I'll add my piece on Q-Jets, about the leaky fuel bowl. Symptom of the
problem is an empty fuel bowl after letting it sit a day or 2 without
running; you have to crank the starter 10 or 15 seconds to refill the
fuel bowl before it will start (unless you have an electric fuel pump).
Problem is these carbs have holes, I forget how many, in the bottom of
the fuel bowl section, I think they're core support holes to facilitate
the casting process. Rochester presses soft plugs in to seal them, but
they frequently don't seal or lose their seal over time. If they don't
seal they allow the bowl to slowly drain into the intake manifold.
I've read of several cures, been afraid to try most.
One is to replace the plugs with the same type of plug (good luck
finding those!) or a piece of soft lead shot just slightly bigger than
the hole. I don't like this because of the abuse of the casting
required to remove the old plug and press or drive the new one in.
What I've had success with is using fuel-proof epoxy to seal around the
edge of the plug. Make everything very clean and dry. A couple thin
layers over all the seams that could be leaking, with a day or 2 cure
time between, should do it. You can test your work prior to reassembly
by (carefully; no spilling) filling the bowl with fuel and let it sit
overnight over a clean white paper. Next day check the paper for drips
and the bottom of the bowl casting for wetness. If all is dry you're
done; if not, clean it all up, start over and do it better. You could
use the same method up front to determine which plug is leaking.
I've done this on 3 Q-Jets over the years. On two the cure worked
completely, on the 3rd the bowl began its draining trick a few months
later, but at an acceptably slow rate. I didn't keep any of these carbs
in service for more than a couple years after rebuilding, so I don't
know how it holds up longer term.
Bill Gray
william.gray@snet.net
-----Original Message-----
From: owner-oletrucks@autox.team.net
[mailto:owner-oletrucks@autox.team.net] On Behalf Of J Forbes
Sent: Wednesday, February 06, 2002 4:17 PM
To: Old Trucks List
Subject: [oletrucks] Quadrajet--carb rebuilding
Like he said, if you have the manual, and some quiet time, it's not bad.
Finding some how-to articles might help, but then they leave out some
steps!
Instead of a bucket of carb cleaner, which is nasty, I suggest using a
spray can or two. That's what I've been doing for the past 5 or 10
years. The kind in the spray can evaporates, so it pollutes the
atmosphere a bit, but it dissipates quickly, instead of hanging around
as a gallon of toxic waste.
Oh, yeah...the thing about how it goes quicker the second time...that's
usually right after you put the rebuilt carb back on the engine and try
to get it to run :) at least that's what happened to me when I did
my first Carter 2bbl at age 13.
Hint--be careful setting the float level, and getting the metering rods
back in! and be sure to read how to take it apart BEFORE you destroy
stuff.
Jim F
59s in AZ
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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