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84 Subaru Headgasket

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So I just picked up Subafly's old 84 4x4 Wagon. He said it he was driving it one day and it just lost power. So I got it started and oddly enough it ran freakin perfect and made power and all for about 5 minutes. Shut it off and tried to start it up again and it ran like crap and didn't want to idle. I checked out the oil and sure enough the oil was nice and milky.Anyway possible that block sealer would do the trick? Somebody said that it could be intake manifold gaskets as well?

 

That and can I go with felpro headgaskets? Need to have the heads checked? I've heard crazy stories about people driving these things up to 10,000 Miles on a BHG. The car has got 240k on it.

 

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Edited by Resortx

A lot of the people us Fel-Pro because it doesnt require a re-torque.

 

GD just posted a head re-surfacing technique. But yes, you need to have them checked and resurfaced if you cant do it yourself.

 

And as for going 10k on BHG... Yup. NED is doing just fine at over 7K on BHG. I just keep the coolant topped up and the oil topped up (I leak a little bit externally on start-up and burn it off while driving)

If you have coolant and oil mixing like that - you have a bad HG or a popped out freeze plug. Intake manifold gasket wouldn't do it.

 

Block sealers will not help you - the oil will prevent them from cureing. You have no recourse but to change the HG's and check the freeze plugs in the heads.

 

If you drive it like that it will destroy the bottom end in just a few hundred miles. Coolant and oil mixed together don't lubricate for beans.

 

GD

HG jobs really are not that bad if you can follow directions step by step. I was able to do it in 2 days (not counting machine shop time) and only needed to refer to the how to for torque patterns and #s, and timing procedure. Take lots of pics as you tear it down for reference.

 

Driving on blown HGs is asking for catastrophic failure. Aluminum warps pretty easily, I saw enough soccer mom Legacies and Foresters driven to death to vouch for that one wholeheartedly.

 

As far as block sealer is concerned, I really want to falcon punch the lady that owned the car before me. I wasted a good hour flushing that crap out of the block and radiator. It's like putting "Slime" in your tires. It serves it's function for the immediate future, but makes future maintenance absolute hell.

 

After a gasket set, fluids, machine shop work, and various other tidbits; I had under $300 into the project.

  • Author

Alright Haha yeah I know how BHG's go I've had a few MKIII Supra's and those are a BHG Mess. Haha Subaru's are ridiculously tough from what I have seen compared to most cars. Ill be pulling the heads though for sure and have a shop check them out. I have another engine out of my other one that I will probably yank out and drop into this one though. Probably do the rear main on that block too.

i had an XT6 that was driven a few thousand miles with a leaking headgasket. when i pulled the engine apart the area between the coolant passage and combustion chamber was warn down, pitted, and strangely rough (not smooth like a rock warn by water). i suppose localized overheating or something else was happening at the leak point to do that.

 

if oil/water is mixing then you're definitely hosed. i would never run a block like that or want to keep the engine if it was - like GD said bearings have tight tolerances and will fail if compromised.

 

it's going to depend how and where the breach is but the general notion of running long term with bad HG's is probably not a good idea. external leaks would be low on the worry list though.

  • Author

Haha Alright Ill probably end up resurfacing the heads and calling it good... Pulling the engine hopefully before snow falls and doing the rear main as well as headgaskets and than its going in my old wagon.

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