Rebuiling Heads - Advice please (Long)

jpsandberg

Registered User
Hey everyone!
(this is a 2 parter)

I am considering rebuilding my heads. Here is why:
Almost every time I start my car after it has sat for 10 minutes or more, it blows out a puff of blueish-white smoke (for about 1-2 seconds) I used to have this problem only if it sat for a longer period of time (8 hours or more), but it has progrssively gotten worse to the state it's at now. I also use/replace 2 quarts of oil between oil changes. I do not notice any smoke when driving, just at start-up (and very rare occasions if I rev to high RPM's while it's in park)
From earlier posts hear, I was told this could be from leaky valve guides? Is it possible its also Rings? (I am betting on the valves).
I was also told that leaky valve guides could let oil leak down and pool in the cylinders while it's sitting, and that's what is burning off when I cold start it.... Sound right?

I had the motor rebuilt about 40k ago (top and bottom) ever since that time it used almost a quart of oil between changes. (at that time, I was told by the mech. it's supposed to do that with these cars, even after total rebuild and believed that to be true..)

Now my questions are:
1. Is what's happening a resault of bad valve guides, Rings, or both? Also, how is a good way to tell before ripping it apart (if possible)?
and MAINLY
2. If it's the valve guides (well same with rings I guess), and I am going to have to pull the heads, what are some less-expensive work I can have done to the heads while they are off to give more performance? (I have fresh-air intake, 75 C&L MAF, and SCP exhaust w/high flow cats, res, etc)
I am curious: Porting? How much? anything else while I am at it? Price guesses? Head studs (what are they also?)

I am thinking the rings should be OK since the motor "only" has 40k on it since rebuild..

Thanks for you time, and look forward to replies!

Jonathan
 
two ways, leave heads on or take them off, you can check the guides while the heads still on(kind of check, not accurate). The guy obviously left the old valve seals on and might of soaked them in solvent
 
Sounds to me like whoever did your rebuild may have taken a shortcut or two, 4 stroke engines are supposed to burn gas and air mix, not oil. Even if the do burn a little it shouldn't be enough for you to see it.

I'd say you have guessed properly on the source of the smoke but.... You can check the rings by doing a compression and leakdown check on the motor without removing anything but the plugs. If the readings are all about the same in each cylinder and they don't leak down very quickly then your rings are ok. Checking the plugs for black residue should tell you which valve seats/guides are leaking.
 
Last edited:
Thanks, and a question

thanks guys. Will try the compression check and visual inspevtion soon. Is there an easy way to do compression check? I can't even SEE the spark pulgs!

Also, Anyone have any suggestions on what I could do to the heads to give better flow/performance? (specifics?)
 
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