Mikuni TM-36 Pumper Carb Question

[jcane88]

Hey everyone,

 

I have an xr400 that I cannot start after getting a the mikuni Pumper from XRs only. I have a ProCircuit T4 pipe on it, and just had my top end rebuilt with new piston. Valves and timing are tuned to spec. I have tested pilot jest from 15-45 with no luck. After taking off the carb I found that there was a jest missing in the intake side of the carb..does anyone know if this could cause starting and running issues?

[JoeRC51]

There's not supposed to be one in the left hole. Do you have spark ? Do you smell gas after kicking a few times ?

[natey]

good luck with getting help from xrs only based on my nightmare experiences with them. You can read about my story here......https://thumpertalk.com/forums/topic/1188775-new-mikuni-42mm-pumper-problem/

mikuni oz may be able to help you in terms of set up and you may be able to download a free carb manual thru Mikuni. My pump nozzle was way big(50 and should have been 30) and as soon as I got that right, the SOB started right up. 

 

[jcane88]

Thanks for your feed back on this@natey Where do I access the pump needle to see the size? From the top or bottom opening?

[jcane88]

@joeRC51 I checked and had spark, also installed new plug. I don't think I've smelled gas when kicking it. I know I have fuel flow from the tank line into the carb and In the carb.

[natey]

11 hours ago, jcane88 said:

Thanks for your feed back on this@natey Where do I access the pump needle to see the size? From the top or bottom opening?

Pump nozzle access from bottom, then it later has to adjusted from the throat of the carb so that it is spraying at the needle.

[ericsXr600R]

Try turning the idle up a bit. It can help get it going so you can fine tune it.

[xrjones]

would it help to squirt some fuel or either into intake to see if it will fire alternatively?

[Schrauberklaus]

I'm not 100% sure , but is there normaly not a closed plug in that second thread at the TM36?

Spare part catalog call it Part 39 ,main Air Jet

Try temporary to close it with a plastic plug and if it start you know what you need to order .