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Hi. So I have a 1994 honda civic cx with a d15b8 motor with ~320,000 miles. at about 310,000 I took the motor out, out new rings seals, the whole 9, honed the cylinders with nice cross hatching, brought the head to a machine shop and they changed the valve seals, resurfaced the head made it look new. Since all this, it always kind of leaked oil in the front drivers side near exhaust manifold. So recently I decided I'd re-torque the head bolts one day after changing my oil. I did that and when I went to run it, it smoked like crazy. kind of blue smoke pouring out of the exhaust pipe. I then took the head off, changed the head gasket and put it all back together. Same thing, pouring out smoke. I have recently taken the head back off and brought it to the same machine shop to see if anything is wrong, so far they have only said the cam seal doesn't look that good, I can't remember if I changed that out or not, but nothing on the head would indicate burning oil. I forgot to do a compression test and leak down test before removing the head, but if the shop cant find anything Ill buy another head gasket and an intake gasket and try those tests.
If anyone else has any ideas on where I should look or if it might not be the head and I am missing something that would be great. I just thought it was odd that once I re tightened the head bolts everything went haywire on me.
Tell me the exact procedure you used to re-torque the head bolts, this shouldn't have been necessary and if not done properly could warp the head or cause head gasket sealing issues.
I tightened down the right side of the motor in a criss-cross style, following the book, but I just checked the other bolts on the left side of the head and went a little bit more on the side that was leaking. Do you know anything about "stretching" head bolts? I heard that could be the case and it wouldn't seal right after that. Granted these are the original head bolts from 94, so I ordered new ones to be sure.
I would seriously consider having that head checked at this point. I dont know what book you looked at for this but Honda heads are tightened from the center out....See Below
Any other way and Id be afraid the head may have warped. Or if your very very lucky just caused massive sealing problems and immediately blowing your HG
You also didn't describe with great clarity exactly how you went about "re-torquing" the head bolts.
Did you loosen any bolts, if so, how much and in what order.
Then you state you over torqued some bolts (leaky side)....
I've got the feeling you warped your head.
And I second Ryan's post, valve guides and bore and hone.
I assume you replaced the bearings since you had the pistons out, did you do all the crank shaft checks and do the main bearings too?
There is so much information not disclosed or skipped over.
I did bring the head to a machine shop. They said there was absolutely no sign of crack or warping on the head. Only thing was the cam seal wasn't pushed in. That is most likely where I saw the leaking from. But I really cleaned the head and block, new intake gasket, new head gasket, and new head bolts and everything seems to be fine now.
For the other comments, when I redid the motor, everything checked out, the cylinders were not egg shaped as I measured them and they were all within the tolerance. Originally when I did this I brought the head in to get serviced, new valve guides, seals, resurface of the head etc. I also honed the cylinders, making good hatching marks.
I did all the bearing etc and made sure the crank was good. I changed pretty much every seal in it. When I re-torqued, I just tightened a little bit more down on the bolts, maybe 1/4 turn. My theory, which I have read but don't know if its true, is that the head bolts got "stretched" and didn't make a good seal after that. Otherwise it was the intake gasket and it was actually burning antifreeze.