dies out at high throttle

[doinworkinvans]

Finally got the ol girl to idle smooth but when you give it more than half throttle on the gas it starts choking itself off??? She purs like a kitten other than that but when you press on the gas something is going on. Im pretty sure its getting plenty of gas. Ive narrowed down to what I think it is...i think it could be the spark plugs and its not firing on all cylinders except when its at low idle and thats why it idles so good. Because as soon as you press on the gas it starts to choke itself. Any ideas here? Something i could be missing?

 

[foxtrk2]

had similar problem with my m37 turned out to be distributor cap one of th eimported ones it was cracked in multiple places replaced ti with nos cap an druns like a dream now foxtrk2

 

[n1bnc]

Check the distributor to see if the advance is working. Otherwise look at the fuel in terms of fuel filter and proper flow rate. Is the carb new or is it a rebuilt unit? What did you do to get you to this point?

 

[doinworkinvans]

It has a new fuel filter in the last 2 months. As for proper flow rate would I adjust that? The carb is a rebuilt one. I had another one sitting around so I tired it yesterday just for kicks and giggles and it didnt do any different (of course im not sure that extra carb is worth anything anyway). It has fresh gas and runs like a dream when at idle so i really have no idea. The only thing ive really done to the engine is take the carb off and rebuild it and put it back on.

 

[n1bnc]

The fuel pump on a carb system is spec'd somewhere in a TM. You can see if it is a dribble or a reasonable amount of fuel by disconnecting the fuel line from the carb, cranking the engine, and see how much comes out into a bucket. If its squirting like mad, you have plenty of fuel. Otherwise at that point you can look for restrictions or something plugging up the works.

Does it backfire at all? Do you have a restriction of air going into the carb? Remove the air filter and run up the engine.

Have you confirmed that the vacuum advance is working okay?

 

[Carter]

Try rechecking the carb float level, should be 5/64". If set incorrectly it could be starving the engine of fuel at high RPM.

http://image58.webshots.com/658/4/87/64/2500487640045927451FAosYa_ph.jpg

 

[M813A1]

Also check the fuel lines from the tank !! A small kink in the fuel would contribute to the loss of power at Full throttle !!

 

[longshot2171]

How easy does the motor start? Is there a difference when it's a cold start or a restart?
Is the choke set correctly? Other than that, if there's fuel, I'd focus on the distributed. Check the coil, points and distributed shaft for excessive wobble.

 

[doinworkinvans]

Thanks for all the suggestions! I'm gonna check all these things and see what comes up ill be keeping up to date on progress.
-Daniel

 

[doinworkinvans]

checked all the simple things like plugs and wires and distributor cap. All appear to be in good shape. Still starts up like a champ and idles great but dies out once again. I also noticed that if you hold the gas pedal in just a little bit it dies out that way as well after about 20 or 30 secs. It will climb just a little but as soon as you give her the gas it starts to choke out. Im pretty much down to either too much fuel or more likely not enough. I think its an equal chance of either one of those.

 

[doinworkinvans]

oh and its a 12volt if that makes any difference

 

[doinworkinvans]

Try rechecking the carb float level, should be 5/64". If set incorrectly it could be starving the engine of fuel at high RPM.

http://image58.webshots.com/658/4/87/64/2500487640045927451FAosYa_ph.jpg

that link did not work...i would like to see it because i have no idea how to do that! Thanks!

 

[doinworkinvans]

Well seems as though a carb rebuild and cleaning was the issue with the dying at high throttle. Still seems to want to choke if you stomp on the gas right away but if you gradually press it she works good. Now it wants to die after idling after about 45 secs to a minute. Im thinking this could just be an adjustment issue??