Excessive oil consumption question
 

So my 91 civic (D15b8) is burning one qt. of oil every 80 miles. I did a compression test and got 170 on all cylinder and I have 18.5 inches of vacuum at idle. Also there is a new pcv valve on it. So before I condemn the valve guides and stem seals is there anything that I am missing?

Re: Excessive oil consumption question (red91hatch)
 

Have you checked for leaks?
Does your car smoke?
I know you said you did a compression test but if your car smokes is because you have bad piston rings. I had the same probelm on my ls. I had good compression but it was gusleling my oil. Which I found out it was burning it. Took tha motor appart replaced tha piston rings and it was all good.

Re: Excessive oil consumption question (reyracerx)
 

Yes it smokes but it is really hard for me to see it because I have 5% tint on my back windows. I think that I will be redoing my compression test because I just drove it and I could see it smoking (black) when I was at high way speeds at WOT in forth gear. It smokes the worst when it is cold. What kind of vacuum do you guys have at idle? If the rings were bad wouldn't I be seeing low vacuum or get a inconsistent reading when doing a vacuum test at idle?

Re: Excessive oil consumption question (red91hatch)
 

I redid my compression test and got 150 on all cylinders. It only smokes on acceleration so my thinking would be rings or pcv system, but if I have good compression on all cylinders what are the odds that just the oil rings failed? The pcv valve is in working order. Is there any where that I can get a better diagram of the pcv system? Where else in the pcv system could there be issues? Thanks for the help ahead of time.

Re: Excessive oil consumption question (red91hatch)
 

That still pretty much says rings.....But the lesser of the two evils is valve stem seals......do those first, for the reason that it doesnt include tearing the motor down

In the last 3 honda engine ive rebuilt for oil consumption, they all had great compression but upon dissasembly i found the oil control rings were gunked up and seized causing the oil consumption

Re: Excessive oil consumption question (red91hatch)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by red91hatch &raquo;</TD></TR><TR><TD CLASS="quote">I redid my compression test and got 150 on all cylinders. It only smokes on acceleration so my thinking would be rings or pcv system, but if I have good compression on all cylinders what are the odds that just the oil rings failed? The pcv valve is in working order. Is there any where that I can get a better diagram of the pcv system? Where else in the pcv system could there be issues? Thanks for the help ahead of time. </TD></TR></TABLE>
ike i said bro. oil rings can have tha slightest damage but enough to burn your oil but still have great compretion https://honda-tech.com/forums/images...s/emhammer.gif lol

so if u say at acceleration it smokes n the pvc valve is working then its the rings for sure. do a test... haul ass in second gear n keep the rpms up high for like a few seconds then come to a complete stop right away n smell. if u smell burnt oil take your motor appart in change the rings! https://honda-tech.com/forums/images/smilies/emthup.gif

Re: Excessive oil consumption question (SIred91)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SIred91 &raquo;</TD></TR><TR><TD CLASS="quote">That still pretty much says rings.....But the lesser of the two evils is valve stem seals......do those first, for the reason that it doesnt include tearing the motor down
</TD></TR></TABLE>
If you replace only the valve stem seals on an engine that consumes a quart of oil every 80 miles, you're just ensuring that you will have to pull it apart twice instead of once. Even if the valve stem seals are in awful shape, sealing those weak points up will only cause even more oil to blow past the rings.

The number one cause of oil consumption in a Honda is seized oil control rings. If you don't address this, you're just pissing into the wind. Might as well do it right the first time and do a ring job and replace the valve stem seals all at once.

Re: Excessive oil consumption question (Targa250R)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Targa250R &raquo;</TD></TR><TR><TD CLASS="quote">
If you replace only the valve stem seals on an engine that consumes a quart of oil every 80 miles, you're just ensuring that you will have to pull it apart twice instead of once. Even if the valve stem seals are in awful shape, sealing those weak points up will only cause even more oil to blow past the rings.

The number one cause of oil consumption in a Honda is seized oil control rings. If you don't address this, you're just pissing into the wind. Might as well do it right the first time and do a ring job and replace the valve stem seals all at once.</TD></TR></TABLE>
https://honda-tech.com/forums/images/smilies/emthup.gif https://honda-tech.com/forums/images/smilies/emthup.gif

Re: Excessive oil consumption question (reyracerx)
 

Yeah I will be rebuilding it or getting a new motor for it.