1999 Sailf Fish 0x66 BOGGING

Gianni

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Hey guys, havent posted in a while...

I just took boat out of the harbor, fueled up and had no problems at low rpms.

As i drove the boat up to the 20's and low 30' i experience bogging on both motors.

One engine totally shut off afterwards and only one to pull back into marina.


I have changed fuel separators on both the big canister and within the engine.

New impellers.


Has anyone else experienced similar issues? We cleaned out VST tank and found a little gunk within in and cleaned it.


Any other opinions?


Thanks so much... :-| :-|
 

DennisG01

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Did you get any alarms when it shut off? Anything showing on the gauges (low oil, for example)? Just to be clear, it was bogging (struggling to run, not responding to throttle input), right? It wasn't shutting down like someone flipped a switch?

Where both engines running off the same tank?

The first guess (as that is all we can do with limited info and not being there), is a restriction in the fuel line - like a blocked vent. What did the fuel bulbs look/feel like when it shut off? I assume that one of the first things you did after it shut off (or as it was bogging) was to go and pump the bulbs? Inspect teh fuel vent fitting and try running with the fuel cap off.
 

Gianni

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As per the bogging, it wasnt as if someone hit a switch. It was struggling to run. No alarms went off. A mechanic came to the boat a week later and said it seemed the engines were fine but we never took it out for a run. He did clean the vst cansiter and found some gook within it, i just dont seem that it can be that being the problem.

Im at a loss these past 3 years with these motors, never had a problem and now recently theyve been acting up. My next move unless i see other tips; is to unscrew water separator, drain it and see if all is well.

As per the primer balls, when we turned motors on at dock, the primer balls felt fine.

Any other thoughts will help.

I appreciate your quick reply..

Can this be a possible spark plug issue?
 

SkunkBoat

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As with any problem, the thing to do is get more info before randomly changing things.

VST cleaned out gunk...didn't fix?

You have 2 motors. Both bogged down. How many tanks?
One motor died? one got you home? One still doesn't run?

Narrow down problem to fuel or not.
Use different tank
Jumper in a tank
verify flow by disconnecting hose and pumping fuel into a can (using primer bulb)

It is not likely a spark problem if both motors do it. Not an Impossible coincidence but not likely.....
 

seasick

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What does 'cleaned the VST gunk mean'?

Did you pull the vst apart and inspect the filter/screen?



You either got crap in the fuel or water perhaps. Take a look at the motor mounter clear bowl filter. It should be mostly full but not completely full. There is a red ring in the bowl and it should be at the bottom. It floats in water so if it is higher up, you have water.

Since it happened to both motors and after fueling, I suspect a bad batch of gas.
 

Andrew93

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If there was residue in the VST make sure you replace the filter, even if it looks clean I bet it has a lot of restricted flow. I would also take the injectors out and have them cleaned, the turn around is a week or less at most places you can mail them in.

I would also replace the low pressure fuel pumps and assure there is not any water in the fuel.
 

Ozz043

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I had a similar situation, OX66, luckily one engine only though like you.

Turned out to be the high pressure fuel pump inside the vsr, engine was fine at idle to 3000 then had no guts, then would not start after a few amattempys to clear it.

To check turn ignition on with an ear against the vsr, you should hear pump humming, if it is quiet the pumps not working ..... then press in the Schroeder valve and see if vsr is pressurised....

No hum no pressure....pump not working
 

Gianni

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That’s very interesting. I will look into that as well. There was some crap in there and we cleared it out .. I’m gonna take a looksiebsunday again with all the advice I see here. Thanks for your input
 

seasick

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If you take apart the VST , do not run it dry after putting it back together. Use the primer bulb to fill it. It will take a bit of time and pumping but eventually the bulb should get firm. Running that pump dry can fry it.

The rubber gasket under the VST top plate can be reused if it isn't damaged. That said, it can be a pain to get it back in the groove. Two tricks are to use some grease to help it stay in place while assembling and putting the rubber gasket in a freezer for a while to make it shrink a bit. The old gasket tends to expand when removed.

Sometimes when the vst screen is clogged, you can replicate the symptom at the dock by running the motor in gear and increasing the revs. Of course you need to make sure the boat is tied off securely.
It might help if you can describe what the 'gunk' you cleared out looked like, especially if it looked like a whitish powder.
 

Gianni

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This upcoming week I’m going to try some of your opinions. I had a Yamaha mechanic come down whom. Leaned the vst tank. He claims the boat should run fine but I’m not so certain