My new 347

[4pointslow]

Oil leak

I thought there was NO oil going through the cylinder head on the 302's.
No drain, No pressurized oil.
Someone correct me if I am wrong.

One of the last pictures I thought looked a little shinny coming down from the valve cover.

 

[4pointslow]

found this

http://www.badasscars.com/index.cfm...ct_id=119/category_id=13/mode=prod/prd119.htm

 

[delexploder]

Good find and good point! What kind of valve cover gaskets are you using? And are you sure the bolts aren't too long , that's been a problem before

 

[Dono]

I know this:
1. the leak is not coming from the valve cover gaskets
2. I'm certain beyond a reasonable doubt that the leak is not lower intake related.
3. I do know that I had all surfaces perfectly clean and dry before the head gaskets went on - I used brake clean and a lint free cloth on the block, and heads.
4. The head gaskets came out of the package and straight to the block surface, they touched nothing. I handled the head gaskets only at the very edges with clean hands.

The question now is, do I attempt the head gasket swap in the truck? The problem with this is cleanliness, and the brake booster. Some of the head studs would have to be screwed out, and stay in the head for head removal.

I think the only reliable way of inspecting the issue and performing removal/replacement is to have the motor on a stand.

It could be something foreign was on that spot of the gasket causing the issue, but I was very clean about the install. It could be there is an issue with the oil return hole in the head being offset a bit too much.....I'm not sure. This will have to be part of the inspection as the head comes off. Lots of could be's. At least I know exactly what, and where I'm looking at/for.

I just want to get this right.

 

[CDW6212R]

There are drain back holes at both ends of each head, and they are big holes with no chance of gasket alignment issues.

If it's from the head gaskets, it would have to be from either a "scratch" in the gasket where the drain hole is, or something thick stopping the gasket from crushing fully.

Those are both super unlikely, I'd be very very sure that the oil isn't coming from the intake or VC seam, before pulling a head.

Clean the back end of that head again really well(I know, tight to get in there). I'd even put a dab of RTV along the head end seam, to stop any oil from sneaking along that seam. Make the oil drip or flow over the RTV or where you can identify it better. Run the truck enough to produce enough oil to reach the block etc, and then hunt upwards again to see where it came from. I'd do that again to be sure it's the head gasket before pulling the head.

 

[Dono]

I know you are right. Further diagnosis is the right thing to do.
This will happen.

Although, I'm certain the leak is not coming from the top of the china wall. That rules out the lower intake gasket.

If you look at one of the pictures after I cleaned all the sealing surfaces with the lower intake off, you can see china wall to head is sealed. When the head gasket was installed, I even used some rtv on both sides of the gasket at the china wall. This all comes back to the oil drainback hole at the head.

4pointslow, there are two drainback holes in each head. one at each end. Unfortunately, I am reasonably certain I will be able to take pictures of this with the head off. I'll take detailed shots.

On Saturday, I am getting help from one of Tims lifelong friends. He just happens to be way up there on the motor mechanics chain and Tim says he is one of the smartest guys with automotive anything he has ever met (Although he would never tell him that in person lol). He already spent a good hour with various lights and mirrors looking. He confirms it is not the valve cover gaskets and finds the leak extremely odd. Odd enough that he really wants to find the issue. Saturday he has a date with my truck to use engine oil dye and a light to illuminate the area.

I'm sure the issue is head gasket, but you are right Don...It's key to diagnose this properly rather than chucking a bunch of labour and parts at it.

 

[Dono]

Here's a couple of pics showing the oil drain back hole. It looks like there should be enough meat on the head, and probably block to stop gravity fed oil.
Oil, definitely runs close to the end of the head sealing surface though.

 

[4pointslow]

Oil Returns

Those are great pictures of the oil return holes.
You can see that an oil leak there is possible, seems to be right where your leak is too.

Maybe something fell there when the gasket or head was going down.
Once I did a set of head gaskets on a dodge van, front wheel drive. When done it ran great with no symptoms, until the next morning when I went to pull it out of the shop. White smoke, I was like what?
Pulled the head back off and found the smallest piece of glass in between the head gasket and head. I looked above where it was and saw the hood light bulb was cracked and some more loose glass was inside the bulb still. I removed the bulb so no more glass would fall, and got a new gasket and the head back on. All was fine.
What are the chances of that happening?

Maybe check the torque on that one head stud before pulling the head off?

 

[Dono]

Thing is, I probably went over all bolts 8 or 9 times over a 24 hour period., including lower intake after it was on.
I can't imagine bolt torque being light.

I can't even imagine anything getting on the block, head, or head gasket (although the head gasket is sticky). I worked crazily (ocd style) cleanly and the head gaskets came out of package directly to the block head surface, paying attention to the correct orientation.

All that being said, I obviously did something wrong.

 

[vroomzoomboom]

On Saturday, I am getting help from one of Tims lifelong friends. He just happens to be way up there on the motor mechanics chain and Tim says he is one of the smartest guys with automotive anything he has ever met (Although he would never tell him that in person lol).

yup. smart ass hell (for a chevy guy lol). he has more certifications then i have underwear. that and if anyone has seen my thread, with the truck up on a lift, thats the guy. that is also had his house.
and yea, i wouldnt tell him hes one of the smartest mechanics i know, i would call him a hack and smile doing it (you would have to hear some of the comments we both through at each other, and some of the things we do to each other lol.

