Trevor Boicey wrote:
>
>
> You can probably pin the problem down with some simple
> DIY tests. Take a small gas can to the corner station
> and buy a few liters of diesel fuel.
>
> Spin the engine until all the pistons are about the same
> height, and fill all the bores with diesel fuel. Time how
> long it takes for the fuel to run out. It should stay in
> there for an hour or better, but likely more obvious
> will be that 2 and 3 might be empty when 1 and 4 are still
> full.
>
> Other test, balance the head on something so it is
> upsidedown and flat, and do the same test with the
> combustion chambers, fill each with diesel fuel or
> paint thinner and see how long it takes to drain. These
> should hold overnight, but a bad valve will drain
> before your eyes.
>
I took Tevor's advice and gave it a try with the diesel fuel. I
positioned the pistons 1/2 way up the bore and filled the rest with
diesel fuel. The second cylinder drained in about 1.5 hours,
followed shortly by the number 1 cylinder. After about 2.25
hours the number three cylinder was empty. Number four, the
cylinder with the good compression had only leaked down about 1/2".
After 5 hours cylinder 4 had leaked at most 1 inch, if that. Now
the cylinders drained in the following order, 2,1,3 and 4 held
the diesel.
I also filled the intake and exhaust ports with diesel. None of
the exhaust valves leaked. The intake valves on cylinder 1, 2, and
3 leaked. They leaked slowly and the ports never drained.
Looks like I will be pulling the engine over the next couple of
weeks and getting it rebuilt. This really should not suprise anyone.
The only problem I encountered was how do I get the diesel out
of the number 4 cylinder and the head ports. Being the day after
Thanksgiving I decided to use my wife's turkey baster. Worked like
a champ. No I did not return it to the kitchen, and yes you all must
keep this a secret.
Bill Gilroy
77 Midget - about to lose its engine
90 Shar-Pei
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