35 hp Force Starving

[terry]

" I have an early Force 35HP o

" I have an early Force 35HP outboard.

Was running boat the other day at WOT. Motor started to lose power as if I was cutting throttle. Then couldn't restart the motor.

Found a leak in the fuel bulb, and replaced the line from the tank to the motor. Also checked and tightened all clamps in the fuel system onboard the motor itself. Checked the tank, carb-bowl, fuel pick-up, fuel-pump filter for dirt and found none. Problem happened again, and it was very difficult to restart the motor again.

I have also recently replaced the plugs, and the spark plug boots.

I have never had starting problems with this motor, it always started on the first crank - hot or cold. This season however, it has been harder to start than ever before.

Any suggestions would be appreciated. "

 

[tonyob]

"Terry,

What do the spark p

"Terry,

What do the spark plugs look like? Did you check for spark when the motor became difficult to start?

When you removed the float chamber did you check the main fuel jet? This screws into the body of the carb from the starboard side at the bottom of the central column.

I think you should remove the cylinder head and take a look inside. You may have a burnt or leaky head gasket.

"

 

[terry]

" Both times it 'starved&#

" Both times it 'starved' I didn't think to check the plugs. When it has been hard-starting since then I checked the plugs and they looked good. Not fouled, but not burned dry either. Gap is set to factory spec and they are new plugs.

Checked the main jet, and it was clear.

What would I see on the cylinder walls if the head-gasket is burnt or leaky? Will a compression test tell me this or do I have to wreck a potentially good gasket to check?

Thanks for your continued help! "

 

[tonyob]

"Terry,

A compression test

"Terry,

A compression test might help you, but if a head gasket has s small area that is leaking it might not show up on a compression test.

Usually, if the gasket is allowing water to get into a cylinder, it is visible on the spark plugs as a greyish, muddy deposit.

See if the spark can jump a gap of 1/4 inch. Try 7/16 inch also. These distances don't have to be exact. Hold the plug wire near a ground for this test and use an insulated tool to hold the wire.

Try turning the flywheel in a clockwise direction by hand and feel the compression in each cylinder. Do this a few times and see if you note any difference between the cylinders.

If the plugs appeared wet and you don't think it is water, you may have an ignition problem.

If the ignition checks out good, I think you should take the head off and look inside. Examine the pistons for excessive play and the cylinder walls for scoring. If you have a problem here it will only get worse.

It might pay to check the output from the stator to the ignition module, the output from the module to the coils. Sometimes when the stator is weak it becomes difficult to start the engine because there is not enough electricity at cranking speed.

"