 

[Dono]

Here is the response from fel-pro on their gasket recommendation:
The Ford small block has some unique sealing challenges. Due to the design of the engine, the intake acts like a wedge during torque-up and the upper head bolts lose some of their loading. The Ford-specified intake manifold torque procedure was changed to help counter this - follow Ford's latest specs on this procedure.

There are a couple of things you can do to help prevent leaks beyond the manifold torque procedure. While we always stress to install our gaskets clean & dry, in this case only, you could apply a very thin bead of RTV to the “ears” of the head gasket (the 2 areas of the head gasket that extend up towards the china walls). The head bolt loading gets light here as the intake manifold tries to "pull up" on the heads, but your head studs should help with that.

So, on to the head gaskets - a graphite gasket will be the most accommodating to poor roughness/flatness conditions. so it's likely the surface finish wasn't a problem for the gaskets you were running.

Has the block been decked? If so, and if you can confirm the surface finish is 60 Ra or smoother, we would recommend switching to MLS head gaskets - especially since you're boosted. 1133 SD-4 Performance MLS gaskets would suit the build nicely, but again, the surface finish of the heads and the block need to be 60 Ra or smoother to be compatible with MLS gaskets.

If the block is not smooth enough for MLS gaskets, you could consider 1011-1 (1962-1982 blocks) or 1011-2 (1983-1995 blocks). These performance gaskets are steel core composite with pre-flattened copper wire under the combustion armor (will not brinell aluminum heads) and use Printoseal sealing beads to increase sealing stress.

also,here is the 'torque sequence' they talk about.
http://performanceparts.ford.com/download/instructionsheets/fordinstshtm-9424-302351w.pdf

 

[Rick]

That's very good info.

I'm running Cometic MLS gaskets with my 13.5:1 big block, but the heads and block were milled especially for them.

 

[Dono]

So, Im home drinking beer. Is plural of beer, Beers?

With the dye in the oil and up on the hoist, all corners of each head are leaking oil.
Keep in mind, there is no coolant leaking and combustion chamber gasses are not blowing in to the cooling system. So, what we have here is gravity fed oil leaking out the head gaskets on each corner. How can that be? Back to the beers comment.

It has to be those head gaskets. Makes no sense. Beer is my friend. Or is that beers?

 

[CDW6212R]

Well that does make no sense for head gaskets. I'd ask if that was after running the engine, but it doesn't matter, leaking from several areas is not good.

What head gaskets were those again, and that may not matter since the oil leak has been there before? Can you find out what surface finish the block and heads have, and ask Woody for his thoughts when he knows all of those details?

Go back to the beers, find something else to do on a Sunday.

 

[delexploder]

I'm betting there is an issue with the locating dowels

 

[shucker1]

Been watching this thread with interest.

A few questions but I may be off base, so forgive me.

If I recall you were using O Ring Style Head Gaskets?

If O Ring style gaskets require an wire cut in the face of the head then could it be that the undercut of the head is slightly too shallow?

This might prevent the corners of the head from pulling down tight enough to seal the oil return passages.

 

[Dono]

No o-ringed heads or block. There is a fire ring around each combustion chamber with the gaskets used, but no special machining required.

The locating dowels were cheap ones, as that's all I could find locally. I will have the non- cut style for the next round.

Anything is possible, but unless the heads are aligned wrong, I just don't see it. I'll work slowly at the pull. I'm shooting to get the diff out today, but I'm not counting on it. Spring yard work has begun. That and I'm not moving very quickly after last nights beer(s?).

I'll leave the oil with the dye in the motor, and ill be able to prime the crap out of it and look for exterior leaks.

 

[shucker1]

Sir,

There is no problem with beer.

It actually lowers cholesterol and has all of your needed basic grains.

Perhaps next time a feeler gauge set under the corners of the heads during each step of torquing to see if the corners are trying to lift?

 

[Dono]

Slipping a feeler gauge under there is a great idea! maybe I'll even try slipping a feeler in that area (ok, is it me, of does some things just sound horribly wrong?) before taking the top of the motor apart.

I'm not too worried about my cholesterol or arteries, but I'm going to get concerned for my liver if I cant finally get this motor right soon.

Ed Curtis has been very patient with me as well, here is his response. It doesn't sound like he truly believes that its the head oil returns leaking.

"There is always an issue with the tri-corners on some installations. I usually dab a little bit of the Permatex Ultra-gold at the top of the head gaskets before bolting up the heads. This is a low torque section of the head as the intake bolts try to lift the edges as you tighten them up. Then a tall bead of RTV at the China wall before bolting up the intake. On highly modified heads and intakes, I also put a light, thin film of RTV on the intake ends so that when they meet the wall of RTV on the block there is a bond taking place. You must let this all set for a day before adding oil."

I think I did exactly what he suggested on the last head install, except I only went down the china wall/headgasket about 1/2 to 3/4 inch with rtv.

Rather than use the cheap locator dowels, these are the one piece units I'll use this time
http://www.flowtechinduction.com/fti-sbf-head-dowels/

 

[delexploder]

Any updates?