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Carb problem?

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mylillooker

mylillooker

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I've got a 79 Midget w/a Weber carburetor. I've just recently swapped engines. The carb in the car now is the same one that I was using before.

The problem is that when I start the car the engine revs way up and the dies right out in a matter of seconds. Trying to give it more gas doesn't help. It still dies right out.

We've taken it apart enough to check the float bowl and unscrew and clean the jets, but that hasn't helped the issue.

NOW, if we hold the choke plate closed it does continue to run, but at an incredibly high idle!!!!

When I took the carb off the old engine, I didn't take it off the manifold. I didn't mess w/it at all. It did sit for a couple of months before I was able to put it all back together.

Any ideas as to what it might be? Any questions that could help you diagnose it? Anything...? It seems as though it should be something simple, but what? /ubbthreads/images/graemlins/confused.gif Please don't assume anything, I'm very new to this DIY mechanic stuff.

Winter's here and the bicycle I've been riding ain't cuttin' it anymore!! /ubbthreads/images/graemlins/crazy.gif I need Help!! I need a car and fast!

Thanks,
Mario the auto mechanics idiot!
 
Possible air leak or fuel delivery. You could start at tank and eliminate everything to carb, since you have been in to it already. Make sure fuel flows well to carb, including filter. You may need to soak or spray all internal fuel passages in carb to make sure all is clear. There are some passages that can easy be restricted causing problem. Check for air leaks around all gaskets and hoses. Blockoff or bypass all vacuum lines on carb or manifold. Its probably something obvious, just need to eliminate all other avenues to get there. Process of elimination from fuel tank to carb, one at a time.
 
Thanks Terry! I read what you're telling me, but again... I'm new to this.

So to clarify, I get under the car and check the line from the fuel tank all the way up to the fuel pump and from the pump to the carb for leaks? Now am I looking for fuel actually dripping from somewhere? And vacuum leaks? How will I know those? Will I hear the air as the engine runs?

When we took the carb apart there was fuel in the float bowl. Does this mean the pump is o.k.? There’s enough fuel to start it w/o my foot on the pedal, it dies out.

You said soak or spray internal passages, I have a carb dip solvent in a bucket that I purchased. How much will I need to take apart to dip it and will this mean new gaskets? Where can I purchase gasket for this weber carb? Will spraying it have the same effect?
Thanks for your much needed help!

Mario the auto mechanics idiot /ubbthreads/images/graemlins/crazy.gif
 
I am going to go out on a limb here and say it sounds like your problem could be a massive vaccum leak. Make sure all your vacuum lines and hose are connected where they should be and that there are no cracks etc. in the hoses. If you don't find anything, start the car and keep it running using the technique you described above. While the car is running, spray WD40 or some other aerosal on the manifold gasket and where the carb meets the manifold. If the engine stumbles or accelerates, you have found your leak. I am GUESSING you have a BAD manifold gasket leak.
 
Thanks! I won't be able to get back to it til tomorrow, (Wed.) but keep the info coming. I want to try everything before I admit defeat and call a professional. Aurgh! I'll keep you posted. You guys are great!!
Mario the auto mechanics idiot!
 
Professional? You are now the professional. By order of the board. heh.
 
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