95 Force 120hp bogs out at full throttle

[Garrgh]

Hello all,<br />I just got my motor back from the mechanic and put it in the water yesterday. I'm pushing a 24' aluminum pontoon boat.<br />It starts and idles fine, has good compression, but dies after a few seconds when I go WOT. I was told the fuel filter had been cleaned and the compression is good, as well as the spark. It will restart after a few seconds and run fine at 1/2 - 3/4 throttle, though I haven't got it up faster than maybe 10 mph. The #4 spark plug seems to be dirtier than the others.<br /><br />It has had a new stator (the red one) and trigger installed.<br /><br />Any ideas? Parts and labor are hard to come by here.

 

[eurolarva]

Re: 95 Force 120hp bogs out at full throttle

Is the primer ball staying firm? When this happens try loosening the gas cap. Your gas tank may not be venting and causing restricted fuel flow. It could be a sticking float valve in one or more of your carburators. I would start with replacing the diaphram in your fuel filter. Also verify that the valve seats have good spring tension and that the valve gaskets are not broken. If that dosent help you may have to rebuild and clean your carbs. If you kept gas in the carbs for a long period of time they could be gummed up.

 

[Garrgh]

Re: 95 Force 120hp bogs out at full throttle

Thanks. We're going to check timing and clean the carbs tonight. I took it out last night and she ran fine except for the WOT (still dying), and it was missing a little. It seems to bog down under load, like in a tight turn...

 

[Garrgh]

Re: 95 Force 120hp bogs out at full throttle

This is follow up to what caused the problem. My mechanic told me I had 125 lbs of compression on all 4 cylinders. However, when I checked them #4 had 0 pounds.<br /><br />The piston had a hole in it the size of a dime.<br /><br />Got parts, rebuild time...

 

[OBJ]

Re: 95 Force 120hp bogs out at full throttle

Garrph....don't forget about the carbs. Rebuild them along with the rest of the engine.<br /><br />Look for any deep pitting on the head for #4 cylinder that could hold carbon. This could lead to pre-ignition and your rebuild won't last long.<br /><br />Good Luck and keep us posted.

 

[WhiteHorse]

Re: 95 Force 120hp bogs out at full throttle

I have two good powerheads sitting around.

 

[WhiteHorse]

Re: 95 Force 120hp bogs out at full throttle

I have two good powerheads sitting around.