75 Chrysler 90hp WONT START

[75WhiteFLoyd]

Ran like a champ for about 20 minutes then i hit full throttle and it died. Hasn't started back up since. Wants to start but won't. Fuel ball will be hard till i crank it over then it goes soft again (fuel pump?). Got great spark from all 3 wires. When i remove plugs they are covered in fuel. Any ideas or help would be greatly appreciated. I'm about to throw in the towel and be at the mercy of the mechanic.

 

[mikesea]

Re: 75 Chrysler 90hp WONT START

there is a chrysler/force forum on Iboats also.However.Im thinking your fuelpump has blown a diaphram and is flooding your engine thru the pulse port that operates the fuelpump.You might check by squeezing the ball and looking where the pulse comes from.I dont recall if that engine has a hose that goes to a barb in the crankcase somewhere or if it mounts directly over a port.Either way ,disconnect the hose /or remove the fuelpump and see if gas comes out ,where pulse goes in ,no gas should be in that pulse port

 

[Frank Acampora]

Re: 75 Chrysler 90hp WONT START

When these engines die at full throttle and then refuse to start again, it sometimes--usually-- indicates a major problem. (Sorry) Check compression in all three cylinders before doing anything else. If one cylinder is below 60 or possibly below 20 PSI, then you need a rebuild.

These engines tend to detonate and melt pistons. It happens so fast at full throttle that the operator does not have time to react. It is sometimes called silent damage because the noise of the boat tends to mask the detonation and an inexperienced operator will not notice or recognize it.

 

[75WhiteFLoyd]

Re: 75 Chrysler 90hp WONT START

Well i went out yesterday morning after breakfast (so not to ruin my morning) and did a compression test. Top two cylinders ranged from 80-120 PSI depending on the stroke. The bottom cylinder didn't make it to 20 PSI. I appreciate all your advice. Had to take it into a marine repair. Tomorrow i start selling plasma and look for someone that needs a kidney. haha