won't run

[t.martin]

1986 85hp force. When I try to start it sometimes it run for about a senond and then shut off. Other times it will backfire out of the exhaust. The carbs are full but it acts like it is running out of gas. The flywheel key is alright. Can it that far out of time.

 

[eurolarva]

Re: won't run

Manual says this for backfire through carb<br />Cracked spark plug insulator<br />Carbon Path in distributor cap<br />Improper timing<br />Crossed spark plug wires.<br /><br />If this motor is new to you it could be any one or more of the above. If motor was running good then crapped out chances are the timing is right. The timing does not stray on these motors once they are set up. Plug wires reversed is common. Did you actually remove the flywheel and look at the flywheel key?

 

[t.martin]

Re: won't run

This motor is new to me. it is backfiring through the exhaust. I pulled the flywheel to check the stator wires. The key is there. The mark on the flywheel lines up with the mark on the block when #1 is tdc. It seems like it isn't pulling gas through the motor. I took a spray bottle with mixed gas and sprayed each carb (butterflys open) it still wont start and run. I also pulled the reeds and they seem okay. Could it be fuel pump? If it is it doesn't make any sense.

 

[t.martin]

Re: won't run

I forgot to mention that this motor was supposedly freshly rebuilt. Is there something they could have done wrong internally that would cause this symptom?

 

[eurolarva]

Re: won't run

Book says backfire through exhaust is improper timing. I hope someone else here can help you with timing.<br /><br />I agree fuel pump is not causing this problem. IF premix being sprayed through the carb dosent fire it. Have you tested your spark plugs? Pull them out and ground the tips with the wires attached. Crank it in a dark room and verify you have a good blue spark

 

[t.martin]

Re: won't run

It must be timing, because it has pretty good spark. I just don't understand how sometimes it will start and rev up for a couple of seconds and then shut down like it ran out of gas if it is a timing or spark problem. I have an extra motor for parts that I have totally stripped a swapped parts with. I probably need to check compression even though the pistons look brand new. (Force engines are enough to make you want to quit boating.)

 

[t.martin]

Re: won't run

Should I try spraying ether around the intake plates to see if it has a leak?