Hi list,
I have been off the list for several months having finally gotten my
roadster back together and getting other projects finished. But after
driving it now for several months, I'm seeing blue smoke out the tail pipe
as described below.
I rebuilt my whole 1970 1600 car over the past 2 years. I changed the stock
1600 engine to a stroker. 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.
Last night I checked the compression for the first time and found cylinders
1 and 4 were at arund 110 psi, cylinders 2 and 3 were at 145 psi. The plugs
were somewhat fouled and oily. When I put in some oil into each cylinder and
repeated the compression test, each cylinder psi increased about 10 psi from
the previous values.
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.
I haven't checked the valve setting clearances lately (I did at 1000 miles
or so).
Les and Dennis said that the valve clearance for this M42 cam should be
0.018" intake, 0.020" exhaust, hot. If cold, reduce the gaps by 0.002". The
M42 cam is supposed to have Lift=445 and Duration=270 (whatever that means).
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?
I'm not sure what to do next, other than to check the valve clearance again.
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 Wilson 1970 1600 stroker 28383
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