1997 25 hp mercury problems

[wishniwuzfishn]

Hi,
I just purchased a 16' aluminum with a 1997 25 hp merc w/electric start. It seemed to run fine with the ear muffs on and initially when I got it in the water. The problems started when I got it out in the narrows at a higher speed, it would seem to rev up and lose speed or almost seem like it was in neutral and at one point I had to decrease the speed and then take it back up again in order to feel like we were moving. After turning back and entering the harbour it wouldn't slow down to below about 10 knots [guessing] and I had to shut it off in order to stop. after that, upon start up it would rev way up in neutral and I had to quickly put it in gear only to have it tear off again at high speeds. Any ideas would be appreciated as I got ripped off by the guy I bought it from who says it runs perfect and I just want to get out fishing with my kids. Thanks

[verado7]

check your throttle cable at the motor and make sure the link arm is returning fully to the stop . then post back .

[will941s]

I had a problem kind of like that on mine, where it would rev up by it's self in neutral, and run at really high RPM's on it's own. Then it would backfire and all kinds of stuff. Found that the primer on the side of the carb was cracked and the carb it's self was clogged with the decayed innards of my fuel line from the ethanol. Ran great then it happened suddenly during a fishing trip. After rebuilding and cleaning the carb the problem never came back. Like Verado said, check the shift and throttle linkages and make sure they are resting at their appropiate rest points, if not find out why. Also when they are engaged (like half or full throttle) make sure there is'nt a whole lot of free play in them. Keep us posted. Could be a interesting forum.

[wishniwuzfishn]

Hi Thanks,
The throttle was definitly sticking. Seems to be fine after moving it fully back and forth a few times. The engine is no longer revving to high in neutral, However I'm not sure about the problem with the engine revving up at higher speeds. I've been told the prop may be spinning on the hub due to a plastic or rubber bushing? being worn out. I've decided to pay someone to have a look at it ,pull the prop off and take it out for test. I'll post his findings when I get them.

[will941s]

Good idea, on my props with a rubber hub I make a mark across the whole hub, so if it spins the hub, one quick look and you can tell.

[verado7]

the high end rev could be the prop hub come loose ( spun prop ) - put your spare on and see if it goes away _ you carry a spare right ? - sucks when you spin a prop miles from shore - you can them rehubbed fairly cheap at a prop shop .