Oil from head bolts getting into gasket at installation, a problem?

[JohnM]

Just finished installing heads on 96 OB. This is the second time I have noticed the oil from the head bolts seeping from the 

head gaskets after Subaru's torque sequence. I think it comes from the loosening of the bolts after torquing the first time.

Will this be a sign of failure if there is oil between the metal layers? I cleaned everything with lacquer thinner thoroughly and 

installed the gaskets with the head vertical on the engine stand. The previous attempt I installed head gaskets I saw the same thing and they failed. The engine is not in the car yet. 

 

John

 

 

[Fairtax4me]

You may be using too much oil. I've always just dipped the first 1/2" or so of the bolt into a small cup with oil. The oil will spread over the length of the threads as the bolt is threaded in.

 

I'm inclined to think that will affect the sealing of the gasket.

[idosubaru]

^ what he said up there.  too much oil and may compromise gasket sealing.

 

if you've only done the heads, i'd probably redo it with new gaskets myself just due to the shear time investment in this job. i'd rather know for certain it's once and done.  but time is very valuable to me. 

if you didn't resurface the heads then take them out and definitely redo it and resurface them while it's out.  they should always be resurfaced on these engines. 

if you've fully assembled it or installed then that's a conundrum. 

 

one fortunate prospect is that the fire ring is the issue on these and isn't it always the lower coolant passages below the cylinder on the lower portion of the head?

I think it is always the lower half - and only a portion of it - like 90 degrees, not the full 180. 

The only oil that would compromise that area would be the headbolts above the cylinder bore and physically speaking none of them are above the fire ring if gravity was the only component and everything was square to the ground..  Though with such compressed tolerances I'd imagine the oil doesn't take a directly vertical passage south...it probably spreads and migrates through the path of least resistance as the head/block/gasket come together.  So there's still chance of oil getting to that fire ring.  Maybe it would just smoke off, no big deal, and that doens't mean it can't cause issues elsewhere, i'm just focusing on the typical symptom of that gasket/engine.

 

You probably have a decent chance of being lucky but i'd rather know for sure for only 60 bucks and a little more effort.  Too each his own, you'll know how much time you got to deal with it now or later. 

[JohnM]

Too much oil on the threads is the issue, I believe, like you have stated. I haven't read anywhere how much to use. I see videos of guys just squiring it on

the threads and washer from an oil can. No warning about the oil working it's way back out of the hole as the bolt goes in and spreading into the gasket. So that's what I did, just squirt it on. The heads have been faced as well as the blocks. .020 over pistons and valve job. Yea it's a pain to disassemble the cams just to get to the head bolts. Since HGs are 90 bucks are they reusable if the engine has not been fired off yet? 

[idosubaru]

i've replaced the head gaskets once tightened even if it's never been fired up.  make your own move there.  

you can search, it's been asked before and probably tried before. though so few times that a search is going to be more fruitful than waiting for a reply probably. 

[JohnM]

Thanks, I found the tread started by Jellyman. Opinions are thumbs down to reuse. I think the car would be more fun using it as target practice. I'm sick of this HG crap.

 

I appreciate your responses. Helps guys like me make informed decisions. 

[Fairtax4me]

Once a head gasket is compressed its done. If you only made it halfway through the torque sequence you would be able to re-use it, but once the gasket is fully torqued it has to be replaced.

[idosubaru]

google search shows lots of people reusing MLS headgaskets after a torque but no run.  i wouldn't now but in college i would have probably given it a whirl.

[Gloyale]

Too much oil.

 

And not installed the right way.

 

I always install the head to the block, seated on the dowels with no bolts yet. Then I install the bolts using a tiny bit of oil on the threads and washer.  I hold the head down tight and run the bolts in quickly with an air ratchet (just to zero....no torque).  Also, during the loosen adn retoque I don't loosen a full 2, 180 degrees.....I just go to loose enough to have no torque....or less than the ~20 you will be starting the final torque with.  Keeping the head fairly tight to the block through the whole process keeps the oil in the holes.

 

I've never had an issue with oil seeping out....that sounds like too much.

 

I have resused Composite gaskets with 10k miles on them. Got them on my wheeler right now. Copper spray and a extra few ft/lbs...............

 

MLS......not so much.

Edited December 28, 2014 by Gloyale

[JohnM]

 Thanks for the reply G.

 

Too much oil I agree. I squirted it on and allowed it to drip off. The blocks were machined and thoroughly cleaned. The assembled block was on the stand with the cylinders in the vertical position - mating surfaces are horizontal. I thoroughly cleaned the block with lacquer thinner. The heads were also cleaned - no oil in or out of them. I removed the MLS gaskets from the  wrapper and placed them over the dowels. Then placed the heads over the dowels. Installed the bolts and torqued them to spec. Ya I thought the loosening 360 degrees was too much, but what do I know about Subaru gaskets?

The oil I feel just followed the path of least resistance in any direction as mentioned above. What did I miss besides the "used too much oil" part?

Edited January 3, 2015 by JohnM