So i just put together a minime for my civic (d15b7 block/ d16y8 head). It smokes like a train. Greyish blue thick smoke, so i assumed it was burning oil. Did a wet and dry compression test.

Dry results were: 140, 140, 155, and 160psi. Wet results were: 190, 185, 195, and 200psi.

Obviously the rings are bad because of the change in psi between dry and wet tests, but they are all above 135psi which is wat the "Haynes" manual says is the minimum allowed compression. Is it still safe to say that the amount of smoke is still only caused by the rings? I'd hate to replace them and figure out it didnt fix the prob.

 

bump

 

maybe cylinder walls? If it ran rich, then maybe walls are scored which will kill rings and the wall.

could also be valves seals.

 

You may try the valve guides/\ as he said above that is a Notorious honda flaw if its an older engine then 9 times out of ten the valve guides are shot and need to be replaced

 

Yea i had also thought the same about the guides. I dont know the history of the block, nor did i know the person i bought it from. He just told me that the bottom end was fine, and the motor blew a head gasket and he thought the head was messed up too?? The y8 head that im using came off of my buddies motor that spun a bearing about 3 years ago. Back then when it ran, there were no smoking issues, but the motor also sat in a garage for 3 years..

 

Also the smoke that im getting is constant while im driving, not just at high rpm or anything like that ( i can see the trail of smoke behind me in the mirror). And when i first start the car, there is no smoke from the exhaust for the first 10-15 seconds at idle

 

It's your rings sir. Not your valve guides. -Later, BR

 

^x2

My D15B7 had 175-180 compression across the board...Haynes may say that 145 is the minimum, but it's pretty clear that your rings are shot.

fm

 

I dont know much about your situation, but when my b-series was smoking it was wornout valveseals.

 

Normally its either the rings, or valve seals.

Replace the rings, and while its apart replace the valve seals.

 

valve seals or rings is usually the case. ive rarely seen the techs at honda ever replace any guides

 

Iwent ahead and replaced the rings. First test drive it still smoked (def not as bad as before), but completely cleared up after about 5-10 miles. Guessin it just took a lil bit of time for the rings to seat completely

 

its normal for the car to smoke for a few miles after a rebuild. just check your oil occasionally to make sure its not burning anymore oil and change ur oil about 500 miles after the rings are broken in and you should be good to go

 

^ okay. thanks for the info!