About the middle of last week I started noticing an occasional miss in
my snake at higher rpms. Since it was a warmish that day and I hadn't
noticed it in the morning, I thought is was just a bit of vapor lock.
Friday morning I drove the car to work because a few people who wouldn't
be able to make it this Thursday still wanted to meet at the Britannia
for lunch. It was fairly cool in the morning but the miss was even more
noticeable. So much for my vapor lock theory. Actually it was more
like intermittent total cut-out than just a couple of cylinders not
firing. It seemed like classic fuel starvation symtoms to me; like when
the tank is nearly empty or when the fuel pump is acting up or perhaps
just dirt in the line. In fact, dirt was exactly what I suspected
because I knew for a fact that my tank was crudgy inside and the fuel
filter I had replaced the previous weekend had been filled with lots of
this crud. So, I took off a bit early for lunch to replace the filter.
But the less-than-a-week-old filter didn't look too bad. There was a
hint of residue at the bottom of the filter bowl but the filter itself
looked clean. I replaced it anyway and pulled the line between the carb
and the fuel pump thinking a chunk of something-or-other may have gotten
past the filter. I also ran a quick un-instrumented fuel pump test.
Everything seemed okay, but without an actual pressure/volume
measurement, I couldn't be sure.
Hoping things would clear up, I took off for the Britannia. The car
idled fine and seemed okay as long as I kept the rpms below about 1500;
hard to do even in slow traffic. By the time I got to the Britannia I
was wondering if I'd make it back to work. Oh well, I'd worry about
that after lunch.
For the first few blocks the drive back to work wasn't too bad though
the intermittent stumbling was noticeable every time I tried to
accelerate. But by the time I got back to HP I was driving in the
extreme right lane and was pretty much limited to below 1200-1500 rpm.
I decided to continue on home and switch cars.
Saturday I made a quick trip to a nearby auto parts store and picked up
a carburetor rebuild kit. Unfortunately they didn't have a float in
stock so the rebuild had to be postponed for the time being. Well, I
still needed to flush the cooling system and I decided I could fiddle
around with the problem at the same time since this would involve
running the engine for extended periods. My gut feeling was that it
was the fuel pump, which I really didn't want it to be because I'm
planning to switch to an electric pump, but not until I have the tank
boiled out. And I don't want to get the tank boiled out until I get my
share of what's left of of this year's roadster weather. To shorten
this getting-to-be longest story, while revving the engine during
flushing, it stumbled badly and huge billowy clouds of black sooty smoke
came out of both exhausts. Bingo, carburetor. The problem wasn't fuel
starvation after all but flooding.
Roland Dudley
cobra@hpcdcsn.cdc.hp.com
CSX2282
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