Carb question?

topchop

Senior Member
'47 V8, single Model 59 carburetor.
After sitting more than a week, fuel bowl empty.
Have to add add a 1/2 cup of fuel in carburetor to start.
I know this is not normal. Could it be evaporating? Car is in attached garage and no sign of fumes and nothing on intake near carb.

Normal otherwise, runs great, and if started within a week, no problem.

Ideas? Comments?

Thanks
 
TC,
A lot of it is evap but mostly it is your fuel pump will not self prime. The repop
pumps that the big guys sell work great for a while but then the 'rubber' valves give up.The old fiber valves seem to handle the alcohol fuel quite well and if done right will
self prime the pump but to be sure take more cranks. The Shewman check valve
flex hoses really work to help self priming but the fuel must be clean.
Charlie ny
 
Your power valve is bad. Very common problem, it is letting your bowl leak down. Swap it out.
 
To check the power valve, you need to remove the carb, fill the bowl and watch to see if anything leaks out. As Charlie said, it is probably evaporation.
 
I use an electric pump (the old click click click SU type) to prime the carb then run off the mech pump. It saves a lot of cranking.

I suppose if the mech pump failed the elec pump would get me home. Never had that situation yet, though (touch wood).

Mart
 
I vote for evaporation. Does it on my 38 Deluxe and my 57 w/3X2 intake on it. Mine sit for weeks at a time without starting. If I start them up every few days no problem.
 
So when these cars were new they would not start after a week? No way, his carb is leaking down somewhere, it is not evaporating that fast.
 
I'm with you VANSPEED and I would also submit that there is a loose fitting somewhere in the system that is allowing the fuel to gravity back to the gas tank as well!!! Go from tank to carb and double check ALL connections to make sure they are ALL TIGHT!!!! And see if you have a station in your area that sells Ethanol FREE gas too!!!
 
It's got nothing to do with when they were new. Fuel today is formulated differently, which causes rapid evaporation. Residual underhood heatsoak after shutdown is the main cause of this evaporation. This is not to say that a leak has not also developed, particularly as today's fuel tends to destroy gaskets and rubber.
 
Hi, just finished rebuilding banjo rear end

Ref thread http://www.fordbarn.com/forum/showthread.php?t=190279

Now I am at the point of returning to this thread to work on the hard starting.
Reference flatjack9's post (#4) I want to see if I have a power valve leak.
Tonight I drove the car into the garage and removed the carb top and measured the fuel level, which is exactly 1" below the flange.

For reference, can anyone tell me if this is the correct level for a proper running carb?

Thanks
 
I think the first and easiest check is to take the carb off. Take the top off and fill the bowl, Set it on a newspaper and see in the morning if the paper is wet. If it is, I suspect the power valve is leaking. If so, get a new one from CharlieNY.. He machines the gasket surface for a good fit. JMO
John
 
oldford2, I didn't have to pull the carb as you suggested. 18 hours after I pulled the carb top off, observed the fuel level in the bowl down 1/2". (I had placed a flat metal plate over the bowl opening to minimize evaporation). Looks like the PV and/or gasket leaking. Calling CharlieNY!
 
So when these cars were new they would not start after a week? No way, his carb is leaking down somewhere, it is not evaporating that fast.



When these cars were new, there was no alcohol in the fuel either.
Still don't think it will evaporate in a week though.

Sal
 
Sal, I've seemingly eliminated a lot of carb issues, once I quit using ethanol fuel. One of them seems to be that I can leave the car sit for weeks and then go out and start it with minimal cranking, two pumps of the accelerator, and a pull on the choke.

Granted I have sorted out all carb (switch to a 97), pump, and ignition issues. Maybe I'm just a little superstitious now. :)
 
I think this power valve leak down is the part cause of hard starting hot or cold ,(confused with Vapour lock) .Holly or Ford.Hot you get a flooded engine cold there's no fuel for a quick start ,Like Tinker I have a instant start after three weeks sitting ,that's a Stromberg .The new power valves sold maybe faulty and they leak direct into the manifold through the PV vacuum runners .Ted
 
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