Spridgeteers,
I don't post often, more of a reader than a poster, but I've run into a
problem that requires some fresh opinions because I don't have one on this
topic.
I have a 1977 Midget that has had the Weber 2 barrel downdraft conversion
applied to it prior to my owning it. The Weber was rebuilt last year by an
experienced mechanic and everything was running better than ever. This year
I have only taken the car out on a few short (50 Mile max) jaunts. On the
last trip it ran pretty poorly after sitting at a car show for nearly all
day. Finally just before home it began to run properly after being moved
along smartly in 3rd gear for a bit. It seemed like one cylinder was firing
very erratically.
Yesterday I pulled the spark plugs to see what I could see, and the plug
coming out of cylinder number 1 was covered in black soot while cylinders 2,
3 and 4 were nice/normal. The center insulator on #1 was all covered in the
soot (flaky, black , not oily stuff) and the motors manuals say this is an
indication of running too rich in that cylinder, But why only that cylinder?
I went down to the auto parts store and bought 4 new plugs, all AC's but I
bought a one level hotter plug for the number one cylinder. Seems to be
working OK for the moment but this isn't my first time with this problem.
When I first got the car, number 1 cylinder would also foul up. A
compression test shows #1 and #4 are getting 160 lbs/sq in. of pressure in
compression while #2 and #3 get about 140 lbs/sq in.
So what is causing number 1 to "load up" the plug? Suggestions? Things I
should check further? Opinions? Ideas?
TIA,
Dick
1977 Midget
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