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EA81 Cylinder Wall

Featured Replies

I pulled this EA81 down for a re-ring and it looks like one of the cylinders had a head gasket leak for a while. The machinist I work with recommends I find another block. What do you think, how much ring leakage will this cause? The pitting in the photo won't hone out. Should just save the internal parts and scrap this block?

 

[Click for larger photo]

th_Cyl_Wall.jpg

 

Thanks,

-Jeff

I just scrapped an EA81 block for the same reason..plus there were some other score marks towards the bottom

  • Author

That's what I was thinking. It's not worth the chance for all the work involved. I have a good crank/rods and cam core though at least.

that the one you got from me? i didnt think it was that bad it had blown head gasket symptoms for only maybe under 2 weeks befor i swapped it... it never got hot or anything just steamed:eek:

  • Author

Ya, that's the one. We took about .003 off the deck so it would hold a new gasket for more than a week, but the pitting in the one cylinder concerns me a little. The heads looked ok though. I'll probably either shop P-A-P for a better block or scrap the whole project and start looking for an EJ. That's probably what I should have done to start with:rolleyes:

 

BTW how much oil did it go through? Did it smoke a lot?

Edited by XT6 Magic

From the pic, the pits look like they are high enough that the rings at tdc would still be under them. If this is the case they probably wont hurt anything. Check it and see.

Doesn't look that bad to me. The second compression ring should be below that anyway. I would run it. These aren't swiss watches.

 

Run iron rings - chrome faced rings will take forever to seat in.

 

GD

you had to deck it? was the block warped.... because it never got over running temp while i owned it. it didnt burn to much oil it mostly leaked it. (it marked it's teritory) :lol: that engine ran like a champ every day untill i swapped it though... and it is amazing at 218,000 miles it still has the factory cross hatching

Edited by ()__1337_CRAYOLA__()>

+1 on running it... I would think the lower ring would be below that, it may burn a teeny tiny bit of oil, but a spot that small shouldnt affect your compression enough to worry about it.

 

LOL@ "These aren't Swiss watches"...

 

Are you building a spec or race engine? If so, I'd do something about it.. is this for your daily beater? I'd run it in a heartbeat.

 

When I built my first EA82T engine, it had been sitting with water in the#1 cyl for a year.. it didnt hone out, but I ran it anyway mostly cause I'm cheap and didnt have the money to do it right, and it had that kind of pitting 3/4 down one side of the cylinder... Passed emissions (I'm in CA) and ran like a champ... went thru about a quart of oil every 300 miles... smoked a little...

 

Tough little engines, I'd run it as it sits... That damage is so minor that unless you NEED to get the absolute most out of this engine, you'll never even know it's there.

 

88RxTuner

Edited by 88RxTuner

From the pic, the pits look like they are high enough that the rings at tdc would still be under them. If this is the case they probably wont hurt anything. Check it and see.

 

Have you measured it to see if this is the case?

 

If you add up all the "scratches" in the cross hatch, you'll probably have more area there than in those pits.

  • Author

Maybe I will try and run it then. It's just going to be a daily driver with a Delta Cam and DeMoss heads. I really don't have anything but gaskets and time to loose. I have a new set of STD pistons (the skirts on the old ones were collapsed about .003"). It's got to be better than what I am running now @ 1+ quart per 100 miles:eek:

 

The reason that we took .003" off of the desk was a small imperfection at the liner in one spot. It looks like it was the cause of the gasket failure but it cleaned right up.

 

What type of sealer should I use on the case? I have read 3 Bond, Ultra Grey 599, and Permatex Aviation (which flavor)?

 

Thanks,

-Jeff

I should think that because the case is not pressurized, any of those would work.. I tend to favor UltraGray Permatex myself, unless you could get your hands on some Honda Engine Case Sealer ( from the motorcycle shop...)

 

88RxTuner

  • Author

It would seem that the type of sealer used on the case halves could affect the main bearing clearance.

It would seem that the type of sealer used on the case halves could affect the main bearing clearance.

 

 

IIRC,I used Aviation Form a gasket #3 w/good results.You want a thin type sealant for closely machined surfaces.

IIRC,I used Aviation Form a gasket #3 w/good results.You want a thin type sealant for closely machined surfaces.

 

FLANGE sealant? ANAEROBIC sealant?

If you apply your sealant with some discretion, it comes up to perhaps .001" thickness.. I have found it really doesn't matter what you use, providing you apply it with DISCRETION and assemble your parts while the goo is still wet and "flowing".

The compression of the parts, in this case the engine halves, will indeed squeeze the vast majority of the sealant out of the joint. The sealant, in all actuality, simply fills the machine marks and bonds one side to the other for a liquid-proof seal.

If you inspect the engine case when you open it, or any other "goo-only" joint, I suspect you will find that the sealant has only filled what is necessary... I've found on every sealed part I've ever disassembled, the only accumulation of sealant is actually IN the machining marks of the part.. the majority of the surface contact is essentially metal to metal.

 

Hope this helps!!

 

88RxTuner

I use permatex ultra gray or you can get some honda bond (anaerobic) from a motor cycle shop.

 

Keep in mind that the subaru engine more related to a motorcycle engine then a car engine. With the split cases and all.

But any flange sealant, or anaerobic selant will be fine. As mentioned, use sparingly, it only takes a little bit. You'll see that those type of sealants come in a very small tube, for a reason.

I'd just buy a tube of threebong from Subaru

I'd find another block. It wouldn't be worth my time and money.

 

Just what I would do. YMMV

 

 

Doug

Three Bond, a little dab' ill do ya :lol:

Threebond is a brand, not a type, of sealant. There are many varieties of Threebond - just as there are many varieties of Permatex. Some of it is VERY different from the stuff availible in the states. I happen to have occasion to use actual Threebond products in my work.

 

For the case halves, use loctite 518. RTV is not reccomended.

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