With encouragement from folks on this list, I rebuilt the Webers on my '67
S3 Elan & it no longer is running too rich. (Put main jets & needles/seats
back to stock sizes & fixed a leaking choke.)
The original problem was constant spitting through the intake and an
occasional backfire at steady speed. This has been reduced to occasional
(but frequent enough) instances of the same symptoms. Under load it's fine,
and idle isn't too bad.
The car seems to have an infinite capacity to provide exciting diagnostic
opportunities, and here is the latest. I would appreciate any ideas you
have regarding the current one.
The ignition seems a bit out of whack. Dwell shows as 80-83 degrees and
point gap has little effect. I've tried gaps from .011 to .017. The cars
tach doesn't work but the tach on my meter shows obviously incorrect
readings of 1900-4500 rpm at engine speeds that I think are about 500-1500
rpm. I tried the meter on another 4cyl & it appears ok.
The distributor is original (I think) - early type with wires out the cap
at 90 degrees. Points, rotor, condenser, and coil are all new. The cap
itself looks ok. No cracks or tracks. Plugs are new. Plugs wire resistance
& continuity tests ok.
The distributor shaft has some slop in it. It's not easy to measure but
appears to be about .008 side-to-side at the cam - may be less but not
more.
Also, the distributor is mounted 180 degrees from (what I think is) normal.
The plug wires face forwards. The shaft is evidently rotated 180 as well,
and plug wires moved to compensate. I can time it ok. Firing order is
correct. I've never seen this done, but guess it's ok.
I think the engine is basically stock, although it has what I think is a
late head. There's a web between cyls #2 and #3. (There's the letters "JC"
stamped - not cast - on the top of a machined surface of the web. Don't
know if that's common.)
Compression is good on all four.
I'm hoping that someone has some ideas regarding the odd dwell and tach
readings, and an indication of how much side-to-side motion in the shaft is
"too much".
Thanks and I promise to try to shorten future notes.
John Coelho
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