98 gtx will not run in water, runs fine on trailer put in water bogs down

[ald44mag]

I have tried everything I can think of, the carbs look clean both seam open pump works fine sprays in both carbs, lines clean, inner filters clean, set low and high jets, compression 150 on both cylinders, checked rave's and cleaned, engine smoke excessively when running mixture is premix 3oz per gallon of fuel, fuel is 91 oct. fresh. doo ran fine last year and winterized before storing now runs fine on trailer put in water bogs down and if you can start it it will not run any RPMs at all and will finally die. put on trailer and it will scream, starts at the touch of the button. the engine was replaced last year and has very few hours on the SBT premium engine. I will appreciate any help on the 951 engine, I have alot of hours in trying to figure this one out,

 

[seadooya]

diagnosis you did, was that prior to winterizing or now?

 

[ald44mag]

The diagnosis is now and the winterizing was last fall, I have been working on this foe about 2 weeks now. ran fine last fall, we put stabil in the fuel fogged the cylinders blew water out of engine. thats all we did covered it up and put in barn for the winter. any help please

 

[seadoosnipe]

Troubles...?

First, you do not need to run 91 octane fuel... You'd be better served running 87 octane. It's a colder fuel but runs well in the 130 hp 951 engine.

You need to get a bit more info... When you put it in the water, if it starts, let it run till it dies. Then, pull the spark plugs ASAP and see what they look like. Your looking for signs of water. So, pulling them as soon as you can is important. Wait to long and the water will evaporate.

When your in the water, if you can get the start, just about the time you think it's going to die, pull the choke quickly and release. Is there any difference?

Manifold pressure? Have you made any changes to your air intake? Your air flow cowling is in place correct? That part has your flame arrestor in it and is needed to create a vacuum on your manifold, normally referred to as manifold pressure. If you are running open carbs, then your not going to run very well if at all.

If your running premix (which I would hope your not), you need to make sure you are using the correct oil. You should be running a non-NMMA, non TCW-3 type, low ash oil. I suggest you look for a oil measurement cup, they sell at just about any place that sells weed eaters etc... and premix 50:1. I bought mine at Lowe's several years back. The cup has all the different oil to fuel ratio's and is great if you are mixing unequal amounts of fuel....:cheers:

If you think your premix is causing this, take out your plugs and see how black they are, or how much oil build up you have.

 

[Bills86e]

Fresh fuel,Hope that means you emptied system, not "added to". Did you crack the
separator/filter bowl when you did your pre-ride dump? could be sucking air.
Symptom is a lean condition. Bills86e

 

[ald44mag]

could it be in the firing?

the engine seams to be flooding lots of smoke when running on water hose but accelerates and runs great. plugs are black, plugs are firing hot when taken out. it will run fine on the water hose for as long as you want it to. put in water bogs immediately if you pull the choke it dies instantly. again it seams to be flooding.HELP please I need to get this one fixed bad<<<

 

[seadooya]

clip plug wires, double check the oil pump alignment. Possibly you fogged alittle too much? Same gas as last year? if so, all the oil settled to bottom of tank?

 

[voodoo]

Has any pressure test been done on the block? you mentioned SBT in there, they have a reputation of boring all the way out, is the muffler water regulator working, not plugged up? If you have access dip with the boat still on the trailer and see if trouble begins when the pump goes in the water, something is allowing water to enter.

 

[tballman]

Did you ever slove this issue? Mine is doing the same thing, starts/runs great out of the water, will not start in the water?