"David R. Conrad" wrote:
> Hello List:
>
> My roadster suddenly started operating on three cylinders last July. Some
> may recall an appeal from me for advice at that time. I again thank those
> who offered opinions/suggestions. My initial diagnostics suggested a bad
> valve in #1 cylinder. That *is* what it turned out to be, a triangular
> shaped chip out of the exhaust valve of #1.
>
> Slowed down by heavy involvement in some home improvements, I finally got
> the head off and to "Akamai (meaning 'da best!) Machine" for
> reconditioning. Just after I left it with them, they closed down the shop
> for a 2-week vacation. After a few delays in getting the parts (some
> associated with the transportation delays after Sept. 11)
>
> Finally got the head back from Akamai Machine last week. Believe that
> they did an excellent job. I put the engine back together last weekend
> with high hopes that the car would run even better than before; it had been
> running well before the valve failed.
>
> I adjusted the valves to .020 (cold) and performed compression checks. I
> thought the results were quite good. "Dry" the mean value was 133 psi
> (+1, -2), very consistent for two checks, and with 10cc of oil added, the
> mean value was 145 (+/-) 3 psi.
>
> I made no changes to points and timing since it had been running well
> before the valve failure.
>
> Then I went to start it (full of confidence). Was I disappointed!
>
> Very hard to start, and when started, it ran very irregularly, with
> definite missing and occasional backfiring. It suggested that the timing
> was off. The distributor hadn't been touched!
>
> Checked the dwell, and it was 59*, higher than when I had set it, maybe
> influenced by the fact that the rpm had to be ~15k to keep it running.
> (though I thought dwell was not rpm dependent). Anyhow I reset it to 50*
> Then I tried adjusting the timing about 5* each way, advance/retard.
> Seemed to run a little better at 5* retard (that is, rotating the dist. 5*
> CCW--maybe that's advance, I don't remember).
Dave,
Did you put in new spark plugs?
Did you check the plug gap?
Did you get the plug wires back on in the right order?
Are all of the plug wires seated properly?
If you took the head off, did you get the intake manifold
to head gasket on tight with no leaks?
Did you say the engine smoothes out at a higher RPM?
If so, could be a vacuum leak at the intake manifold.
Bob
67.5
Moscow, Idaho
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