Carb Problem?

[jeffc]

I bought a used 1998 XL1200. We test drove it and it was great except for a hesitation on acceleration at about 1/4 throttle. Compression was 110 for all cylinders.

I made these modifications:

-Gone to premix
-Installed primer and removed choke plates
-Reset high and low screws to factory settings

Still hesitated so I upped the pilot jets one size. Now it idles VERY high and won't kill, the engine continues to run for as much as 30 seconds after hitting the kill switch.

Before I dive into it again any advice would be appreciated.

Thanks.

[uncle-buck]

Re: Carb Problem?

I'd recommend going back to stock jettings on the low speed jets first. Then rebuild the carbs with new kits and replace the needles & seats if the needles are worn. Make sure popoff pressure is correct.

Finally, it's a lot of work, but I'd definitely perform a leakdown test on a 7 year old engine - unless you know for sure it has been done recently and there are no air leaks. It's good insurance against catastrophic engine failure and you might find a source of some of the symptoms you described.

Good luck.

[dav_dman]

Re: Carb Problem?

i agree 100% with Buck, carb rebuild and new n/s. You're running on with no spark...askin for engine damage. Stock jetting on that ski is fat, no need to rejet.

[jeffc]

Re: Carb Problem?

Thanks for the advice. It is much appreciated

The needles and seats for this boat are 1.2, correct? I see the marking on the bottom of the seat. One of them is stuck! Any tips on that? How about the spring weight, they look shiny silver. Might as well replace those while I'm in there? What should the pop off pressure be when I'm done?

Do you think there's a need to replace the high and low screws?

Also, what is involved in a leakdown test?

[uncle-buck]

Re: Carb Problem?

Here's a link to the SBT article on testing the case for air leaks:
http://server1.sbtontheweb.com/forum...ad.php?t=16335

I don't have the specs for needle & seat size, spring weight and popoff pressure for that ski. Maybe someone will chime in. You will probably want to buy a service manual if you plan to keep the ski.

You only need to replace a mixture screw if it is worn, damaged, or "mushrooms" at the tip. See the carb rebuild guide for more information.

Good luck and have fun.