. I'll let you guys know if the patch worked.

I too am a certified shade tree mechainc with a degree in Farenheight, Centigrade and Kelvin.

I've used these gaskets on too many engines to count but I am limited to fingers and toes.

All kidding aside, I have used these gaskets and EVERY time I've used them we've painted them with aluminum paint, let it dry for a few minutes, then installed them on the dowles on the block, then installed the heads, then installed the head bolts using Permatex #2 on the threads of the bolts and a light coat of oil on the heads of the bolts. We (I) never had a head leak compression or coolan't. These engines ran the gambit from street to racing (drag racing and dirt track stock cars) too. The majority of them were un-decked blocks too.

IMHO, your leak is near or at the intake gasket. I know most of you modern boys like using RTV for the end gaskets whereas old dogs like me still use the rubber end gaskets with a light coat of either Permatex #2 or oil resistant RTV. And I might add, I've never had an intake gasket leak oil on the ends although I did have one Edelbrock intake that leaked oil up the center two bolts on the cylinder head side till I put Permatex #2 (what else) on the the threads.

Kamikaze,
Painting of shim gaskets is a sound technique, I just don't feel it is remotely necessary with a gasket that is already "coated" for the same reason you would paint it. The coating on the Fel-Pro gasket is there to fill in imperfections and create a seal once it gets hot.
I also don't know why you would paint the deck surface when you can paint both sides of the gasket, lay the gasket on the block, set the head on, etc all while the paint is still wet.
Paint on the top of a piston isn't an issue. On a carefully prepped cylinder wall, no thanks. I doubt it would hurt anything, especially with oiled cylinder walls, but with all the trouble we go through to maintain cleanliness on assembly, I try not to add anything unnecessarily.

NO luck for me this week. I still have the leak on the right side, and in a lessor degree a leak on the left. Both in the area of the leg Jake was talking about. I'm going to pull the heads tomorrow and with any luck stay on this until it's back together. I'm definitely not going to rush the job this time, nice and easy, but steady. We'll see if I find damage on the gaskets, if not we'll try some other sealing techniques.

Well I sure don't want to jinx myself here, but it looks as though the oil leak is fixed. As many of you have said it appears to have been the manifold. Once I got the plenum and the distributor off, I was able to get a better look. And the dye trail was fairly obvious. I sure appreciate the advise and encouragement. Special thanks to Jakeshoe for all the PM's he responded to and kept me on the right track. Dude, your going to have to teach somewhere, you certainly have the patience for it. :D

Man Dave,

Im glad you got it figured out. I kept my mouth shut because Ive had a mystery leak that has been saoking the right side header on my car. Now that the weather is getting nice I can track mine down. I really think I mangled the balance seal installing it or pinched the oil pan seal.

If it has anything to do with the head gasket youll be the first to know.:)

Take care,
Shane