> Today, I took the car out for a drive and noticed the following
>symptoms. I am not a mechanic, so please bear with me. Again, for
>the first 10-15 minutes that car seemed fine. There was no smoke that
>I could see from the driver's seat and the oil pressure was a little
>above 50 when the car was idling and above 75 when at 3000RPM (THIS IS
>GOOD). Then I started to notice the smoke. A little at first, but
>more as I continued to drive. Also, the oil pressure started to drop
>so that by the time I stopped it was about 20 when the car idling and
>about 50 at 3000RPM (THIS IS VERRRY BAD). The smoked was more evident
>when I was accelerating or engine breaking. The only other weird
>thing that I noticed was that when I accelerated the oil pressure
>dropped for a second or two. I don't know if this is normal.
No, it's not normal.
>The only other relevant information about the car is that I had the
>head totally rebuilt about 1000 miles ago. I put a significant amount
>of money in it, so please don't tell me this is serious. I am hoping
>that one of you will tell me that the head is not torqued down enough.
Could be. If you've got a loose head, it may be warping when warm
enough to allow high-pressure oil to get past the gasket into the combustion
chambers. Check carefully to make sure the engine isn't overheating, and
that the oil level isn't horribly low. I suppose it's possible that there
could be excessive blow-by forcing oil into the carbs, but that seems
unlikely.
The head may be warped or loose. You may have overheating problems
which have warped the head (that would explain the loss of oil pressure,
which I'm not sure would be totally explained by even fairly major seepage
into the cylinders, though maybe). You could have a dying or dead water
pump causing the overheating. You could have a blocked cooling passage or
collapsed hose causing overheating.
Oil is getting into the cylinders. That means one of: past the
head gasket; past the valve guides; past the rings; or via the crankcase
ventilation attachments to the carbs.
You could try retorquing the head (back off each one 1/4 turn before
retorquing it, in sequence - otherwise you won't get accurate readings).
Only try this if it isn't overheating or after you solve the overheating.
Don't forget to reset all the valves after the retorque. However, I wouldn't
be suprised if a head removal, new gasket, and perhaps a head shave are in
the cards for you. Just make sure it's not a simpler thing first,
like torque or the breathers to the carbs. Pray you don't have a cracked
head or block, which might also cause the problem.
--
Randell Jesup, Scala US R&D, Ex-Commodore-Amiga Engineer class of '94
Randell.Jesup@scala.com
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