So i ve been working on my x2 lately and today i pulled the carb off to see what high and low jets i had in the carb.... after talking to carb apart and putting it back together i decided to start it up... upon starting it, it went full rev with out hitting the throttle.... My first thought was no big deal just hit the stop button... when i hit the stop button several times it was still at full throttle and didnt want to shut off... luckily i freaked out and yanked the fuel line off and it shut down seconds later.... needless to say i have some trouble shooting to do now.... But id have to say i was worried the motor was going to blow...
650/X-2 Scary!!!
- Thread starter blown
- Start date
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
It was too lean.
Wilke
X2 stole my life
- Location
- Indialantic, FL
Its called dieseling, and its cause the engine is too lean and/or there is an air leak somewhere. check the carb base gasket, clean the carb, do a leakdown test, check the carb settings.
Next time dont pull the fuel line. Pulling the fuel line risks giving it a lean siezure. If it happens again, pull the throttle wide open and hit the kill switch (sounds counter-intuitive, but it works ; the extra air cools the cylinder and stops the fuel from burning without spark), or spray a bunch of fuel into the carb to flood it out.
Next time dont pull the fuel line. Pulling the fuel line risks giving it a lean siezure. If it happens again, pull the throttle wide open and hit the kill switch (sounds counter-intuitive, but it works ; the extra air cools the cylinder and stops the fuel from burning without spark), or spray a bunch of fuel into the carb to flood it out.
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Looks like It was an air leak from the carb base gasket... I order a rebuild kit for the carb to be on the safe side.... I need help with the high and low jets though.... any ideas of what i should start with for a stock motor with a 44mm mikuni, Jetsport intake, and boysen reeds?
- Location
- Philadelphia
def an air leak happened to my buddy awhile ago
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
My stock 650 with a 44 mikuni was 150 120
- Location
- Dallas, PA
150 hi
120 lo
2.0 n/s
0.80g spring
1-1/4 turn out on top
1 turn out on bottom
120 lo
2.0 n/s
0.80g spring
1-1/4 turn out on top
1 turn out on bottom
Wilke
X2 stole my life
- Location
- Indialantic, FL
I've done it with some rubber gasket sheet from autozone. I layed it over the carb base and used an xacto knife to cut it out. Worked well, but I went back to RTV when it wore out and I didn't have any more material handy.
- Location
- Dallas, PA
There is no need to use RTV on the fiber intake gaskets. A better option would be to buy yourself a can of copper gasket spray if you feel the need to use something on the gasket.
Fro Diesel
creative control
- Location
- Kzoo
The chamber you put on your exhaust pipe does not create an intake leak.
Not sealing matting surfaces properly or using rtv... bad jojo. I reuse a jetmaniac carb gasket all season no issues. Age kills gaskets.
sent from Fro Diesel using tapatalk.
- Location
- Ontario CA
My 650 did this right after I re-built it, started it and it went to the rev limiter and the kill switch didn't work so i yanked the plug boots and it kept doing. I yelled "my engine's is gonna blow", my wife ran away like it was a bomb (still makes me laugh). It ended up being some build up clogging the fuel filter i had on it. My engine is 100% re-built with all new gaskets crank everything, since ditching the fuel filter it has never happened again.
I rebuilt my 650 completely and took it out for first time 2 days ago. At home starting it it did this, though hitting the stop button was fine. I was convinced it was an air leak, tore the carb down, retorqued and applied gasket sealant to everything, checked throttle shaft, etc. etc. Finally my dad looked at it and said just to turn the screws all the way in, it revved like this once more, than wouldn't start like expected. Slowly increased screws until it'd start, then took it to the lake. Turned out to be SOUNDING like it was running away when under no load, and I had the idle speed a little too high and once retuned it was fine. Still sounds like it's revving like mad when sitting on the trailer, but in the water it's fine.
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