25HP Idles Low in Neutral

[LaqueRatt]

Motor runs well, starts on one pull. Only problem is it idles low in neutral and turning the tiller doesn't do an awful lot. Just turns a hair is all. It revs so low even with the throttle fulling cranked that the motor wants to die. When it does it's hard to start. Once warm though all is good. Can this be adjusted? I read that it can, but don't know how to do it exactly. I'm thinking there is something on the starboard side that needs tweaking. If somebody could point it out I'd appreciate it.

I hope that makes sense. What am trying to say is she won't rev up in neutral. I know it's supposed to be limited, but not this much. The actual idle isn't the problem.

 

[saltchuckmatt]

Does it rev up in gear?

 

[LaqueRatt]

Yes it does. The issue is the throttle barely moves until I put it in gear. I know there's a stop to limit speed in N. I just don't know how to adjust it.

 

[saltchuckmatt]

Yes it does. The issue is the throttle barely moves until I put it in gear. I know there's a stop to limit speed in N. I just don't know how to adjust it.

This is the nutruel lockout mechanism. There is an adjustable rubber stop tied into it.

Does this motor run fine on a boat, in gear in the water?

 

[saltchuckmatt]

This is the nutruel lockout mechanism. There is an adjustable rubber stop tied into it.

Does this motor run fine on a boat, in gear in the water?

Forgot the picture and it wouldn't let me edit.

 

[LaqueRatt]

Yes, motor works quite well actually. Looking at what you circled, are you referring to that screw? I don't see anything rubber, maybe it's missing, but I'm hesitant to move the screw as it doesn't seem like it would have any affect on that cam. Or the tab that rides on it. I'm temped to try to bend that tab, as that would definitely make a difference, but it looks like a stout part and not something that you should adjust.

Going back out to look for the rubber piece. I'll try to get some better pics. Thanks for the help.

 

[LaqueRatt]

Could it be something with the tiller? Like maybe it's not installed properly? The pointer does not seem to be where it should be. Either in N or in F. The first 3 show the limits on the handle. Both fast and slow. Plus the position on the stop. The last 3 show it in Forward gear.

 

[racerone]

That screw in the picture has to do with the lock for the starter.----Recoil should only work with motor in neutral.-----Do not adjust anything on this motor if you are NOT sure of it or the results !!!

 

[LaqueRatt]

OK, thanks. I learned something today. I won't mess with that screw. Any ideas why this motor barely accelerates in neutral? Thing is I start it with nearly as much throttle as I can and then it idles at like 500 and turning the handle may get me up to 700 or so. Which is too low for when it's cold. Once she's warmed up she idles nicely at low revs and never dies. In gear or not. This motor does though idle lower than any other I've had and the idle screw on the side doesn't seem too responsive. I'd like to kick it up slightly, but she won't have any part of it!

 

[Crosbyman]

btw what are the compression #s

 

[LaqueRatt]

Both the same, either 130 or 135. Think 135. Motor appears to not have seen much use, but it's passed through the hands of a couple knuckleheads, not including the present owner (me). So from what I'm hearing should I assume there is no adj for high rpm limit in neutral? I sure can't seem to find one.

 

[Crosbyman]

this may be of no use but on older RD's neutral speed is limited asexplained in the old Johnson manual

you may want to compareengines to see if the speed control method was not carried over to your more recent 25hp.

I do not know if pulling out the cam under the FW would help to open up the carb throttle plate just a bit . line up the cam follower on the cam "bar" and pull it out the cam a bit to open the throttle plate to see what it does to RPMS ... if no improvement just readjust it to just touch the cam follower at START

 

[LaqueRatt]

Thanks, that's a good read. Now pretty sure am on a wild goose chase and no adjustment exists. Maybe it's time to go back in the barrel to see if tweaking the low speed setting may help some. Does anyone think it's normal to not be able to rev it up in N? I know it's limited, but limited to under 1,000?

 

[Crosbyman]

why would yout to high rev above... 1000 rpm in neutral anyway ???

just let the engine warm afew minutes

 

[ct1762@gmail.com]

Thanks, that's a good read. Now pretty sure am on a wild goose chase and no adjustment exists. Maybe it's time to go back in the barrel to see if tweaking the low speed setting may help some. Does anyone think it's normal to not be able to rev it up in N? I know it's limited, but limited to under 1,000?

its idle speed in forward gear that matters. to adjust there should be a screw on the port side just under the flywheel infront of exhaust cover. these never rev up high in neutral. make sure throttle butterfly is exactly horizontal at WOT, and cam roller just starts to open said butterfly when it hits the hash mark on throttle cam. if it opens way after, it wont rev up much at all.