951 low idle speed

[tommyadrian5]

After having bill rebuild my carbs w/his rejet kit and fly filters i finally got the boat back together. I hooked it up to the hose in my driveway and cranked it up, it started right up, but i couldn't get it to idle at more than 1300 rpm to save my life(out of the water, where it should be around 3000), it was a very rough low idle, vibrating violently on the rubber motor mounts. The idle screw is all the way in, new plugs, fresh gas. If i gave it gas it would roughly rev up until smoothing out at the higher rpms. The boat ran fine before the carb rebuild, i did it more as a precaution as i broke a rod in my old engine. I played around with the low speed screws with no effect, changed the calibration on the oil pump (more oil to less oil) with no effect. Any ideas what could be wrong.

[ August 04, 2003, 09:04 AM: Message edited by: tommyadrian5 ]

[Bill O'Neal]

If you cannnot get it to run correctly, return the carbs to me at my expense, I will go back through them. I do not know why it would act like that, unless I screwed something up inside the carbs?
Call me at 626 914 9509.

[Bill O'Neal]

BTW, did you try adjusting the tee handled idle adjuster screw to speed up the idle to around 2800 rpm when out of the water?

[tommyadrian5]

I think i might have found my problem, when i pulled my carbs off last night, i noticed that one of the small lines(3 or 4 mm) which seem to run to the small thin injectors on the outside of the choke plates had gotten pinched by the mounting bolt. I couldn't tell if it had punctured the line but i did remember noticing an air bubble in the line while i was running the boat out of the water. Is this a low speed operation sensitive fuel (injection) line, in other words, if this was punctured, would my boat run on only one cylinder, causing my low and rough idle?

[ August 05, 2003, 09:07 AM: Message edited by: tommyadrian5 ]

[Bill O'Neal]

Yes, when you pinch the fuel line, it will stumble on accelleration. But, it still should idle correctly. Also, usually, when the hose is pinched it will cut a hole in the line. You can replace that line with a short piece of plastic primer line.

The description that you give is similiar to how a motor runs when the throttle linkage has fallen off that connects the two carbs together.

[ August 05, 2003, 09:13 AM: Message edited by: Bill O'Neal ]

[tommyadrian5]

So should i bother replacing this hose and putting them back on the boat or send them back to you, do you think the hole in this hose is causing the idle problem or do you think it is something else?

[Colin GSXL]

That line sounds like the accelerator pump line from your description. I would guess an air leak in that would make the motor run faster not slower. There would be no gas in this line until you had pumped the throttle a few times so that may explain the air bubble.
Are these lines clear on your ski or have they been replaced as mine is grey? It's not an oil injection line to the manifold?

[tommyadrian5]

No its not an oil injection line, its a line, on the carb(it begins and ends on the carb). It has been replaced, by bill when he rebuilt the carbs. Its normally grey i believe, but still smaller than the regular fuel hoses. It seems to run from an outlet near the main fuel line, then splits, then the split hoses go up to an inlet fitting on the carbs, which seem to go to a type of injector on that airbox side of the choke plate(it runs through the carb body to a nozzle inside the carb tunnel). What is this injector, it sticks about a cm into the carb tunnel, but on the airbox side of the choke plate?

The air bubble in this hose that has the hole in it remained even after i revved it up a bit.

Does anybody know what hose this is?

[ August 05, 2003, 01:02 PM: Message edited by: tommyadrian5 ]