boomvang

I recently purchased a 2002 GP1200R with around 50 hours on it. It was owned by a relative who didn't use it much for years and not at all in the last 3 years. He had let gas sit in it for at least the last 3 years over the winter without running.

When I changed the plugs and put in fresh gas along with some dry gas it ran fairly well but would occasionally bog on start up acceleration. Otherwise, the performance and power seemed great.

Thinking that the bogging might be due to varnish build up in the jets from letting gas sit in it for years, some fuel injector cleaner was added to the gas. I took it on the water and after about 5 minutes of WOT I noticed a sudden loss of power and it started making a bogging sound.

Now it always has VERY sluggish acceleration and sounds like it's bogging. It will only get up to about 40. Every once in a while when running at WOT it will momentarily "come to life" and take off with normal feeling acceleration lasting for just a second or two and then back to running bad. It seems like it can also be momentarily brought to life by getting it bouncing on waves. I have also found I can make it "come to life" by getting up to 40 and then cycling the throttle from off to WOT. About every 3rd or 4th cycle, it will take off great as soon as I hit WOT and then after a couple seconds it goes back to running bad.

I have changed the plugs and the fuel filter, got the old gas out and filled with fresh premium...no change.

I would really appreciate suggestions.

My best guess is that the root of the problem is the old gas sitting in the carbs for 3 years and turning to varnish. I'm guessing that the fuel injector cleaner broke loose a chunk of something which is now sitting in a bad place. I know when I have made the mistake of leaving gas sit over the winter in a lawnmower, the only fix is having a shop soak the jets in a solvent or do a carb rebuild. I'm wondering if I need to rebuild the carbs. How hard of a job is it? Is there a good DIY? I'm a fairly competent mechanic, but this is my first wave runner.

The suddenness with which the problem occurred makes me think there may be an easier solution than rebuilding the carbs?

Thanks and sorry for the long post.

Steve

CWOLF

Try adding Sea Foam to the your fuel. 1oz per gallon is the normal recommended amount but, for something as stubborn as you have described, try a stronger mix. Each can of Sea Foam is 16oz. It may take some time for the treatment to work but, the treatment will dissolve just about any blockage with a little time and patience. I had a similar issue with a XL1200LTD and Sea Foam cleared the problem after using about 24oz. of the product, 10 gallons of fresh 93 octane fuel, and a few days of running at various speeds. Performance improved each day after sitting approximately 24hrs. between runs. If you want to perform an extreme attack on the blockage, you can pull the fuel filter, submerge it in the Sea Foam until the filter is full, carefully re-attach the fuel lines to the filter and try to start the engine. This will inject a 100% solution Sea Foam into the jets. Try this a couple of times and let it sit for a day. If the blockage is gum or varnish, the 100% solution of Sea Foam will almost definitely dissolve it by the next day. Good luck.