XP Fowls Plugs And Wont Idle

[zackman2091]

Ok i have a 96 xp with a newer motor in it (787) well when we bought the jet skis the guy told us that he has to change plugs every couple of uses, well now for us its turning into every use we would have to change them.

When changing the plugs the ski starts right up and runs good for a little while

When going down the canal the ski wont idle, it will idle up and then all of a sudden bogg down and then bogg back up (repeating process till it finally it will die) but it will start back up

I dont know if the jet ski needs carb adjustments which is what is causing the plugs to fowl and if the low idle needs to be turned up

Please help

 

[vallentinerocks]

darn these XP's with fouling plugs! yes please help us poor souls out! I have 3 new sets of spark plugs ready to go as im going to attempt to finally put it on water and try to run mine for atleast 5 to 10 minutes. My plugs wet foul still yet it seems to start everytime and idle, yet sometimes idle is high at 6000, rarely around 3000 which is what it should be when not in water and under load or under 1500 when the plugs are too wet fouled. that is when my ski will not throttle up an will cut out.

ive rebuilt both carbs, HS at 0, LS at 1 1/4 turns open both sides, tried to adjust idle speed to consistent 3k, changed stock grey fuel lines with new fuel lines, cleaned filter/ separator and added see thru filter in from of carbs to verify fuel supply, inspected fuel baffle pickups in tank, cleaned fuel selector, new NGK wires, spark is good fire on both sides, checked compression (both around 126 even PSI so a bit low) and have got quite a bit of the accumulated oil from leaky crank or Rotary valve seals from sitting so long blown out. Mine mostly wet fouls the MAG side cylinder plug. when pulling that plug, it appears as if its barely getting any burn at all, just a mixture of wet and a little black... the PTO side plug will mostly be dry and obtaining a dark brown burn... but yet sometimes it still wet fouls too.

Sorry for jumping into your post, but we probably have similar issues, and was wondering if you have checked or also done anything ive already done and maybe these fine knowledgable souls can help us both out.

 

[zackman2091]

Completely fine for you to jump into the thread any info is good info

But mine just seems to be that the plugs are just gettin wet in the water havent really tried to hook it to a hose kit and see how it runs then. Mine also is just wet and a little black (also smells little burnt/gas)

My ski runs great wide open on the lake and once it is past idle/giving it some throttle it sounds fine

I havent really attempted anything you have done because havent looked into the issue to much, my dad wants to sell the ski and get a newer 3 seater beucase if he fell off he wouldnt be able to get back up, so im trying to find out if i should buy the ski off him because i like the power/how fast it is because of the 787. Our other gs has the 560 or what ever the engine is and i just like having the more power

 

[Dr Honda]

Do you still have gray fuel lines? (both of you)

If you are fouling plugs... check the oil pump adjustment. If the cable comes off... the pump goes to "Full" oil.

 

[vallentinerocks]

Yes, I recently changed all the stock grey fuel lines to new fuel lines... some were a little rotted at the ends on the stock grey ones. as far as the oil pump, one of the last things i did was replaced the oil cable with a new one because i accidently put a bind in it because i didnt see it under one of the carbs when i was bolting them down. so i had to replace it because it was damaged. i put the new cable on without an issue, but was there a certain method or positioning of where it should be when you place the oil cable in it? just wondering. seems to be working right.

 

[D 5UPE]

Maybe you damaged the carb inlet manifold gasket. Make a new one and see if it clears. You may have damaged the mating surfaces so double up on gaskets. Hope that helps.