whereiscarmensandiego

okay iv done a full rebuild on my d15b8 with a d15z1 head and the thing still smokes at idle at if u rev the crap outa it u cant see the smoke while driving but i think it is still there.

i have rebuilt the entire lowerend with new rings,bearings,oil and water pump. and i just got done redoing the entire head with new springs and valve seals.

and it still smokes and wont stop no matter what i try. im new to honda motors but im an experienced mechanic and have rebuilt lots of motors so i know that a part wasnt put in wrong.

the smoke is more on the white side then dark blue but i never burn any coolant and i have no bubbles in the rad with the cap off.

what could it be? what else would make it smoke?could it be the head and block combo?

boostedcivicsir

did you hone it? how did you offset the compression and oil rings? are the compression rings in the correct groove and installed right sided up?

whereiscarmensandiego

i had the block hot tanked and honed by a shop and i did the offset per the haynes manual and there in the right grove and right side up i triple checked all of this before i bolted it up.

when i first got it it smoked so bad that u couldnt even see behind u and wasnt really drivable. after i did the bottom end it is alot better alot . it only does it when u first accelerate and it u go above somthing like 5 or 6 grand rpm. i thought it might be the valve seals so i just replaced them and it still smokes. it only has about 120 miles on it since rebuild but im not sure if that has anything to do with the smoking. ?possibly the rings havent seated yet?

oh and i after i got it back together just today i got a cel code. it just keeps doing long flashes over and over so i think that means a bad o2 sensor so could that have somthing to do with it?

whereiscarmensandiego

anyone else have any ideas?

fmrprojects

did you chek your valve guides? were your valves bent at all? cracked valve guides will cause a motor to smoke

blk92_d16

So you've only got 120 miles on the motor now on a fresh rebuild? Which break-in method did you use? I'm hoping you used assembly lube on the metal-to-metal contact surface during the rebuild?

whereiscarmensandiego

the valves arnt bent and no i didnt check the valve guides because i didnt know they could cause smoking only valve seals. and yes ofcourse i used assembly lube the motor is put togther very well.

some more info as well iv got no cats and a headback exhaust with 2 1/2'' piping a resonator and a larger canister.

and just yesterday when i assembled everything back i ahve a check engine light. it keeps blinking long blinks over and over and never stops. so i take that to be a bad 02 sensor? and i ahve a cx hatch and it has that little green arrow that tells u to upshift well mine isint working now

whereiscarmensandiego

also i get lots of black flakes on the grass if i rev it in the yard