mudrat79 Posted October 2, 2004 Share Posted October 2, 2004 A stumper Question For all you REAL mechanics out here in USMB land...... I'll give a Buck to the first one to give me the correct diagnosis on this Problem........ This is Pertaining to Brad's ( Subaru Styles ) RX Wagon..... This car Ran poorly on the first Motor which Blew up really good with barely 75 miles on it.....We Installed another Motor, and It still ran As poorly if not worse.... After Many different tests, we Finally came down to a Compression test and here are those Results...... # 1 .) had aprox 50lbs # 3 . ) had 125 lbs # 2 . ) had 30 lbs # 4 .) had 145 lbs This was on initail Turning over.....we Retested and Both 3-4 came back with no compression, and 1-2 had around 125-135......????? thought maybe bad Tester......???? It's new, But we got another from a bud Who Owns a Proffesional grade one, with the same results...... We hand Turned the crank several revolutions, and tested again.....We Got good Compression out of whichever hole we tested for 1-2 revolutions of the cylinder....on retesting, it would be gone......????? We have already determined the problem, and Are fixing it ......I am curious as to where or what you all would do to figure out and Diagnose the problem....???? Feel free to ask Me questions here....... Look Forward to the results..... John Quote Link to comment Share on other sites More sharing options...
Vanislru Posted October 2, 2004 Share Posted October 2, 2004 Sloppy T- belt ? Quote Link to comment Share on other sites More sharing options...
mudrat79 Posted October 2, 2004 Author Share Posted October 2, 2004 Nope.....Keep trying..... Big Hint.....!!! Think About why Each Hole might have Good Compression For 1-2 Revolutions, then Have Compression go to nothing.......???? Then After it Sits.....Or is Hand Cranked several Revolutions, it Comes Back for 1-2 revolutions again.....????? Quote Link to comment Share on other sites More sharing options...
WoodsWagon Posted October 2, 2004 Share Posted October 2, 2004 Mybe the lifters are filling slowly and not opening the intake valve, leading to no charge in the cylinder, hence no compression? Quote Link to comment Share on other sites More sharing options...
mudrat79 Posted October 2, 2004 Author Share Posted October 2, 2004 Not the Problem......Valve staying closed would Allow for compression, but no fire.........How would you trouble shoot this Issue though....? Keep trying...... Quote Link to comment Share on other sites More sharing options...
oddcomp Posted October 2, 2004 Share Posted October 2, 2004 valves sticking open Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted October 2, 2004 Share Posted October 2, 2004 maybe the lifters are sticking and keeping the valves open to have very little comperssion then sits, the lifters slowly go down and giving you compression until they fill back up......? Quote Link to comment Share on other sites More sharing options...
MilesFox Posted October 2, 2004 Share Posted October 2, 2004 i would figure it has a dropped valve seat, that may be loose enough to let the valve seal on and off, but if you look at the head with the cam case off, it will appear the valve is stuck open. Quote Link to comment Share on other sites More sharing options...
Mykeys Toy Posted October 2, 2004 Share Posted October 2, 2004 I am certainly no mech. but I second the sticky valve. Quote Link to comment Share on other sites More sharing options...
JWX Posted October 2, 2004 Share Posted October 2, 2004 its either vavles or rings with a leaky head gasket putting oil into the cylinders edit or a broken crank Quote Link to comment Share on other sites More sharing options...
subaru_styles Posted October 2, 2004 Share Posted October 2, 2004 maybe a post will give a hint.. Quote Link to comment Share on other sites More sharing options...
oddcomp Posted October 2, 2004 Share Posted October 2, 2004 cams not phased correctly i think ken had a problem with that also Quote Link to comment Share on other sites More sharing options...
TheSubaruJunkie Posted October 2, 2004 Share Posted October 2, 2004 Yup, sounds like those cams were screwin up alittle. Is that what caused your other EA82T to go? -Brian Quote Link to comment Share on other sites More sharing options...
Scoobywagon Posted October 2, 2004 Share Posted October 2, 2004 Well, I don't think its a sticky lifter. I don't think you develop enough oil pressure to fill the lifters when you are just cranking by hand. However, given the intermittent nature of the problem, it almost definitely will have something to do with valves. Now, having never seen the innards of an EA82, I have to say I'm making some big SWAGs, here. How would I troubleshoot it? I think I'd first pull the cam covers and watch the valves while hand cranking just to have a visual check that they either are or are not working properly. If the valves are going up and down as they are supposed to, then we need to make sure that they are traveling the full distance that they are supposed to and are therefore fully opening and closing. If you are getting proper lift and duration, then cams need to be re-timed. If the valves are moving up and down, but aren't achieving proper lift and duration, then I'd think you'd want to replace the cams and lifters. If the valves aren't moving like they are supposed to, then I'd check lifters and timing belts. Quote Link to comment Share on other sites More sharing options...
subyrally Posted October 2, 2004 Share Posted October 2, 2004 oil pressure Quote Link to comment Share on other sites More sharing options...
