90 hp mercury

[jerkputter]

I have a 1999 Mercury 90hp outboard on a pontoon boat. When I parked it last year it was running great. I winterized it and the first time I tried it this season it is having some problems. Runs great at full throttle, idles fine at about 2000 rpms or at 8 mph. When I go at a good cruising speed for a pontoon boat it bogs really bad and will then just correct itself all of a sudden. Sunday it bogged and went dead and wouldn't crank for approx 5 Min's. I pumped the bulb and it finally cranked. You think I will have to remove the carburetor's and clean? I tried some sea foam and did not help. Would a bad fuel pump cause this? Thanks

 

[Mi duckdown]

Re: 90 hp mercury

Water in the tank, or fuel pump.

 

[1nebel0]

Re: 90 hp mercury

subscribed

 

[mikeneal]

Re: 90 hp mercury

Definitely sounds fuel related. Could try on stand alone tank to test fuel in the tank. I had somewhat similar surging issues with my 90 elpo and rebuilt fuel pump and cleaned carbs and solved it. ( carbs have to come apart to clean them, sea foam won't help)

 

[jerkputter]

Re: 90 hp mercury

Thanks, I will give that a try. I believe you are probably correct but I guess I wanted to hear a quick fix. Thanks again. Tom

 

[Jeep Man]

Re: 90 hp mercury

Bets are on the fuel pump. Other models have an issue with mid throttle sputter.