Tim:
I'd suggest a thorough cleanup of the carb, and check/replace the main fuel
filter. It sounds like the float valve is not seating correctly allowing
the float level to be way too high flooding the rear cylinders. Also make
sure your fuel pressure is not too high. If you are running the stock SU
fuel pump, this should not be a problem, but if you have some kind of
aftermarket pump, this could be your culprit. The DCOE likes lots of low
pressure fuel. 3.5-4 lbs maximum fuel pressure.
When cleaning out a DCOE all you really need is a gasket kit, and an inlet
valve. Don't buy a rebuild kit, these include the float and other bits and
are cubic $.
The carb is very easy to dismantle to where it can be cleaned. Leave the
throttle spindles in place and just shoot cleaner through the ball bearings.
Don't forget to clean the inlet filter in the carb top cover. Check the
float chamber for rust and scale. You may have rust in the fuel tank which
is causing the float valve to not seal, in which case a better filter may be
needed.
For the MGB you can get by with the smaller float valves, but chances are
all you need to do is clean the one that you have.
The DCOE is simple, and pretty bulletproof, so don't give up.
good luck
Kelvin.
> -----Original Message-----
> From: Tim Baxter [mailto:baxter@gretschpages.com]
> Sent: Monday, January 20, 2003 8:25 PM
> To: mgs@autox.team.net
> Subject: DCOEs and misfiring (long)
>
>
> OK, let me give some background. As some of you may know, a
> few months
> back I bought a non-running BGT and have been nursing it back
> to life.
> This particular B is fitted with a Weber 40DCOE, which was so gunked
> up when I bought the car it wouldn't run. A thorough cleaning later,
> and I've been running ever since.
> Until last week.
> Now, the DCOE has never liked cold weather. I've since found out I
> probably didn't have the timing where I should have, but that's not
> really the point here.
> I was nursing the car home from work one very cold night, it was
> coughing and spitting, and then it seemed to badly lose power.
> I later discovered 3 and 4 plugs were REALLY sooty and were not
> firing. It appears the rear barrel of the carb is dumping WAY
> too much
> gas into those cylinders. Front plugs were fine. After changing the
> plugs, it appears I got #4 to work again, but not #3. I pulled the
> carb, found more gunk, and thoroughly cleaned it again. Also, I seem
> to have gas coming out of that barrel at the front of the carb. I
> fiddled with the float today, and MAY have fixed that, but I don't
> trust my float needle, and I don't know which one to buy.
> Still nothing on #3.
> Anyway, what should I check, what should I buy, what Weber parts are
> appropriate for my use, and what tips can anyone offer?
> All ignition parts are new, but hey, if anyone has tips there, I'll
> take 'em. I'm tearing my hair out. I just want my B to run!
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