Danbob99 Posted October 2, 2004 Share Posted October 2, 2004 What if the piston rings weren't seated correctly? could they hold pressure long enough to test, but under pressure move to allow a loss of compresion? i'd pour oil down each hole and re-test too see weather or not piston rings where the problem. I'd also be trying to find out where the air thats leaking out is going...i'd put my hand over the oil filler to see if exaust air is coming out there, or listen weather air is coming back up through the intake (can you hear that? i've never tried?) to see the valves move you can pull the exaust off and watch through the exaust port. Now, i've heard rumor that there is a funny vent tube on the carbed blocks that isn't adaptable with the turbo's...i don't really know the details on that one though... Quote Link to comment Share on other sites More sharing options...
rallyruss Posted October 2, 2004 Share Posted October 2, 2004 hmm all the valve checks are all well and good to check. I assume this is with the motor installed in the car? I would dorp the exhaust and retry just incase it was pluged. I once had a no start after an engine replacement of an overheated motor. turns out the exhaust pluged up real good. another thing I would want to know it what a vacume gauge showed while cranking. Quote Link to comment Share on other sites More sharing options...
GLCraig Posted October 2, 2004 Share Posted October 2, 2004 Well at sometime Subaru had to upgrade the valve springs, on EA82s, because of a lifter pump-up problem, I've been told by a couple of 25+ year Subaru Techs that this will sometimes happen when doing a compression tes. This maybe the problem. Quote Link to comment Share on other sites More sharing options...
subawoohoo Posted October 2, 2004 Share Posted October 2, 2004 ok i guess that when it was cranked by hand, someone spun the engine backwards. i just dont see how you could have sticky valves, first on the 1 and 2 then on the 3 and 4. so im guessing the "tester" had a little too much . am i close?? Tyler J. Quote Link to comment Share on other sites More sharing options...
subawoohoo Posted October 2, 2004 Share Posted October 2, 2004 perhaps your timing belts were off a hole bunch of degrees. hurm, thats quite a thinker. it sounds like the timing wasnt right, so if your valves and piston wernt "n'sync" i would guess timing. was this a problem on the original engine as well? Quote Link to comment Share on other sites More sharing options...
bajavwnsoobnut Posted October 2, 2004 Share Posted October 2, 2004 Was just talking to Subaru_styles the other day and I and guessing the cams where defanately out of phase or could they have been installed on the wrong sides? What could happen, ya never know cause they could be designed to run on a designated side. Or were they screwups form the company than made them then? Oh yeah the suggestion that styles is saying in this thread in his post is Read his Sig . Considering he has Delta CAMS and all!!! Quote Link to comment Share on other sites More sharing options...
subawoohoo Posted October 2, 2004 Share Posted October 2, 2004 well that was my first guess, but i thought that cams couldnt be switched. Quote Link to comment Share on other sites More sharing options...
ruparts Posted October 3, 2004 Share Posted October 3, 2004 maybe a shop towel left in the intake or air passage tube and forgot to remove ??? A stumper Question For all you REAL mechanics out here in USMB land...... I'll give a Buck to the first one to give me the correct diagnosis on this Problem........ This is Pertaining to Brad's ( Subaru Styles ) RX Wagon..... This car Ran poorly on the first Motor which Blew up really good with barely 75 miles on it.....We Installed another Motor, and It still ran As poorly if not worse.... After Many different tests, we Finally came down to a Compression test and here are those Results...... # 1 .) had aprox 50lbs # 3 . ) had 125 lbs # 2 . ) had 30 lbs # 4 .) had 145 lbs This was on initail Turning over.....we Retested and Both 3-4 came back with no compression, and 1-2 had around 125-135......????? thought maybe bad Tester......???? It's new, But we got another from a bud Who Owns a Proffesional grade one, with the same results...... We hand Turned the crank several revolutions, and tested again.....We Got good Compression out of whichever hole we tested for 1-2 revolutions of the cylinder....on retesting, it would be gone......????? We have already determined the problem, and Are fixing it ......I am curious as to where or what you all would do to figure out and Diagnose the problem....???? Feel free to ask Me questions here....... Look Forward to the results..... John Quote Link to comment Share on other sites More sharing options...
Danbob99 Posted October 3, 2004 Share Posted October 3, 2004 i thnk the valve timing idea isn't the one, i just cannot fathom in what fashion that the t-belts would be off to allow for that sort of compresion test result. So what i gather from the test results is that the left side tests good, right side bad. Test again and right side tests good, left side bad. I don't get it...makes me wanna get to the engine my self and start trying to figure it out. (up for company in oregon? ) I'm going to assume that it's a true hardware issues, something is weird with the parts being used. you say it was the same with the old engine that got blown up; was it also a carbed block? So being the second complete rebuild with the same re-ocuring problem...i'd assume it to be with something that you are using. The cams, the block, the heads. Huge crack in the head? naw...sticking lifters? possible...but the problem is to consisten, i sticking lifter you would think would be an in-consisten problem. I'm probably going to be thinking about this untill the wee hours of the morning...i'll get back to you when i figure it out. Quote Link to comment Share on other sites More sharing options...
Zefy Posted October 3, 2004 Share Posted October 3, 2004 hmmmmm... a mystery... sounds like a job for ME!!! hahaha... this is coming from the same guy who can't figure out how to get an axel off... bloody piece of poo... Could it be spoiled pistons??? maybe something of the wrong size??? its problably going to be something really crazy... like there was a penny under the seat... or the dome lamp was left on... or maybe... just maybe... you have a flat tire??? ok ya i'm done... Quote Link to comment Share on other sites More sharing options...
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