Damn damn damn! After months looking all over the place for the continuing running problems with the RX motor I think i have to bite the bullet and pull the heads. Got around to doing a compression test and low (ie 70-80psi) in one cylinder. No reason to suspect gasket as no water or oil problems or smoke, same goes for rings - so my guess is a burned or slicking valve that wont close. Will need a special allen socket thingy to get the heads off (high tensile bolts with socketed heads) and will get to see what head work has been done on the old girl. At least it explains why i'm not getting the power i should and why the AC always stalls it. Wish me luck!

Give us an update after you get them off.

Rob

Yes - will do. Curious to see these mythical forged pistons. Thats if I will be able to tell the difference. What do standard turbo pistons look like from the top?

 

Fixing this should also improve the low manifold vacuum problem, which sometimes caused the odd brake 'fail' where the pedal goes hard; and plays havock with the interior ventilation system - accelerate and air goes to feet, back-off to get air in face - wheeeee!

Turbo pistons are flat for low compression.

Rob

Did the RX come with Forged Pistons?

i think the forged pistons thing is a myth. they're all cast.

Andrew, I think from reading his post, Red's engine is a bit modified, thus explaining the head bolts and the pistons.

Sorry Rob the EA82T pistons in my 87 are not flat, as seen below

Here is another look at the top of the engine block

http://www.westol.com/neper/EA82Tpistons2.JPG

 

 

Red, your comments on vacuum are no doubt from an valve staying open, possibly from carbon deposits? Some Seafoam in the PCV valve may clean the carbon off. "MotorVac" a walnut blasting technique is also ment to remove carbon as are some other methods. Easier than yankin a head??

Exhaust valves can burn also though, a cylinder leak down test will tell.

 

On the dash vent wierdness, and power brake. Sounds like you have some check valve issues. There should be a check valve in the white cannister on the shelf behind the dr. side strut tower and one in the line to the power booster.

Hope the pictures help.

This engine came from a rally car and has had a number of rebuilds - apparantly including forgies. From wot i saw in the cam boxes we have 30-70/70-30 cams (from thick billet) and high-tensile socketted head bolts. No-doubt the ports have been altered too. Will be interesting to see.

Thanx Skip - u just beat me to it. I tried a can of the Subaru upper cylinder foam stuff - no joy. I DO have a check valve in the brake booster hose - no idea of the state of the white cans guts tho.

Well - after pulling the manifold - and dissolving all that carbon and muck on the inlet valves, i got an even 100psi all round (cooold engine - no manifold or plugs). So i am going to risk it and put it back together with my fingers crossed.

RedRX

 

 

How many miles on that engine?

 

I have a EA82 with 100K miles, it runs almost like new.

viceversa - not sure since last rebuild. When i got it had huge injectors and fuel pipes, so i guess it was running waaaay rich, which i guess could cause the grunge. I'm hoping it was just grunge.

Originally posted by baccaruda

i think the forged pistons thing is a myth. they're all cast.

 

amen. that story goes back years on this message board...ive never seen a stock EA82T with forged pistons.

 

RedRX, how radical are the cams? any HP numbers? i had a head gasket problem in my turbo XT (vortex to you) and wasnt showing any tell tale signs (i.e. water/oil mixture or smoke), just a very tiny track mark on the under side of the head where coolant leaked into the combustion chamber.

30-70/70-30 cam timings - no idea of lift (i didn't put them there). From what i can see thru the plug holes and by hand turning the engine the pistons seem to look like they should (black and a tiny bit crusty - ie no steam cleaning). No HP figures cos not running just now and only really been running on 3 cyl before.