Blew a headgasket - Looking for tips on cleanliness

voodoochylde · Post by **voodoochylde** » Wed May 23, 2007 1:35 am

Yes, blew the driver's side HG on my 1990 NA Legacy L AWD a while back and I've been busy polishing the valve covers and trying to get the heads clean.

Up to now, I've got the exterior pretty daggone clean (not that it matters) and the head mating surface itself is clean as well. I've used mostly water, dish detergent, and scotch-brite pads on the mating surface. Today, however, I found PermaTex Gasket Remover and bought a can of brake cleaner. Both worked very well to get rid of crud out of the combustion chambers and degrease the exterior of the heads.

My real question is how clean do the mating surfaces of the heads need to be? IOW, how much slack can the gaskets pick up?

I ask because I've got one darn near immaculate except for some discoloration at the edges of where the gasket used to be but the other one is proving much more difficult.

Once I'm satisfied with how clean it is, should I take some of my miracle stuff (Meguiar's Aluminum Polish) and put a mirror finish on the heads? I ask this because I've read that polished aluminum can get hotter than less-finished aluminum.

SemperGuard · Post by **SemperGuard** » Wed May 23, 2007 2:28 am

It doesn't need to be polished. It shouldn't be polished actually. Just make sure the old gasket is gone, and the surfaces are flat and shove it back together.

voodoochylde · Post by **voodoochylde** » Wed May 23, 2007 4:35 am

Cool, that's what I was thinking but wasn't sure one way or the other.

Thanks

isotopeman · Post by **isotopeman** » Thu May 24, 2007 2:35 am

Call me Mr. Anal, but I'd get the surfaces as clean as possible. Mineral spirits and scotch-brite pads work great to loosen all the residue and gasket material. Then wipe it with a little bit of mineral spirits on an old, but clean, cloth. Then wipe with a dry, clean cloth. The discoloration didn't seem to be something on the surface when I did mine, but the material itself.
Cleaning the outside is a good thing to do while you've got the parts out. You have to handle them to put them back on, and if they're greasy and grimy, you'll just spread that crap around where you don't want it.

voodoochylde · Post by **voodoochylde** » Thu May 24, 2007 6:32 am

isotopeman, we're of the same mind. Both heads are darn-near immaculate

Now I've another question...the gasket kits on ebay...how good/trustworthy are they?

The small gaskets I'm not so worried about - it's the head gaskets that concern me.

Example: Here

Also regarding head bolts - should I spring for the 160 dollar ARP Bolts from importperformanceparts or would the $50 ebay specials be fine?
Example Here

isotopeman · Post by **isotopeman** » Thu May 24, 2007 6:52 am

I'm not sure about the kits on ebay. I blew the passenger's side on mine and just got a head gasket from Napa for about 45$. In addition to that, I bought a new valve cover gasket set, even though I needed only one.
I used the same gaskets everywhere else after checking them over and cleaning them. (I even wash all my tools after every use.) I would love to have replaced everything; particularly the timing belt, cover and gasket, but $ was pretty short.
You can probably use the same head bolts. If you have a good set of calipers, you can check to make sure that all the bolts are the same length. (none are stretched or bent)
Most important is the sequence of re-tightening the head bolts. The instructions in the book seem odd, but makes sense once you're into it. I think there was a thread on this fairly recently that could be found again.
Are you by chance between NW Arkansas, St. Louis, and Memphis? I'll be making some more trips soon between these places and would be glad to swing by and help out.

voodoochylde · Post by **voodoochylde** » Thu May 24, 2007 2:52 pm

Thanks for the info, I'm not sure if I'll reuse my head bolts or not...I have no way to measure them and all I'd have to do is wait a week or so and I'll have the cash.

No, I'm nowehere near the places you listed. I live near Rainelle, WV in southern Greenbrier county. Thanks for the offer all the same - that's quite nice of you.

SemperGuard · Post by **SemperGuard** » Fri May 25, 2007 5:42 am

There's no reason to replace the head bolts unless they're broken. And I wouldn't trust my engine to a non-subaru gasket unless it was not offered by subaru anymore.

Splinter · Post by **Splinter** » Fri May 25, 2007 6:43 am

Im assuming you mean a non-subaru OEM level replacement gasket, not a cometic or something

wrxzzz · Post by **wrxzzz** » Sat Jun 09, 2007 6:37 am

pretty sure you have to replace the head bolts. They stretch when you torque them so they can only be torqued once. That's my understanding at least/

douglas vincent · Post by **douglas vincent** » Sat Jun 09, 2007 7:09 am

wrxzzz wrote:pretty sure you have to replace the head bolts. They stretch when you torque them so they can only be torqued once. That's my understanding at least/

Not to be rude, but thats a misconception....

I am running re-used head bolts on 30 psi blocks!

thehookeup · Post by **thehookeup** » Sat Jun 09, 2007 6:55 pm

douglas vincent wrote:
wrxzzz wrote:pretty sure you have to replace the head bolts. They stretch when you torque them so they can only be torqued once. That's my understanding at least/
Not to be rude, but thats a misconception....

I am running re-used head bolts on 30 psi blocks!

doug you are also a different breed of person, i still agree with you tho

legacycentral bbs

A forum for 89-94 BC-BF(BJ) Legacy Owners and Fans

Blew a headgasket - Looking for tips on cleanliness

Blew a headgasket - Looking for tips on cleanliness