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EA82T compression problem(before pic of head added)


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Finally got the bugs worked out of the ignition system in the RX.

I was only getting one pulse from the crank angle sensor to the computer,

instead of four.

Checked all, and I mean all the wiring, and found the

open circuit in the harness before it goes into the firewall.

Car will start and run if you keep the revs up, will not idle.

 

Hell, it’s pretty impressive for a 2 ½ cylinder car.

 

Now a new problem has arisen that is taking all the fun out of this rebuild.

Compression check wet and dry gives me cylinder #3 at 50lb. and cylinder #1 at 25lbs.

 

 

 

Car was timed correctly. I did a leak down test on

both the cylinders with the cam case removed and timing belt off passengers’ side,

exhaust manifolds off and the throttle plate open.

 

When I charged the cylinders with compressed air (150lb) it resulted in the piston turning to its lowest position,

no leaks from int or exh.,

and a very slow hiss from the oil passages leading to the pan.

Both cylinders leak past the rings slowly at about 5lbs in 15 seconds.

I don’t think this is excessive enough to cause the low compression by bad rings.

Test was done on a cold engine.

 

engine_bay_and_front_end_069.jpg

 

 

 

 

cam_boxes_and_heads_086.jpg

 

I had the heads gone through, three angle valve job, new seals, and pressure checked before they were installed.

engine_bay_and_front_end_015.jpg

 

Pulled the head and the headgasket does not show any signs of leaking, Looks like it did when I put it on the car (47 lbs.).

 

Heads off the car and fill the intake passages up with fluid, no leaks. Same results with the exhaust side.

 

Mounted the cam case with the cam(Delta) and checked open/close and the valve seats, it’s all good.

 

The lash adjusters are suspect. When I pulled them while rebuilding they spent most of the time sitting on the bench upright.

They got knocked over a few times.

Soaked them for a while and attempted to pump them up submerged in oil,

but they would not compress.

 

Could bad lash adjusters cause the low compression by holding the valves open?

 

 

 

I’ve got 10 days to find this problem and fix it and I am at a loss.

Carlisle is coming up and a stock 2002 Legacy is not my ride of choice.

 

 

 

. I've got pictures of everything I did when I put this engine back together.

I've looked for the Wiley Coyote sign that says something was wrong and I'm not seeing it.

You want to see something to get an idea of wear and tear or what I've done, let me know.

 

 

 

Looking for educated guesses

 

Thanks,

 

 

Jay

 

 

 

 

BTW, If you have taken the time to read this post,

reply with your suggestions. what can it hurt and

you might lead me to the culprit. thanks again, J

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so you did a comp test and it came up bad? and then you tore apart the engine back apart to try to fix it, correct? I'd guess the numbers you said wouldn't hurt the comp test that bad. so I would say you had something with the lifters. and are you sure the timing belt were timed right? I messed them up on my GL-10 when I put it back together so that another possibility.

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What color paint is on the valve springs? Early EA82s would sometimes develope a lifter pump-up problem that would prevent the valves from fully closing. They switched to a heavier spring that was painted green one end. The early springs were painted red.

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did the die come out of the intake or exhaust? if not I don't think its the lifters, coz they would hold the valves and the die would come out of the intake/exhaust, right (I know you asked for educated guesses and these are not educated guesses)

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Jay this sound exactly the problem I had on my ea81t. & a lifter did fall on the floor on the weak cyl....I put money on lash adjusters....drive car in 2nd gear at very high rpm's for a 1/2 mile or so, to pump lifters back up. If engine is apart, try manually pumping lifters back up in oil bath. If that doesn't work replace adjusters on that side. The jy lifter I got was already pumped up, but from sitting it wouldn't budge. I let the jy lifter bleed down over night before starting car.

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to my knowledge, a comp test on a cold engine is useless. they always scare you when you do it, cept when its hot, then you know for sure.

the hydros would collapse if they were bad, so, that shouldnt have anything to do with your problem.

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Haven't checked the springs to see which one they are. Will do tonight.

I have another set of lash adjusters that only have 21K on them,

so they are going in once I get the head pressure checked again.

 

Did the compression check on a hot(wet)and cold(dry) engine.

Same #'s both times. A bit lower on the cold test.

 

Did the leak down test on cold only.

Thought it would be worse.

 

Unfortunately, before I started this rebuild,

I didn't check compression and ASSumed because

the engine was running

so well that everything as far as rings was up to snuff.

Now I definately wish I would have done it. At least to take it out of the equation now.

 

cam_boxes_and_heads_055.jpg

rings on # 3? But blowby wouldn't explain #1. See how pretty!

 

 

Jay

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Ran the car for about two hours total, longest time was 45 minutes. Gave it a 'I don't care, Blow it up' run too.

 

Machine shop looked at the heads today and they check out OK. Need to check valve spring tomorrow.

 

May send the cam back to Delta to verify OK. Going to reassemble with new lash adjusters and factory cam to see how it does.

 

If it doesn't run correctly, I'm going to rebuild the bottom end of the other turbo motor I have and start from there.

 

At this rate, I probably won't make Carlisle with it. damn.

 

Jay

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Ive had a few of the turbo engines run like crap, until ther were run for a few hours and driven a little gently...and taken on a few all out runs...then they usually purr and behaive properly.

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its hard to help diagnose a motor that is torn down and not in front of me(or any one else)

If I understand correctly I would give you three things. most have been covered already.

first- the cam timing off has to be the most obvious. make sure you have it correct. I have messed it up more than once.

second- the lifter issue. but you would have heard a lot of lifter noise if that was the case.

third- blown head head gasket. improper torque method? over torqued?

if you are running delta cams you will have lower compression readings as well. just keep that in mind.

what was wrong with the motor originaly? I may have missed that part.

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My dead lifter episode had no noise associated w/ it. The lifter simply would not hold pressure any longer. Subaru mechanics stand by their lifters, when I tell that story; they say impossible. They say did you run the engine at high rpm's for at least a mile to pump it back-up. No I didn't, well there ya go, it's not dead. OK...whatever! All I know is when I put different lifter in, I got even compression. Jay....manually pump those lifters before you put them in.

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