throttle responce flat spot

[KEV 5 GT]

can anyone explane why when on tick over i put foot to the floor and theres a flat spot and most time it cuts out ? stock jets and 2nd stage drilled to 1.2mm
is it just a carb thing or can i correct this ?

[Andrew Cooke]

how's your pump jet set?

[KEV 5 GT]

wheres that ? probs still standerd as ive not played with it

[Andrew Cooke]

have you read this?

http://www.rtoc.org/boards/showthread.php?t=27381

first thing is to remove the elbow, and look down into the carb. When you open the throttle (engine off) you should get a nice quirt of fuel out of the tube (you might need a torch). If you don't, or it's dribbling out somewhere else you've found your problem.

[KEV 5 GT]

yes i done this the other day and it wasent squirting out very well just a little dribble
does this mean i need to do a full overall or can i fix the prob on its own ?

[Brigsy]

Pull the jet out of the carb body and clean it thoroughly with carb cleaner.

[Andrew Cooke]

also check if the pump arm is seized

[KEV 5 GT]

ok i will have a look 2mo thanks

[KEV 5 GT]

pump arm was not moving as it should found the prob many thanks :agree:

[KEV 5 GT]

well thought id solved the prob but still the same the took the diaphram out looks find it was sticking abit so free it off but still getting flat spot ?

[Trevhib]

Andy wrote: "first thing is to remove the elbow, and look down into the carb. When you open the throttle (engine off) you should get a nice quirt of fuel out of the tube"

Did you do this?

[KEV 5 GT]

yes thats seems ok now

[Trevhib]

air leak around the carb base or similar?

[Markey Mark (BD)]

Sounds like the pump jet arm could do with adjusting

[Trevhib]

:agree: Looks like it was seized originally, then freed off, so perhaps now needs adjustment like you say Mark.

[KEV 5 GT]

how do i ajust pump jet arm

[Trevhib]

have you read this?

http://www.rtoc.org/boards/showthread.php?t=27381


Kev, it's in here.

[KEV 5 GT]

its says in the diagram not to touch / ajust screw on accelerator arm ?

[Trevhib]

Well that would depend on whether yours is in the position it was when it came out of the factory. If it isn't it will probably need adjusting.

I'm not sure where you're looking where it says not to touch it but the diagram in the last post describes exactly what to do to set it correctly, figure 13.9. Assuming I've understood it correctly.

[KEV 5 GT]

trev you lost me now mate lol

[Trevhib]

Well, within the information in the link provided there is a diagram-supported section called 'Accelerator Pump Jet Adjustment' which goes on to describe how to set the 'Accelerator Pump travel.'

:gagged:

[KEV 5 GT]

arhhh i got what you mean now not in thread in last post lol something about a drill bit using to ajust ? hows this done it dont really explane that much ?

[Trevhib]

arhhh i got what you mean now not in the thread, in the last post lol

In my previous post I actually wrote, "the diagram in the last post describes exactly what to do."

If you've seen the diagrams and description (which I think is pretty comprehensive), but still don't know what to do, then I can help you no further mate. :bored: