Long background story short, my brothers 2003 civic si ep3 burnt two exhaust valves on his ep3. He only owned it for a few months, and then it started acting like a misfire on cylinder 2, but turned out to be those exhaust valves. So my uncle, father, and I decided to rebuild it. And yes, I know we couldve swapped a type r in for prolly cheaper, or a better K than the K20a3. Wasn't my car, I was just rebuilding. So a very reputable machine shop around my way rebuilt the head. And we did the bottom end with just new rings, bearings, and honed the cylinders. We kept getting a vtec system malfunction code cel come up. We replaced the vtec assy. with a known good one, and every so often, we still kept getting the code. Then we noticed it was using oil. And then it became apparent we were using a lot of oil.

Well just five minutes ago, my dad and I did a compression check on each cylinder and all of them came to 180 psi. And cyl 1-3 had a 5-10 psi increase when adding oil for a wet test. cylinder 4 had about 20 psi increase.

So any clue at all why its burning so much? We are talking a quart of oil every 100-200 miles.

We also noticed oil all around the number one cylinder spark plug threads and a bit at the bottom of the plug tube (right above the threads). And all plugs were burnt white at the tips.

Thanks guys!

 

What was your piston to wall clearance at after you honed it?

Did you check to make sure the cylinders were round after honing?

What were your piston ring end gaps?

What kind of break in procedure did you use?

 

Good questions.

Also do you see it burning oil like mad out the exhaust? When they rebuilt the head did they put in new valve stem seals?

 

It has been a few months since the rebuild, so I dont have the measurements off the top of my head, but we were within spec. And break in was what the machine shop owner referred us to do. Acceleration to red line and normal driving for about 30 minutes, then change engine oil.

and no. thats what is getting me. you see no oil at all coming out the back. and yes, they resealed the head.

 

Based on what you are saying, my opinion is that the oil rings didn't seat properly. Most of the time this is due to: Improper ring installation, loose clearances, improper honing procedures, and improper break-in process.

You could try to tear it down, re-hone and re-ring but chances are you'll need to bore it .020" over to get your clearances within OEM specifications.

 

Correct me if I am wrong, but being that the dry then wet compression tests didnt show a large variance in PSI, wouldnt that show correct sealing.

Could also do a leakdown to get the true story.

Also, after finishing it all, when we got it all back together and fired it up, it definitely smoked, from the bit of oil i dropped into each cylinder for the wet test. I would think, I would see the same type of smoking if the rings werent seating and oil was burning, like it did for the test and fire up. Maybe not as much, but still see something.

 

did you guys staggered the rings and did u go to larger rings? with honing the cylinders sometimes you got to go to larger rings for increase wall clearance. cylinder 4 doesnt sound good if it has 20 more than the rest during a wet test.

 

meaning did we line the rings up? no. they were all lined up in different positions.

 

After you honed the block and machine work did you properly clean it? and have you checked your coolant and oil to make sure your head-gasket is ok? a quart every 100 to 200 miles would be pouring smoke out the exhuast.

 

exactly my point. there is nothing from the exhaust at all! My old accord had blown oil control piston rings, and it burned maybe a quart every few weeks, and i could see the smoke from that.

And no, we used the new blue honda antifreeze, still blue, and the oil looks just as oil would. No mixing from what would be a bad headgasket.

 

Idk man that's crazy because that oil had to be going somewhere ... I guess keep and eye on it . Check for oil leaks around the block.

 

No leaks since the rebuild. Was done in october. So been three months now. Spent countless hours trying to figure out where the oil could be going.

 

idk man good luck on this one.