mikeshoup Posted May 4, 2007 Share Posted May 4, 2007 According to Russ, this engine I got for free from him is low on compression on cylinder #1 and #4. What would cause that? How do check this? I guess I just need to start taking the engine apart and see what's going on. Also, the compression is low on all of the cylinders on my brother's car... 40,40,30,60... what would cause that? As you can see, I'm kind ignorant when it comes to engine problems. (Both of these are EA82s) Quote Link to comment Share on other sites More sharing options...
86BRATMAN Posted May 4, 2007 Share Posted May 4, 2007 Well, a number of things can contribute to low conpression numbers. Head gasket failure, bad rings, cracked or worn valve seats, bent valves(non realistic on an ea82), and the most common problem with the usual compression check is human error. Quote Link to comment Share on other sites More sharing options...
Nug Posted May 4, 2007 Share Posted May 4, 2007 If putting a couple of squirts of oil in the weak cylinders raises the compression, then it would be rings. If not, it could be valves/head gasket/something else. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 4, 2007 Author Share Posted May 4, 2007 Well, here's a question, how can I check the compression with the engine off the car? Quote Link to comment Share on other sites More sharing options...
DerFahrer Posted May 4, 2007 Share Posted May 4, 2007 Well, Mike's point is that it's unusual for two cylinders on two opposite banks to have low compression. I'd say cracked heads personally. Quote Link to comment Share on other sites More sharing options...
86BRATMAN Posted May 4, 2007 Share Posted May 4, 2007 Same way as you would in the car. Just use a ratchet and socket to turn the crank pulley. It may not give the same numbers. But usually you are looking for more consistancy across the whole engine instead of high numbers. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 4, 2007 Author Share Posted May 4, 2007 Well, Mike's point is that it's unusual for two cylinders on two opposite banks to have low compression. Yup, that's my confusion. Cracked heads, huh? Could be. I think the engine had a ton of miles. Quote Link to comment Share on other sites More sharing options...
jeffast Posted May 4, 2007 Share Posted May 4, 2007 Yup, that's my confusion. Cracked heads, huh? Could be. I think the engine had a ton of miles. 254,000miles, russ said, Quote Link to comment Share on other sites More sharing options...
Phizinza Posted May 4, 2007 Share Posted May 4, 2007 I have an EA81 here with 60,60,50,60 and it blows LOTS of blue smoky. So, if it's figures like that and no smoke, I doubt it'd be the rings. But that said, could be multiple things. To check valve seals and seats when the heads are off the motor poor kero in the valve ports nad watch for it leaking past the seat on the cylinder side. Then hold the head upsidedown blocking up the port and look for kero getting past the stem seal. You only need to hold it like this for 30 seconds or so to see how it fares. I'm pretty sure it's to hard to check rings, I guess just replace them and to a hone on the bores. And ofcause, you have headgaskets which are mostlikely the problem. Quote Link to comment Share on other sites More sharing options...
Nug Posted May 4, 2007 Share Posted May 4, 2007 YOu can perform an accurate leakdown test with the engine out of the car. Of course, you would need a leakdown tester. You can get them for $30 off of ebay. You'd need an air compressor, too. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 4, 2007 Author Share Posted May 4, 2007 YOu can perform an accurate leakdown test with the engine out of the car. Of course, you would need a leakdown tester. You can get them for $30 off of ebay. You'd need an air compressor, too. Neither of which I have I'm going to take the heads off of this motor and see if anything is obviously wrong. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 4, 2007 Author Share Posted May 4, 2007 I found the problem, at least for #4. The valve seat for the exhaust valve came loose and wedged itself between the valve and the port. The block is trashed though. The motor had to have been left outside and it got water in it through the spark plug holes that were empty... the cylinder liners are rusted and pitted. Didn't take the head off the other side... don't see a need to really. Could be a similar thing or something else. Don't really care now. This motor is trash. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted May 4, 2007 Share Posted May 4, 2007 Also, the compression is low on all of the cylinders on my brother's car... 40,40,30,60... what would cause that? With you're bros car. That sounds like either a totaly shot bottom end(rings) OR the timing belts are way off. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 4, 2007 Author Share Posted May 4, 2007 With you're bros car. That sounds like either a totaly shot bottom end(rings) OR the timing belts are way off. The timing belts were dead on. So its either the rings are gone, or my compression tester is off... I'm gonna check it on my car and make sure its not reading too low. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted May 4, 2007 Share Posted May 4, 2007 The timing belts were dead on. So its either the rings are gone, or my compression tester is off... I'm gonna check it on my car and make sure its not reading too low. Tear it down and re ring it. You don't even have to split the case. Ussually you'd want to and do new bearings too, but if you're lookin to go *el cheapo* just pull the heads and pistons, rering and go. Probably less than $100 bucks for rings and a HG set. You'll get a good couple years out of it at least. Which if it's rusty may be all you get anyway. Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted May 5, 2007 Share Posted May 5, 2007 motor had 256,000 on it. I did the compression test a few times to verify that the problem was compression and nothing else. After that, I removed the engine and never looked back at it. Sorry if its a bum engine Mike but I wasn't sure what was going to be wrong with it. Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted May 5, 2007 Author Share Posted May 5, 2007 motor had 256,000 on it. I did the compression test a few times to verify that the problem was compression and nothing else. After that, I removed the engine and never looked back at it. Sorry if its a bum engine Mike but I wasn't sure what was going to be wrong with it. No need to apologize. The only thing that bummed me was that it was left outside and got water in the cylinder bores... (I bet the other engine's heads are fine so all I really wanted was a decent shortblock) But yeah, I figured when you said the compression was low on #1 and #4 I knew something was bum. Quote Link to comment Share on other sites More sharing options...
Caboobaroo Posted May 5, 2007 Share Posted May 5, 2007 I was going to throw it in the dumpster but I didn't have the energy to do it quite yet so yeah, it sat outside since I pulled it:rolleyes: Quote Link to comment Share on other sites More sharing options...
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