Re: Puzzle: Oil Burning 4Kcsq

[zm@mhcnet.att.com (Zafer Mehmood [209])]

> 
> This is a posting for a friend.  He has a 4kcsq with
> 286K on the clock.  He lost his cooling system a while
> back and didn't get it stopped in time.  He had head
> warpage at that time.  The oil heated and foamed as well,
> so he says.  Anyhow he lost oil pressure.  After getting
> it all put back together, he now has hydraulic valve clatter
> which last much longer than ussual, and has progressively 
> higher oil consumption.  Now up to 150 miles / quart!
> Compression is at 170 for all five cylinders.  No blow
> by is noted with the fill cap off.  

I've heard that excessive oil consumption is not uncommon on an
old engine when only the top half (head, valves) are rebuilt. The
reasoning is that with a high mileage engine the piston rings
have worn somewhat and when you suddenly increase the compression
by making the top half tighter, the oil gets sucked past the weak
piston rings (during the intake stroke) into the cylinders and
gets burnt.

Zafer

-----------------------------------------------------------------
Zafer Mehmood				   AT&T Bell Laboratories
zm@mhcnet.att.com			   Murray Hill, NJ