Solex carb leaks

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Fred Otjen
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Solex carb leaks

#1 Post by Fred Otjen »

The left solex carb is wet at the base. Something must be leaking, is it the needle / seat valve? I have put a new one in already.

Dick Weiss
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Re: Solex carb leaks

#2 Post by Dick Weiss »

Fred,

Review previous messages.

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David Jones
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Re: Solex carb leaks

#3 Post by David Jones »

Fred, if it is wet at the base it is as Dick said, possible that the base of the carb is warped. However if it is otherwise running OK then it could well be that the fuel level is now set wrong as a result of the float valve change or you have a float failure. The float could have sprung a leak and is sitting low allowing the fuel level to be high, and it will spill over and run down inside the throat and out the throttle shaft bore. You do not say what model year car this is but if it has the early fuel tank then is is possible that with a full tank the fuel level can overcome a weak needle valve and leak though if the fuel cock is left on.
I recently had a float failure where the float had expanded sideways on a very hot day and actually stuck on the sides of the float chamber. A rather unusual failure I thought, and of course the car would not run at all well because it was holding the float valve closed. That was probably better than the reverse of course.
Find out where the fuel is coming from and that will give a clue as to what the problem area is.
If I had known I would live this long I would have pushed the envelope a little harder.
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Tim Berardelli
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Re: Solex carb leaks

#4 Post by Tim Berardelli »

Fred,

The check valve, for the acc. pumps, hidden and forgotten behind and above the acc. pump rod is a prime leak spot for Solex carbs. Loose on most of the Solex's I see.

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Fred Otjen
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Re: Solex carb leaks

#5 Post by Fred Otjen »

David, Tim, Dick thanks for the helpful advice. I'll check the bases for being flat and the pump check vale on these split shaft 40 PII-4 carbs.
I also learned from the carb folks we all like in AZ about some other tips like removing those accel pump diffusers below the squirters, not using the new needle valves that don't have the ball bearing, their way to check float level and more very helpful stuff.
Thanks to all, we'll see how things go

Dick Weiss
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Re: Solex carb leaks

#6 Post by Dick Weiss »

The Solex carb float(s) don't have the clearance-to-the-float-bowl problem like the twin floats in Zeniths; Only if the hinge mechanism isn't bent.
A possible leak is the injection assembly on the side of the body and the 6-screws may be needing a "snug-up".

Depending on how long it's been since the last rebuild(?), the 2-diaphrams may need replacing and the needle valve
isn't clogged. After pulling off the top cover(s), make sure the float "floats"; If not, check the weight--see the specs.

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