"WILSON,BOB (A-SantaClara,ex1)" wrote:
> I bought the parts from Les and Dennis: New
> pistons (flat top, 0.040" oversize), crank, conecting rods, valve seals, and
> cam. The cam was called an M42. The valve cover "breather port" now vents
> simply out through a tube to under the car (no pcv valve).
>
> After about 4000 miles on this new engine, I am still seeing blue (I think
> it is blue) smoke coming out of the exhaust when I drive down hill, in any
> gear, using the engine compression to slow the car.
>
> All that I can conlude is that I probably have two probems:
> 1) valves in 1 and 4 seem to be leaking.
> 2) somehow, oil is getting into the cylinders.
>
> The only thing that I can think of that might have been wrong was that the
> gap on the rings, when on piston and inside the cylinder, was several
> thousandths larger than what was stated on the paper that came with the
> rings. (Deves rings). I bought the rings, flat top pistons, connecting rods,
> crank, M42 cam, etc from Les and Dennis. All the parts were new and seemed
> ok.
>
> Carburators are new Solex 40mm.
>
> So, does anyone have any experience with burning oil, especially when going
> downhill using engine compression to slow the car?
>
> PS, I connected my compressor to the spark plug hole and when the piston was
> at the bottom (it went down there when the pressure was on) air was leaking
> out through the exhaust. I think that makes sense?
Bob,
When you installed the piston rings, did you line up all
the end gaps or did you stagger the gaps around the piston?
Using engine compression to slow you down will create
vacuum that will suck more oil into the cylinder and can
mean that oil may come from the valves or piston rings.
With 1 and 4 lower in compression the rings may not
have seated properly.
Is the engine running rich? This can occur easily with solexes.
If so the extra fuel could wash the rings and cause seating problems.
Are all of the plugs wet/oily or just 1 and 4.
Were new valves or valve guides installed?
This is probably the problem area.
Bob
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