ok i searched, i did alot of research but no one seems to have the SAME exact problem as me.

i have a b18c5 and when cruising around the motor seems fine, no smoke, no smoke at idle, no smoke when revving. BUT if your at say 4000rpms and you let the car enginebrake in gear. you know? kinda like just let it idle down, and then hit the gas it PUFFS blue smoke. and then after driving normal if you floor it, it smokes in vtec , BUT after it smokes and you keep it pinned it seems to clear it self out and does not smoke until you drive like an old lady again.

so im thinking its valve seals.
but some people say rings, but if it was rings wouldnt the car run like ***, and wouldnt i have oil all over my plugs? and if it was rings wouldnt it smoke ALL the time and not like clear out after you get on it.

 

Having the Same Problem...

I think U should compression Test ur car, First...

 

subscribed. my car runs great. I see no smoke from the tail pipe. I have no oil leaks. however, I have to add oil every 700 miles or so.

this is on a b16a2 with ctr cams/pistons and about 28,000 miles on the build.

i'm curious to hear what other people think about your situation before I dig in to this.

 

Whats the weight of the oil that you are running. I would change to a different weight oil and go from there. This is for (( o )( 0 ))

 

I deal with this all the time on oem motors. B16A, B18C. 95% of the time its the bottom end....

cyl wall damage, cyl out of round, rings not sealing good....

Sometimes switching oil brands and weights around helps a little...

 

I think whats happening is while your engine braking from say 4k to idle, vacuum is HIGH. I think this is when manifold vacuum is strongest on the crankcase.
Sucking all this oil vapor from the block starts pooling inside your intake manifold. I think #3 is the one that gets most of it. When you Hit VTEC again,the rush of airflow pushes it down the port and it gets burnt and smokes...
Leaking valveseals generally will smoke at idle(high vaccuum) and clear up after driving for a bit. Rings will smoke mainly under WOT...

If you think this is whats going on,you can clean reroute your pcv or set up a temporary catch can to see if it helps. Re-route your pcv hose and plug the manifold. This will prevent the engine from ingesting its own oil.
Or you could remove your throttle body and inspect.

 

expletive it, some people say its rings some say its valve seals, every instinct in my head says its valve seals. well screw it, rebuild time. bigger and better. im not gonna play the guessing game. burning oil is embarassing.

 

how often do you have to add oil. if not alot i would run a catch can like said before and see what happens

 

I run pennzoil 5w30. I don't believe synthetic is necessary for my setup. however I am open to changing weights or brands. suggestions?

however after reading PyroProblem's and 4g hatch's post, I think i'll put my catchcan back in for a while and see it that changes things.


Modified by ( o )( o ) at 11:15 AM 11/29/2007

 

i would try 0w40 euro oil from mobile 1

 

it doesnt burn thru much at all, but i already capped off the intake nipple to the PCV system, and that did help a lil, BUT its still got blue smoke.

 

and i was always taught that valve seals smoke at first start up then go away after it warms up and wont smoke until you get off the gas and on it again.

and i was taught that rings will smoke all the time. not just under WOT.

 

Look in your intake manifold to see if its all nasty and oily and whatnot. If it is id say your getting oil in your intake via pcv system. I think #2 or 3 gets it the worst, i forget which one.
If your intake is CLEAN, then you can rule that out.
How many miles on your head(valveseals)? The very few at ive seen leak had WELL OVER 100k miles.
You can take your intake manifold OFF and look at your valvestems and ports and see if theyre excessively oily. If not then its probably not your valveseals.
But the first thing id do is LOOK IN YOUR INTAKE

 

Does it only smoke after you engine brake/engine decel/coast in gear?
Bad rings should smoke the worst at WOT, however they can smoke at idle too depending on th severity of blowby...

 

At least do a compression test. A leakdown test would probably be nice too.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PyroProblem &raquo;</TD></TR><TR><TD CLASS="quote">Does it only smoke after you engine brake/engine decel/coast in gear?
Bad rings should smoke the worst at WOT, however they can smoke at idle too depending on th severity of blowby...</TD></TR></TABLE>

yes it smokes AFTER i decel, and if i floor it it will smoke in higher RPMS, and will go away if i stay on it, it seems to clear up the more i floor it, but then when i drive normal again it will smoke when i floor it.

also the PCV is eliminated. i plugged it up for the time-being. it did make the situation ALOT better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rochesterricer &raquo;</TD></TR><TR><TD CLASS="quote">At least do a compression test. A leakdown test would probably be nice too.</TD></TR></TABLE>

Good advice right there. A compression test and a leakdown will give you some insight on the problem. Do that before anything.

I would most def try running a heavier running weight oil.

When I was boosted, I had a similar issue on decel and it was my valve seals.

Goodluck.

 

someone told me a leakdown wont tell me if the oil rings are bad. and it also wont tell me if the valve seals are bad, so its pretty pointless.

 

I have a simaliar problem with my car. It smokes when in it crosses over into vtec. I use mobil 1 sythentic 5w30. In 3000 miles it only uses a quart. I did a compression check and it was 240 all the way across. I also am running a catch can by way of dissableing the pcv valve.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prettylew &raquo;</TD></TR><TR><TD CLASS="quote">someone told me a leakdown wont tell me if the oil rings are bad. and it also wont tell me if the valve seals are bad, so its pretty pointless.

</TD></TR></TABLE>


That is true!

Unless there is serious piston or cyl wall damage. You could have no valve seals at all and it will not shown on a leak down or compression test! Lots of so-called mechanics come in to suggest ideas but don't know much about the reasoning behind them.

I'm still betting on rings. Very common issue on these motors after a few years.

 

here in lies my problem. lol.

everyone says its common after a few YEARS lol
this motor was just built 6k miles ago. so im thinkin either someone tried to clean the head with break clean and ruined the valve seals. or the rings didnt break in right.

but it has ALL the power. its dam fast and runs fine. if the rings didnt break in right wouldnt i have low compression and no power?

or maybe someone screwed up when installin the valve seals. perhaps they arent seated all the way. i just dont know.

but APPARENTLY there is no way to check that on honda motors.

a leakdown wont show u **** but leaky compression rings or valves.

and a compression test is almost useless.

so the only real way to find out the problem is rip apart the motor i guess. AWESOME.

 

Long story, best example I could think of.


Many years ago a friend of mine had a machine shop assemble a short block. B16a, with all stock parts except .25mm oversize oem ctr pistons. He broke the motor in very gently and ran off a chipped ecu. After a while he started running it harder and harder. Everything was great except the motor was using oil and was smokey after a decel or long idle.

This became very annoying and after a season of trying pcv setups and valve seals and whatever else we could think of, the motor got pulled.

Well it sat for two years and then one day we decided to take it apart. Everything looked beatiful inside, no sign of any problems. We put some new type r pistons in with new oem rings. Broke the motor in hard and tuned it right away. Well let me say that worked like a charm and never smoked again. No other changes. Finally, the original 1991 b16a oil pump gear broke (UR pulley) and we retired it a couple months ago.

 

ohhhhhh, thats funny cuz this kid said he broke the motor in gently too. maybe that is my problem. maybe ill just re-ring it and drive it hard.

 

Oh crap!
If he babied it during break in, then the rings missed there chance to get seated!
You want some pretty good pressure against the backs of those rings if you want them to seal well! I agree that that is most likely the problem
You are correct also about compression and leakdown tests. Neither will tell you the valveseal condition.

 

I think your buddys problem started with that chipped ecu