Not going into forward

[tjello327]

Hello forum,
I have a 1986 125 hp force. I just got done fighting the ignition system all summer & got this thing running good. I took it out for my first test run and it runs pretty good, but as I left the boat launch, it would not go into forward gear smoothly. It would just grind. I adjusted the cable all the way in and out and had no change. I disconnected the cable and manually shifted the shifting bracket with my hand as far as it would possibly move and it would maybe go into gear very briefly and pop back out and grind again. My guess is there must be some kind of drive dog inside the lower unit that is rounded off some. I dont think it is the gears because reverse stays in better (not quite right though.) I have not ripped into the lower unit yet but will very soon. The prior owner said he had to pop it into gear fast. Any ideas where I should start looking for this problem? Im sure one of you boat mechanics have been into a lower unit or two can give me some good advice!
Thanks

 

[Frank Acampora]

Re: Not going into forward

Yes! The lower unit has drive dogs. There is a dog clutch between the gears with three dogs on each side. It is splined to the prop shaft. The clutch is slid forward or backward to engage the dogs on the appropriate gear. The gear turns the clutch which turns the prop shaft.

Because it is dog drive, you need to "snap" it into gear. If you "ease" it, the dogs rattle against each other and wear.

Since you have the problem in both forward and reverse, it is most likely that the drive dogs are rounded and will pop out of engagement with application of power.

The dog clutch alone is about 130 bucks new and the gear set is prohibitive in price. If you are handy with a Dremel, you can dress the worn edges with a carbide bit and get more life out of them.

Otherwise a good condition fully functioning used lower is the way to go.

 

[tjello327]

Re: Not going into forward

Thank you,
I took the lower unit apart last night and that is the problem. The forward side dogs are not square anymore. I am a Machinist so I was going to try to recut the worn area with a carbide endmill and do the same with the gears. I cant see why this wont work. The amount of material to be removed will be less than 1/16". The integrity of the dogs and gears should not change much. Quick cheep fix I hope! Thanks again for the advice.

 

[tjello327]

Re: Not going into forward

Well got all the worn parts milled square again. Should have it put back together this weekend (I hope.) The gear set and a drive dog cost would be about $800.00 new from Crowley.com and If I made them new It would be higher yet to just make 1 set. This fix better work, I dont think a complete Force engine is worth a whole lot more than the new repairs in a lower unit.

 

[Frank Acampora]

Re: Not going into forward

As you can see, the drive dogs have a lot of meat on them. Squaring them on the end mill is way more accurate and faster than the few I have done by hand. as a machinist, you should have also noticed from the machining marks that the factory made them by milling (But most likely before they were hardened). It should fix the problem. Just be sure to look up past posts and adjust the linkage so you get equal throw in forward and reverse.

You should make a few bucks out of your hobby and do it for others. Charge around 30 - 40 bucks an hour for your time, plus shipping. It will still be a bargain for those people who have worn gear sets.

Matter of fact, if you are interested, send me a personal message with your email address.

 

[tjello327]

Re: Not going into forward

Thanks,
I will right now. If any one else is interested, I will do the same if asked.