1957 Big Twin 35 WONT START

[devilsriverlamb]

I finally got done replacing some needed parts on my motor and went to try and start it last night. Unfortunately it won't start, it just cranks and cranks. Does anyone have an idea on what to try. Thank you for any help

 

[devilsriverlamb]

Re: 1957 Big Twin 35 WONT START

well I think I have figured out the problem? I am getting a spark but no fuel. I am not getting a vaccuum on my gas tank and therefore I am getting no fuel to the motor. does anyone know what would cause there to be no vaccuum?

 

[tashasdaddy]

Re: 1957 Big Twin 35 WONT START

your motor requires a 2 line gas tank, unless you have converted it to fuel pump.

 

[devilsriverlamb]

Re: 1957 Big Twin 35 WONT START

I have a two line gas tank on it

 

[lindy46]

Re: 1957 Big Twin 35 WONT START

It's a pressure tank - pressure from the engine pushes gas out of the tank to the carb. No fuel pump. The gas cap must be tight so pressure builds up to keep the engine running. Pump the primer button to start. If it still won't start, spray some pre-mixed gas/oil into the carb and see if she fires. If you can get it started but it quits, try pushing the primer button on the tank and see if it keeps running. If it does, then you have a pressure leak either in the tank or the air line going to the tank.

 

[rolmops]

Re: 1957 Big Twin 35 WONT START

well I think I have figured out the problem? I am getting a spark but no fuel. I am not getting a vaccuum on my gas tank and therefore I am getting no fuel to the motor. does anyone know what would cause there to be no vaccuum?

The primer pump on the tank does not pressurize the tank. It sends fuel to the carburetor,which will start the engine.Only then will you start building up pressure in your tank.
Pull your line off the connectors.First the fuel line one and see if the fuel comes out the end of the hose when you prime the line.If not, your problem is on the tank end.If fuel comes out,your problem is dirt in the quick connectors.Clean them and try again.If that is ok check the filter in the fuel bowl you may remove it altogether.These old girls often work better without that filter.Last of all check if there is a kink in your fuel line from the bowl to the carb.
Good luck!!

 

[tashasdaddy]

Re: 1957 Big Twin 35 WONT START

does the tank need a rebuild kit? easy to do.

 

[devilsriverlamb]

Re: 1957 Big Twin 35 WONT START

OK I got the tank to start shooting fuel! I didn't realize that it needed to be primed up( boats are foreign to me) Now that I am getting fuel to the carburater it will start and die immediately. Any ideas

 

[rolmops]

Re: 1957 Big Twin 35 WONT START

OK I got the tank to start shooting fuel! I didn't realize that it needed to be primed up( boats are foreign to me) Now that I am getting fuel to the carburater it will start and die immediately. Any ideas

When you prime the carburetor,make sure that you fill the glass bowl on the side of the engine (take the cover off and follow the fuel line you will find a glass bowl)make sure that there is no fuel leak there.Keep on priming until you feel some serious resistance.That means that the glass bowl is full and the fuel reservoir in the carburetor is also full.Now start again and see what happens.Make sure that the cap on the fuel tank is shut tight.

 

[devilsriverlamb]

Re: 1957 Big Twin 35 WONT START

Ok here is where I am at now. I have primed until the bowl is completely full and the carburator reservoir is full, I have no leaks on the fuel hose. It will not start unless I put gas/oil directly in the carburator, but will only run about 2-7 seconds

 

[lindy46]

Re: 1957 Big Twin 35 WONT START

As I said earlier, you have an air leak somewhere, and the tank is not properly pressurizing. Is the gas cap on securely? If you remove the gas cap after the motor runs a bit, does air escape from the tank? It should make a whooshing/hissing sound when you remove the gas cap.

 

[tmcalavy]

Re: 1957 Big Twin 35 WONT START

It's not getting fuel from the carb...check your high and low speed needle settings: 3/4 turn out (c-clockwise) for high speed and 1.5 turns out for the low speed, adjust from there to find the sweet spot for both then tighten down the lock nuts.