Advice needed: Ford 94 carb hesitation problem

COE Dan

COE Dan

Senior Member
Ford Barners,

I recently rebuilt my Ford 94 carb on my '39 Deluxe. Carb worked fine before but leaked badly. Full cleaning, all new gaskets and internal parts where necessary for the rebuild.

After rebuild, I still get fuel seeping out the right side throttle shaft (shaft is worn) and fuel leaks past the threads and out the back of both mixture screws. I had new mixture screws with the kit but I couldn't use them. Turning both in all the way to the stop didn't shut off fuel and the engine kept running at idle so I put the old ones back in which do stall out the engine if turned in all the way.

Also, I occasionally note fuel reside on top of the carb that has escaped the vent just below the air horn opening...it's kinda like it burps gas but I don't know how often or whether this is connected to the following issue.

Now here's my issue:

After the engine is warm and I've shut it off for 10-20 minutes then attempt a restart, the engine starts fine at idle. However, as soon as the throttle is opened, the engine stumbles and hiccups until you let the throttle close to the idle position. This occurs for about 3-4 minutes. I'll gingerly adjust the throttle position till the problem clears itself. After I clear the problem, the carb works fine during the remainder of operation and the car drives fine.

I've got a few ideas but I'm not a carb expert. This was my first attempt at a 94 rebuild so I'm looking for some seasoned advice to validate my ideas. Thanks.

COE Dan
 
COE,
Try a float setting of 1 3/8 from the air horn gasket face to the top of
the float with the air horn inverted. Do you know for sure that your fuel pump is
operating in the 2 1/2 to 3 1/2 psi range. I can assure you that if you are using
the kit supplied power valve ( usually 7.5 in / hg ) it is supplying too much fuel
under demand conditions. The motor should stall or stumble seriously long before
the idle screws are turned in all the way.....this the primo indication of a leaky
power valve. The leak may be caused by a vacuum leak between the iron base and
the bottom of the bowl or just a faulty PV. Just because the PV is new it don't mean
it's good.
Charlie ny
 
Where did you get your rebuild kit? Depending on where your kit came from the parts may be junk. I got mine from Ken from CT and the parts were top of the line and everything work as it should. If the gaskets and not correct your will have leaks. Quality parts means a happy camper when you are done.
 
Depends where you got the kit from,most are overseas ones and contain some wrong and incorrect parts in them EI: rubber tipped needle inlet,rummer accel pump wrong power valve. Charlie has the good stuff also,you wont go wrong dealing with him if you choose. ken ct. The worst of the inlet needles are the ones you tighten with a small wrench 3/8" i believe. Their the pits .
 
COE Dan said:
After the engine is warm and I've shut it off for 10-20 minutes then attempt a restart, the engine starts fine at idle. However, as soon as the throttle is opened, the engine stumbles and hiccups until you let the throttle close to the idle position. This occurs for about 3-4 minutes. I'll gingerly adjust the throttle position till the problem clears itself. After I clear the problem, the carb works fine during the remainder of operation and the car drives fine.


COE Dan
Click to expand...

Mine leaked a bit due to dirt in the float valve. Occasionally the engine would go rich and flood. Not exactly sure if this is your issue or not. I have multiple filters now. And a new fuel tank is in the future. I cleaned mine pretty good but it doesn't take much dirt to cause a problem.
 
You must log in or register to reply here.
Back
Top