Oil leak from between head and block

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swedefish

swedefish

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I´ve got a minor oil leak on the engine and haven´t been able to locate where it comes from, today I took a couple of pics of the area it´s leaking from.
This is what I found......:cheers:
....not!!!!
Any one got an easy fix for this?
The block has been square decked and the heads were supposed to been milled to straight surface. I´m using a steelshim head gasket, would an added copper gasket fix this leak?
 
You sure it's leaking from the head/block and not up above, but, that's the area that it finds it's way out?

Could be the rear intake seal, especially the corner where the head/block/intake merge.
 
Use a mirror, and maybe pull the carb.. It looks to me like it's more likely the intake gasket. I've never had to use spray copper on them before and it looks like there's a trail leading down from the intake flange..
 
Thanks guys.
cracked: I had a look at the rear intake seal, right after your post, but it´s all dry around that area.
When I pull the head I´ll first inspect the intake seal, to see if it hasn´t sealed properly. Is there any obvious signs to look for on the intake seal, besides the oil of course?
Thanks again for your inputs, very much appreciated.
Lenny
Btw, should the iron 915 heads be retorqued after a warmup, when recently installed?
 
swedefish said:
Thanks guys.
cracked: I had a look at the rear intake seal, right after your post, but it´s all dry around that area.
When I pull the head I´ll first inspect the intake seal, to see if it hasn´t sealed properly. Is there any obvious signs to look for on the intake seal, besides the oil of course?
Thanks again for your inputs, very much appreciated.
Lenny
Btw, should the iron 915 heads be retorqued after a warmup, when recently installed?
Click to expand...
I am going to say yes to retorque...and what kind of intake gaskets are you using..I run ultra black silicone front and back and along the bottom edges of the intake gasket where it meets the lifter valley before I put the valley pan on..I have heard to spray those steel shim gaskets with copper spray...M2C
 
bremereric said:
I am going to say yes to retorque...and what kind of intake gaskets are you using..I run ultra black silicone front and back and along the bottom edges of the intake gasket where it meets the lifter valley before I put the valley pan on..I have heard to spray those steel shim gaskets with copper spray...M2C
Click to expand...

Thanks BE
I´m using this intake gasket http://www.summitracing.com/parts/FEL-MS96007/
a Fel-Pro gasket from our local speedshop. Only using the rtv sealent where the block meets the heads. This is the first time I did not use the rtv sealer on every area on the intake gasket.
A stupid question, should I allow the copper spray to dry for some time before mounting the heads?
When I come to think about it, it seems that the leakage got worse when I switched oil from 20-50 oil to Royal Purple 10-40 oil
 
Had a couple of photos with the cellphone from the area between the valley pan and intake.
By the looks of it I do got an issue with the sealing of the valley pan.
 
swedefish said:
Had a couple of photos with the cellphone from the area between the valley pan and intake.
By the looks of it I do got an issue with the sealing of the valley pan.
Click to expand...
Looks like you got it....synthetic oil will leak better than non-synthetic oil...take you intake and valley pan off....wipe everything down with MEK and use permatex ultra black...
 
Yesterday I retorqued the intake bolts, were able to torque another 1/4 of a turn. Started the engine and had it running for a couple of minutes while inspecting the area where it´s leaking from with a mirror, but to no avail. It still leaks
Tonight I pulled the head.
While unbolting it I figured that I would test to have the bolts retorqued to 70 ft/p. With the head bolts under the valve cover I was able to turn the wrench a half of a 1/4 of a turn.
Testing, I would say they were torqued to ~67 ft/p. How much of a difference would this make?
I´m going to clean the head and gasket tomorrow and check for the straightness of the head.
 
swedefish said:
Yesterday I retorqued the intake bolts, were able to torque another 1/4 of a turn. Started the engine and had it running for a couple of minutes while inspecting the area where it´s leaking from with a mirror, but to no avail. It still leaks
Tonight I pulled the head.
While unbolting it I figured that I would test to have the bolts retorqued to 70 ft/p. With the head bolts under the valve cover I was able to turn the wrench a half of a 1/4 of a turn.
Testing, I would say they were torqued to ~67 ft/p. How much of a difference would this make?
I´m going to clean the head and gasket tomorrow and check for the straightness of the head.
Click to expand...
I thought you were sure it was coming from the valley pan and the intake mainifold?
 
ALL steel shim head gaskets REQUIRE a retorque after engine break in. ALL of them. they also require some form of coating such as copper kote. Some people used to use spray paint because the lead content actyally bonded to the gasket with heat. Paint doesn't work anymore because of no lead. I would try retorquing the heads first.
 
bremereric said:
I thought you were sure it was coming from the valley pan and the intake mainifold?
Click to expand...

When looking a little closer I couldn´t find any oil at the rear intake seal that was finding its way further down at the back of the cylinder head, all dry there.
I wasn´t sure but hope never dies, after I had the intake retorqued it was still leaking. When starting the engine up and let it warm up a bit while inspecting the area with the mirror I saw a drop of oil coming from the lower corner of the head (marked in the pic below).
My thought was that while I was having the engine apart this far I might as well pull the head and have it checked.
Probably had multiple issues, both the intake and the head, although the oil from the intake stayed on the valleypan.
One thing that sucks is that the header needs to be removed to be able to retorque the heads.
 
swedefish said:
When looking a little closer I couldn´t find any oil at the rear intake seal that was finding its way further down at the back of the cylinder head, all dry there.
I wasn´t sure but hope never dies, after I had the intake retorqued it was still leaking. When starting the engine up and let it warm up a bit while inspecting the area with the mirror I saw a drop of oil coming from the lower corner of the head (marked in the pic below).
My thought was that while I was having the engine apart this far I might as well pull the head and have it checked.
Probably had multiple issues, both the intake and the head, although the oil from the intake stayed on the valleypan.
One thing that sucks is that the header needs to be removed to be able to retorque the heads.
Click to expand...
yep...WAB...if you remove the heads I would get some new steel shim gaskets and spray them down with the copper coat...let them dry and put them on and torque em down..
 
Thanks guys
Question: About the retorque of the other head, when trying to retorque the head, the lower headbolt(underneath the exhaust port) did not move at 70 ft/p.
Should I just leave it at that and do the next bolt in the sequence?
 
Ohh, how easy this would have been with the engine in the test stand,:banghead:
 
swedefish said:
Thanks guys
Question: About the retorque of the other head, when trying to retorque the head, the lower headbolt(underneath the exhaust port) did not move at 70 ft/p.
Should I just leave it at that and do the next bolt in the sequence?
Click to expand...

yes.

Isn't it aluminum in general that you always check/re torque...

Type of lube used on the fasteners will effect the torque as well...

It's a good idea to run a tap down all the head bolt holes before the next head install.
 
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