Page 1 of 1

Dragster only idles on choke.

Posted: Sat Jan 04, 2014 11:21 am
by Bufficus
My rarely used Dragster has developed a problem where it will only idle with the choke on even when warm. Once off the idle circuit it runs fine.

It has a flip choke conversion on a standard PHVB 20.5 carb, which until now has been faultless.

I assumed it was a blocked pilot jet, but have stripped and cleaned the carb twice, but the problem persists. The reeds appear to be fine.

Am I missing something obvious?

Re: Dragster only idles on choke.

Posted: Sat Jan 04, 2014 11:34 am
by Rich_T
Could be an air leak, old fuel?

Re: Dragster only idles on choke.

Posted: Sun Jan 05, 2014 10:01 pm
by Bufficus
Thanks for the input Rich.

It has new fuel and no obvious signs of an air leak.

I had another little play today and it seems it won't run at all without the choke.
It hasn't got hot enough for me to suspect it may be electrical, besides I have tried a different CDI and it's the same.

I was wondering if it could be some kind of fuel starvation issue. Although it seems to flow ok if the pipe is removed from the carb. :?

Does anybody know how the automatic fuel tap works on a dragster or how to remove it?

Re: Dragster only idles on choke.

Posted: Mon Jan 20, 2014 9:21 pm
by ferritt
works on vacuum i believe, think psn it batley do a manual replacement tap

Re: Dragster only idles on choke.

Posted: Mon Jan 20, 2014 11:28 pm
by Bufficus
Thanks I'll give them a call.