Yamaha 2001 XLT PV Will not idle

[leepat60]

I bought this ski with 100 hours, compression same at 125. Could not get it to idle and bogged down/died when wot. Installed D-plate, mixed gas, fuel primer, rebuilt carbs (60 pop off), drained gas tank to verify it was clean and new filter. With all this the only way it will stay at idle is with a squirt of gas from the primer every approx 15 seconds. I ran a clear gas hose directly from the tank to the carb rack. The carbs suck it in just fine and fuel stays in tubing for awhile after shutdown- still the same idle problem. Tank vent check valve is ok. Thinking I made a carb rebuild mistake, I have torn the carbs down and everything is in its proper position. The booster pump is clean, diaphragm looks new, but does not pump gas (manually on bench). I’m wondering if I block off the fuel inlet at the rack, install a brass tee on inlets between carbs and run tubings (2) directly to tank outlet and reserve fittings if that will work. I need some ideas before putting this thing back together and what to do about booster pump. Thanks

[Technical Support]

Re: Yamaha 2001 XLT PV Will not idle

The accelerator pump will not prevent it from idling, so that's not the idle issue. Did you replace the needle and seats?

[leepat60]

Re: Yamaha 2001 XLT PV Will not idle

Needle and seats looked ok after removing, spraying with carb cleaner and air. When doing pop off (set at 60) needle held when backed off to 40-50. Is this the "last" resort based on what I've done so far?

[Technical Support]

Re: Yamaha 2001 XLT PV Will not idle

I would go through the carbs 1 more time, I dont know what you have done so back track and see if you find anything.

[leepat60]

Re: Yamaha 2001 XLT PV Will not idle

Thanks for your thoughts. Do you think this is definitely a carb problem? Can I assume the other checks and changes described in my original post are ok?

[leepat60]

Re: Yamaha 2001 XLT PV Will not idle

One more point-- I just found an old post where on a 2001 xlt pv, the idle could not be adjusted. Poster found the low speed screws had been screwed in all the way. Should I go ahead and remove plugs for hi and lo speed screws?

[Technical Support]

Re: Yamaha 2001 XLT PV Will not idle

You could but if that is what it takes to make it idle then you still have problems because the screw controls fuel delivery and closing it off is cutting back fuel and that's going to cause lean problems.

[leepat60]

Re: Yamaha 2001 XLT PV Will not idle

Perhaps I did not explain myself clearly enough. In the old post I referred to, the new ski owner of a used 2001 PV could not get his to idle after rebuilding the carbs. When he drilled out the plugs hiding the low and high speed screws he discovered the low speed was screwed in all the way. He said he adjusted the low to factory specs and it worked just fine. Mine will not idle on its own unless I use the primer to squirt a little gas. Could this indicate a bad adjustment of my low speed screw? I feel certain the carbs are clean and parts replaced in proper position. I really hate to drill the plugs out unless necessary. thanks again----

[Technical Support]

Re: Yamaha 2001 XLT PV Will not idle

Well you will not know what the low screws are set to unless you remove the plugs. They should be at 1-1/8 out.