Carb Rant

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oros35
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Carb Rant

Post by oros35 »

So I'm partially venting, partially looking for experienced help.

First thing I did with my 53 was rebuild the carb. Got the midwest military kit, pretty nice kit. Carb was pretty bad, lots of 'mud' in the carb, I don't know how it even ran at all before. Accelerator pump was stuck, everything else was pretty well plugged and dirty. But generally in good shape. The kit changes out just about everything that touches fuel except the float. Did a good cleaning pulling the plugs and all, put it back together and back on the truck.

First try and it fired right up! Ran good but was real rich at idle. Turned the screw in till about a 1/4 turn out and it cleaned up mostly. First question: would a vacuum leak at the wipers contribute to this?

So I took it out for a drive, just around the yard since It doesn't have brakes either. Ran great, Even good enough to spin the wheels in the dry grass! Probably put a mile on it tooling around the yard. Then parked it back in the garage.

Go to start it up a few days later.... and spits, spudders and dead.. Acts like it isn't getting fuel. Mess around with it a bit and -correct- there is pressure to the carb inlet, but only a trickle/drips coming out of the fuel bowl. Thinking what is easy, I put the old needle and seat back in. No change. Looking in the hole the float seems to be down but hard to tell. ---What is it? stuck needle? stuck float? Fuel Pump?

Guess my next step is to take the carb back apart, which I'm really not looking forward to. Anyone have some experience with this that could make it as painless as possible? I just want to drive the dang thing!!!
Last edited by oros35 on Fri Jul 31, 2015 7:16 am, edited 1 time in total.
DCook
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Re: Carb Rant

Post by DCook »

Suggestion is to take the fuel line loose at the carb, and pump the hand pump. if your whole fuel delivery circuit is ok you should get some good fuel flow with each stroke. I would do this before pulling the carb apart. Do you know the how clean the tank and lines are? It may have sucked up enough contamination from your first run to not be able to deliver fuel now.
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1942 Chev. 1 1/2 Ton Dump Truck
1951 M37 W/W, & Field Radio
1953 M43
1958 Navy CJ3B
oros35
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Re: Carb Rant

Post by oros35 »

I will try that. easy enough! thanks!

The rest of the system is an unknown to me, but looks to be newer. There is an inline filter added, and it came with an old pump (maybe the one on it is newer?)

Guess I could pull the filter too, it's just the metal canister inline hose barb type filter. It's been spliced after the fuel pump before the carb.
DCook
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Re: Carb Rant

Post by DCook »

I bought a nice looking 51 truck from a guy in Houston. It was supposta have a clean fuel system, with a liner in the fuel tank. The engine just needed a few stuck valves freed up. What I got was an engine that had been sleeved, and the sleeves were installed wrong. the fuel lines and tank were so full of rust that my fuel level sender had rusted off inside the tank. The liner that had been put in the tank, was all peeling off in big ugly rusty slabs.
You just can not tell what you may have hiding inside a nice looking truck until you get into it!!!
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1942 Chev. 1 1/2 Ton Dump Truck
1951 M37 W/W, & Field Radio
1953 M43
1958 Navy CJ3B
PoW
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Re: Carb Rant

Post by PoW »

It seems the 'new gas' with ethanol really rusts up anything in contact with it like steel. It is really hard on old formula rubber as well.

Fuel tank coatings come in two grades....one will handle new gas, the other not....

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Re: Carb Rant

Post by Carter »

May not be the carb, fuel pump could have failed.
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oros35
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Re: Carb Rant

Post by oros35 »

Ok so pulled off the fuel line, 2 pumps of the primer lever and I had a ton of fuel coming out. Put it back on and pumped the lever again. Could hear fuel going into the carb.

Tried to start it and got nothing, not even an attempt to start. That is new.
Shot some ether in the intake and nothing, not even a pop.

So now I'm leaning toward the ignition system. The ignition switch was left on for a little while by accident. It's a hot wire from the batteries to a toggle switch to the distributor. The condition/age of the points and condensor is also unknown. I do see that the one screw where the condensor goes looks to have the head stripped off. Tried some sand paper on the points with no luck. I am getting 24V at one side of the coil. Didn't check the ohms cause I didn't have a good tester. Will do that next time I'm messin with it.

Pretty sure I should just replace the points/condensor. Thinking upgrading to the Pertronix electronic system. I never seem to have good luck with points on my tractors, especially import junk.
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