carb problems

jifop

New member
hey guys, after months of my van being off the road i finally fixed my brakes only on the first weekend of use to get problems, its a 240cu straight 6

it feels like its an air leak but that aside i noticed while starting the engine that every time i move the accelerator a small jet of fuel squirts out of the side of the carb all over the engine, i have taken a photo of it below, basically where the red arrow points you can see a brass fitting and that is where it comes out.

also i noticed after revving for a while (when it wouldn't start) that a load of fuel poured out of the other pipe marked with the blue arrow all over the exhaust manifold!

so i didn't get to the bottom of my problem but I'm guessing this isn't good! has anyone come across this before? are there any other swappable carbs for the 240?

thanks tim

photo-17.jpg
 
Sounds like accelerator pump discharge passage is clogged. For staters, I'd take the top cover off, and spray every orifice with carb cleaner. PROTECT YOUR EYES! :shock:
 
ok thanks, i'll give that a go to start!

out of interest does anyone know where the pipe with the blue arrow should go? it has always been disconnected!

thanks

tim
 
That's some kind of vent. Just how ols is that 240? Do you have the stock air cleaner on? Is there some kind of charcoal canister?
 
If the van has been sitting for awhile the gas in the carb will turn to varnish and plug up everything. I think your needle valve is letting fuel pass it and that is why your getting fuel coming out of the over flow. the other leak is an odd one as I don't think I have ever come across any kind of bypass for the accelerator pump but who knows. As suggested just take the top off and be careful to try and not tear the gasket. I use a utility knife to try and cut the gasket away from the body of the carb. I think your going to find sludge in the bottom of the bowl. If you don't have a compressor get a can of air from a computer store and you can blow out the jets and such make sure there are no ball bearings that you can end up blowing out and not finding them later. I usually keep a rag over the carb just in case.--good luck
 
thanks guys, i took your advice and took the carb apart, no sludge but there was some dirt in the needle valve also an unknown piece of metal rattling round inside, anyways I've blown it out with carb cleaner and a compressor, put it back together and fitted it, to be honest its running better than it ever has before! i haven't connected up the vacuum advance yet so its slightly less powerful than normal but its running sweet!

its still leaking out of that brass bung so as a temporary measure I've used some wurth silicon stuff and I'll see tomorrow if its still leaking, i suspect it has always leaked from here as i have had a petrol smell from the engine bay that I've never managed to trace! i can't see any cracks but i assume the carb is worn and needs repairing or replacing.
 
The silicon is not going to work gas dissolves it. If you can get it clean you could try an epoxy maybe some JB weld. Otherwise you could carefully remove the brass plug and get some lead shot put it in and than peen it over with drift punch. Good luck
 
Hi,that line coming from your bowl(blue arrow) is the bowl vent. On Econolines that was routed overboard,away from the engine box to keep fumes out of the passenger compartment. Cars and trucks just had an open vent with a stopper that moved with the throttle as the carb was not under and in the passenger compartment so no real worry about the fumes. From what I gather, that carb top with the vent line for Econolines is pretty rare so hang on to it if you can...Steve.
 
thanks, the silicon is a fuel resistant bond seal

well i took it out for a run tonight and it's running great but it smells really rich and the cab stinks of petrol when i stop! i wander if i should try and get a replacement carb or not, not that i know what carb i need or where i can get one!

maybe i'll run a line from the vent outside the van just to stop the smell
 
Hi, maybe since you cleaned some passages, the Idle mixture needs to be adjusted again. Try that and the vent tube...Good luck.
 
You might check to see if the float is bad (too heavy) brass one can see fuel seeping out or hear fuel in it when you shake it look for a crack or pin hole drain it and dry solder it up. With the top off check the wet fuel level too sounds like its flooding. Usually that’s the needle and seat, a bad float and or is set to wrong fuel level.
 
right, so i cleaned the bad boy out this weekend and i noticed the fuel filter was boiling over! :roll: therefore i assume over pressuring the carb, i rerouted the fuel line to cool it down a bit and it does seem less juicy, still not quite right but getting there!

thanks for all your help
 
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