Super Jet Priming of superjet often, why

[Thomasbv]

Why should i prime my superjet evertime i have turned it off to take a break, before it can start... even if it is for 3-4 min i have to prime it before it can start again ? and when it is running it starts at the first time every time..?? somebody help me..

 

[tor*p*do]

rebuild the carb -
could be a pinhole in the fuel pump diaphram
or a leaking needle and seat

 

[Thomasbv]

Have just rebuiled both carburators, with an oem mikunu rebuild kit..

 

[Matt_E]

Did it have this problem before you rebuilt the carbs?

 

[Thomasbv]

dont ha any idea, because when i bougth it the carbs need a rebuild kit...

 

[sjetrider]

chip reads?

 

[WFO Speedracer]

First come out on the low speed adjusters about 1/2 -3/4 of a turn and see if that helps, if not you may have to change popoff springs for a lower popoff pressure.

 

[munki63]

Needle and seat would be my first guess, does it still need to be primed if you start it and let it idle for a bit then turn it off? Same question again but running wide open?

 

[RoTAxGreNade]

Use a pop off gauge and pump it up somewhere below where it pops to see if it holds pressure - 9 out of 10 times it's the needle/seat not holding pressure.
After that it's all in the low screw adjustments

 

[Thomasbv]

Thanks.. will order seats and needles..
but 1.2 1.5 2.0 2.3 or 2.5 mm ?

Protec pipe - atp snake head.

 

[Superunatural]

Thanks.. will order seats and needles..
but 1.2 1.5 2.0 2.3 or 2.5 mm ?

Protec pipe - atp snake head.

Did you replace them when you rebuilt? What was in there before? I ordered a few different ones so I could play with pop off pressures.

 

[DangerBoy]

First come out on the low speed adjusters about 1/2 -3/4 of a turn and see if that helps, if not you may have to change popoff springs for a lower popoff pressure.

X2
try this 1st

 

[Dustin Mustangs]

A leaky needle and seat would not cause this. An improperly sized one could.

 

[Sospikey]

Erhmm, what about a leaky one-way tank valve? Worth checking imo.

 

[easyrhino]

See any fuel linking around the primmer pump? Fuel pump could be pulling air thru the primmer pump depending where the fuel line is "t"-ed.

 

[aramis]

I had the same problem once, and pulled my hair out trying to find it. It was a small nick in one of the primer lines, allowing air to deprime the main fuel line...check that and the primer itself to see if it's leaking any air.

 

[munki63]

Double check your fuel filters as well