72 Merc 800 loses power in gear, idles fine

[Braylon]

Was running my 14' Starcraft this weekend, on Saturday the motor started fine, and ran perfectly all day. Sunday a.m. took her down the ramp, fired right up, let her warm up for five min (as usual), and as soon as I plopped her in gear, she sputtered and died. Would start up and run, but as soon as I shift into gear and increase rpms, she chugs and rattles. I can back off the throttle and keep it running in gear, but even turning the wheel seemed to aggrivate the condition. Back at the dock I could start, and rev the motor as high as I wanted, but no mojo in gear. Fresh plugs, wires, gas, fuel line, vent open on tank, fuel line isn't pinched. What the heck??? It ran fine the day before. Where do I start?

 

[Chris1956]

Re: 72 Merc 800 loses power in gear, idles fine

Braylon, It sounds like your new fuel may have some ethanol which loosened some crud and clogged the carbs. Sounds like a carb clean and rebuild is necessary.

BTW -is that 14 footer rated for an 80HP motor? Most aren't. Sounds like you need to keep the wheel steady while cruising at high speed.

 

[Braylon]

Re: 72 Merc 800 loses power in gear, idles fine

Thanks Chris, I'll start with the carbs and rebuild them this weekend. I never run ethanol in my baby, and even have a new gas tank. I use both fuel stabilizer, and enzyme treatment, but like you said, may be crud in the carbs. Oh, and yes the boat is rated for the Merc 800, it is the original motor on my ride. She'll keep up with most anything on the lake. Except the Park Ranger. I'll post again if that doesnt do the trick.