1988 Yamaha 80 hp cuts out??????

[stickymess]

I have re-built the carbs and replaced the fuel lines/tank/primer, done a complete service according to the manual. Problem is the motor starts great and idles great and then as soon as the revs go over 2500 the motor sputters and dies.I don't think that it is a fuel issue but not sure what else it could be.Any suggestions will be apppreciated.

 

[ivar]

Re: 1988 Yamaha 80 hp cuts out??????

Had a similar problem on my 92 60hp, it was one of the coils that shorted out when rpms reached 3500-4000.

 

[bigbrownbuku]

Re: 1988 Yamaha 80 hp cuts out??????

determine that it is firing on all cylinders while the problem is occuring. this usually involves me hanging on over the back of the boat while under way yelling throttle commands to the apprentice. i can almost visualize rodbolt rolling his eyes . the correct way is to install the right test prop and do it in a tank etc, most dont have that luxury. eitherway you will need a set of chicken pliers (insulated/plastic pliers for pulling spark plug leads). if you do choose the first way dont fall in. i hear people arent the top of the food chain floating in the water down your way

 

[stickymess]

Re: 1988 Yamaha 80 hp cuts out??????

HaHa BenC, you definately don't want to fall in around here, a guy was eaten 100 feet from the launch while spearfishing just a month ago,all they found was a diving mask.Back to my motor, it runs fine with muffs on, with all cylinders firing,but as soon as it is under load it sputters and cuts out, I remember with my last boat when the coil went, only the one cylinder would die ,now the whole motor cuts out.