2000 sx150 OX66.
Starts quickly when cold, runs for 30 seconds than starts to stutter. Idle goes low and motor will shutter and then stall. Starts right up and if I up the revs for about a minute it idles OK. When I cast off, the motor may shutter for another 30 seconds or so as I get up to speed. Then is all clears up and runs perfectly all day. This started last year. Everything has been checked that I can check, new plugs, filters, O2 checked and cleaned, VST checked ( clean to start with), throttle adjusted etc.
If the motor were carbed (it isn't of course) I would suspect a bad choke since it runs fine after warming up. I haven't pulled the low pressure pumps yet but they are not that old and I don't see or smell anything that would lead me to think the diaphragms were leaking but I suppose I will have to bite the bullet and check them.
Update: 7/19
The temp sensors and thermal switch both tested good.
I started the motor and it started right up but after about 20 seconds, it started to slow and stutter. I pumped the primer bulb. It wasn't soft and it made no difference, the motor stalled after idling low.
I pulled one low pressure pump and while looking at the underside, pumped the primer. No fuel came out of the diaphragm but fuel did leak out of the seam where the cover bolts to the housing. I bolted the unit back on and took a look at the screw that holds the cover on. It was quite loose which explains the fuel leakage when the pump was unbolted. There was no fuel leakage when I first pumped the primer with the unit bolted to the powerhead.
I didn't test the second pump since I have to swing the VST out of the way to get to it. I am not convinced that my idle and stutter issue id LP pumps.
Anyone have and insight into this issue.
Thanks
Starts quickly when cold, runs for 30 seconds than starts to stutter. Idle goes low and motor will shutter and then stall. Starts right up and if I up the revs for about a minute it idles OK. When I cast off, the motor may shutter for another 30 seconds or so as I get up to speed. Then is all clears up and runs perfectly all day. This started last year. Everything has been checked that I can check, new plugs, filters, O2 checked and cleaned, VST checked ( clean to start with), throttle adjusted etc.
If the motor were carbed (it isn't of course) I would suspect a bad choke since it runs fine after warming up. I haven't pulled the low pressure pumps yet but they are not that old and I don't see or smell anything that would lead me to think the diaphragms were leaking but I suppose I will have to bite the bullet and check them.
Update: 7/19
The temp sensors and thermal switch both tested good.
I started the motor and it started right up but after about 20 seconds, it started to slow and stutter. I pumped the primer bulb. It wasn't soft and it made no difference, the motor stalled after idling low.
I pulled one low pressure pump and while looking at the underside, pumped the primer. No fuel came out of the diaphragm but fuel did leak out of the seam where the cover bolts to the housing. I bolted the unit back on and took a look at the screw that holds the cover on. It was quite loose which explains the fuel leakage when the pump was unbolted. There was no fuel leakage when I first pumped the primer with the unit bolted to the powerhead.
I didn't test the second pump since I have to swing the VST out of the way to get to it. I am not convinced that my idle and stutter issue id LP pumps.
Anyone have and insight into this issue.
Thanks