Newbie, Evinrude '88 70hp problems...

[slugdog]

Hi y'all. I just bought a '88 24' Lowe pontoon with a '88 70hp Evinrude. The guy who sold it to me had just put on a new power pac and trigger switch. Today, after a couple of days trying to get it to start {it ran fine when I tested it with him}, got it fired up. Had to tap the choke solenoid a couple of times to get it to click. Got out on the lake, and it ran fine at half speed for 45 minutes. I then decided to "hammer down", {don't we all}, and after about 2-3 minutes, it started going from wide open to half speed, back and forth, every couple of seconds. When I backed off on the throttle, it continued to do the same thing, only slower. Plus it has no idle at all. I figure dirty carbs, as I replaced the tank, which had a air leak, today. Any info would be great. A guy told me today to bump the choke when it did that??

 

[tashasdaddy]

Re: Newbie, Evinrude '88 70hp problems...

bumping the primer (choke) is a sign of fuel starvation, is the vent open and clear on the fuel tank? have the fuel hoses been replaced.

Ethanol and fuel lines
replace all fuel line with Alcohol resistant lines. Ethanol deteriorates, the rubber lines, then they start to sluff off on the inside, going directly to the carbs. Settling to the bottom of the bowl. Contaminating the carbs high speed jets. clean a rebuild carbs, flushing fuel line before connecting to carbs

also could be a weak fuel pump. are you using the VRO2 or are you premixing your fuel?

 

[slugdog]

Re: Newbie, Evinrude '88 70hp problems...

Vent's open, bought a new tank today. Thanks for the good advice on the fuel line, as I have wondered about the effect of ethanol. I'll change those out when I get my carbs worked over, like next week. I premix my fuel, 5.2 oz to 2 gal. with quicksilver, info I got from our local boat shop. I know less about outboards than I do women, been married 30 years.....