need some advice please

[eyedoktr]

My '96 Johnson 25hp started acting up this past weekend. If I give it any gas in forward, it hesitates, bucks and almost stalls. In neutral or reverse, this doesn't happen. It was a long drive back to the launch. Does anyone have any ideas on what's wrong ? Thanks. Pete

[eyedoktr]

Oh c'mon, I know there are experts out here, or at least those with suggestions.

[RANGER]

Sorry, but I'm clueless, especially because you said it's fine in reverse. When the motor is in reverse it is no different then forward. It's a function of gears and pinions not motor direction and revolutions. Having said that, if you sheared a forward gear or seal the pieces may be getting wedged in the forward gear teeth and seizing the engine. It will be in the "bullet" of the lower unit. I don't know. It's a guess. :-(


RANGER


"KEEP YOUR LINES WET, YOUR POWDER DRY and THE BEER COLD"!

[RANGER]

eyedoktr,

If it turns out to be the gear/seal thing, be forewarned - I have rebuilt two of them over the years and it is a real pain in the a$$, requiring special tools most "shadetree" mechanics don't have. Better to take it to the professionals, honest.


RANGER


"KEEP YOUR LINES WET, YOUR POWDER DRY and THE BEER COLD"!

[SeaCat]

Had a similar problem with a big motor (235 hp) and it was caused by two entirely different problems on different occasions.

First I would check the fuel related items -- carb, lines, filters... I had a bad fuel filter and in forward it needed a lot more fuel than in neutral or reverse. Consequently, only saw the problem when trying to get going on plane. Trolling at slow speed was no problem since it was getting enough fuel for 3 mph :-).

Second area that caused the problem was a single bad power pack on the 6 cylinder engine. It was sluggish off the line and would only get to 2500-3000 RPMs instead of 5500 full out. Again, in reverse, rev'd in neutral, and at troll it behaved just fine. I don't know if the smaller engines have such a thing or not. Basically though it was not firing on the 6th plug under load -- not missing at idle though -- apparently it only failed when it needed to send a large amount of charge through the power pack and the pack was not up to it. Put on a new one and was back in business.

Ryan

[W-eyes -guy]

You got the backtrolling model??
:-)

[mikie]

My suggestion is to take it to a shop. Your safety on the water is more valuable than the few bucks it will take. Know of any mechanics who make service calls over the phone? Me neither, same issue as asking us. Get a dealer to look at it and get back outside and play. m

[Paul Dickson]

One long shot may be water in the fuel tank. When Idling or out of gear or in reverse the tank and it's contents will be level, when accelerating forward it will shift the fuel and maybe enough to pick up any water in the tank. As another post noted a restricted filter or one with water setting in the bottom of the filter and being picked up when you accelerate forward could cause a similar symptom.

[the new guy]

An old plug can cause this type of problem when the engine is under a heavier load.
Especially with only 2 cylinders, I would start with fresh plugs.
I own a 96 Johnson also and really dont care for the way it runs even when properly tuned.
I have the new style carb on it that you can't adjust and it has lag spots in acceleration just out of idle.
Does yours do the same thing?