rings bad, to rebuild head?

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R

racermp

New Member
hey all, i'm new here. just bought a 97 civic ex 5spd last week with 170k miles.


the car is all stock and engine acutally runs strong, just smokes like hell. it didn't when i bought it, but smokes and wown't stop 2 days after. i paid 2700 for it :(

compression is 190-200 on all cylinders but it smokes like hell, (greyish/white smells like gas), oil is black!!!! i changed the oil and did a GUNK flush, still stayin black. but head looks clean from under the oil cap.

new plugs are covered in oil on the tips.

i'm gonna open up the engine this weekend and change out the rings, and probably the valve stem seals, should i rebuild the head?

it's 145 to rebuild the head.

oh also, should i replace the pistonrod bearings? car doesn't knock.


thanks for any help
 
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If the smoke is Bluish/White this is most likely be your rings, Black smoke is running rich, White smoke is coolant with a sweet smell. If it smells like gas than your smelling unburned fuel AKA Hydrocarbons or HC. Okay are you saying your oil goes black lets say less than 1000 miles????
 
yea it gets black within a few miles. and it's burning oil pretty badly. i drove 20 miles, went from full to the low notch. i coujldn't find 20/50 so i putin smoke be gone an 10/40


oh and it's a whiteish/greyish/very light blue. mostly greyish white. coolant is good and it doesn't smell like coolant burning.
 
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you might wanna replace your pcv also if your oil is getting black fast. They are cheap so your not wasting money.
 
cool. will do. i'm gonna change out the pcv first. where is it located? i'm having a hard time finding it
 
It is located between that black breather box below the water traveler and the front of the intake manifold, its a bigger vacuum hose than the fuel pressure regulator hose which are right next to each other. Otherwise its on the valve cover to the intake.
 
hey, thanks, i found it today. it's the hose going directly inbetween the intake manifold. and the pcv is right about the oil filter. hard to get to. but i change it. i put up a video of the car smokin.

 
na doesn't smell sweet or like coolant. it smells like gas. doesn't overheat or use coolant. but there's oil on the tips of the spark plugs. and new spark plugs are very black in 10 miles.
 
Well Do a cylinder compression test if ya can. Cause if your getting sometimes bluish/white smoke that means your burning oil and your rings will need to be replaced. Do you have a catalytic converter, if so you might wanna see how much pressure you get before the cat, called precat. All you do is take the O2 sensor out before the cat and place a pressure gauge that is made for this test and you shouldn't read no more than1.25 PSI. If ya had a good one you would read 0 psi. Also if you found out that coolant was going through the exhaust than say goodbye to your O2 sensors.
 
hey, i did a compression test, it's 190-200 on all cylinders. ihave to get the car ready by monday so i'm gonna try replacing the valve stem seals without takin off the head if i can. if not, then i'm gonna take off the head and probable just replace the rings while i'm at it too
 
I would replace the valve stem seals and the rings with the head off, it will help ya out easier and faster. better safe than sorry, if your gonna replace the rings make sure the gap faces a certain direction as specified in the service manual. and make sure the rings go on the right way and not upside down. They will have either a dot or some type of letter or number to indicate that the marked side faces upwards.
 
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Not jacking the thread just my input. Bro, by pcv you mean valve, hose or the breather box?

I have exactly the same problem. Oil black, black soot from the exhaust, smokes alot, black carbon buildup on the ground after startup. This IS a common problem with hondas. Specially D and B motors. ( don't know about H,K,C whatever) On my motor I have a practically new head btw.

I hope someone has a definite answer to this thread.

O2 sensor?????
 
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Pull the head and inspect.

Carbon build-up on the back of the valves will indicate bad valve seals. Also, if a combustion chamber leaks, some of the air/fuel mixture will escape when it is compressed, resulting in a loss of power and a waste of fuel. These leaks can be caused by burned valves, worn rings, blown HG, worn valve seats, cracked head, slipped timing belt and so on...

I would do a cylinder leakage test on it to find out where it is leaking. If your reading is ' 0 ', than there is no leakage in the cylinder. If it reads ' 100 ' than that cylinder will NOT hold any pressure at all. Listen for air escaping from the engine. If you hear it coming from the oil dipstick tube or the valve cover breather cap than its your piston rings. If air is felt or heard leaving the throttle body, than its an intake valve problem. If its heard or felt leaving the exahaust than its a bad exhaust valve.

Remember, a 20% reading when performing this test with shop air is acceptable, being when the engine is actually running the rings will seal much better and the actual percentage of leakage will be lower. Keep in mind, there should be no leakage around the valves or the HG.
 
hey, i changed out the motor, that definatly solved the problem. lol.

ok so when i took off the intake and exhaust manifolds on the old motor, there was alot of oil in the intake and exhaust manifolds. compression and engine ran good, i'm assuming valve seals. alot of oil in the exhaust, i still smell it buring off everyday ad i've put on 500 miles so far.
 
It could have been map sensor. That would cause you to run very rich, which would in turn cause gas to bypass the rings and into your oil. Happend to me. Also a friend with a BB chevy with bad rings would blacken the oil quick like.
 
true,. the oil did smell like gas. but i'm still using the same old intake manifold and map sensor and all sensors as the old motor. no problems so far on the new motor

except for a slight hesitation/bog between 2500-3000 (then big surge of power at 3000 rpm), not sure.
 
LudeBoy said:
It could have been map sensor. That would cause you to run very rich, which would in turn cause gas to bypass the rings and into your oil. Happend to me. Also a friend with a BB chevy with bad rings would blacken the oil quick like.
Click to expand...

Gas cannot bypass rings. When the spark plug fires and ignites the a/f mixture it is then burned and forces its way down. Please don't give false information.
 
There is a such called Hydro-Carbons which is unburned fuel which will indicate a rich mixture taking place inside the combustion chamber and than out the exhaust valve which could possibly get through the valve seals?????
 
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