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jonpaul03

My 78 BRAT project....

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Well man, it's pretty hard to get an idea from your descriptions, but I think first you need to check if you have power at the fuel pump.

You will have to do this with a test light or voltmeter across the two fuel pump wires where they connect to the pump. 

You will have to crank the engine over while looking at the light or meter for voltage. 

If you DO have power, then something is wrong with your pump, or the lines/tank is clogged.

If you don't have power, then you need to look to the voltage regulator and alternator. If either of them are not functioning properly, you will not get power to the pump.

You can also provide temporary jumper wires to the pump to see if it will run. You should be able to hear it clicking, and it will pump gas into your bucket if the fuel lines and tank are clear.

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Pump works fine when directly connected to the battery. I have continuity b/w the pump and the VR. The alternator tested good at Autozone. I havent been able to check the power going to the pump with cranking the engine. I have bypassed the tank with fuel cans.......and still same result. The pump isnt pumping. Is there a fusable link or something I should check? From what I have read the pump gets its power from the VR....and the VR gets its power directly from the Alternator. Not sure what the issue is.

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So..... I have continuity between all associated components and I still do not get power to my fuel pump. I have replaced the Voltage Regulator and pump itself. The generator tested good and I replaced the points/condenser. Battery is good and all fuses replaced as well. I currently have 2 pumps hooked up to test different grounds and still nothing. I bypassed the fuel tank and ran the fuel line to a gas can....still nothing. Any ideas?????? Has anyone ever seen a resistor block go bad? It is the only thing within the circuit I havent tested or replaced.

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Has anyone eliminated the Vapor Separators on each side of the fuel tank or bypassed them at all? not sure, but could be the reason for my NOT starting/running issue I currently have. I am running out of options. Any help is greatly appreciated!! 

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Got her running....anyone with a Weber 32/36....what did your mixture and throttle adjustments end up at? 

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I also have a 1978 gen 1 brat

owned since it was new in 1978

and have enjoyed it thru the years, it's bullet proof.

the issue you are having with the starting seems the be part and parcel of the weber carb design

I started having the problem when I replaced the original Hitachi carb (tended to develop vacuum leaks.

Replaced it with the same carb you have i still have the elect chock on it  though.

Had to finally get it adjusted but a mech who has the old emissions testing (tail pipe)equip.

Runs great since then, except when I let it sit too long and it's cold.

Then I have to use either and spray the carb to get it to start.

 As long as I do not let it set for more than 2-3 weeks it starts right up in the morning.

I also have recently added an AC system (needed here in Tucson)

I have had wiring issues  since installing it but getting it worked out.

 Had you made sure that you do not have some of the original brat wiring connectors hooked up (do not need or want) the wire for the anti dieseling switch tied to anything And hopefully you have the vacuum line fittings that are not needed with the Weber carb sealed off. 

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Did you get the fuel issues worked out?

I added a second fuel pump and the vapor system from my 1982 donor brat.

It included the vapor separators to get the weber carb to play with the rest of the system.

The only issue I have now is sometimes it runs rich so have added a switch to shut off the forward engine compartment fuel pump. 

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My float valve was stuck and timing is off. I can get it to run with throttle applied, but it still wont idle.

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I am looking for a good way to hook up the vacuum lines in my BRAT after the Weber conversion.

 

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