Replacing Throttle Control Gear 68 18hp Fastwin

[Fish Magnet]

I have a 1968 18hp Fastwin, runs great but broke throttle contol gear.

1) unable to replace because not enough clearance between steering Bracket and motor housing. Manual states one can remove power head, exhaust housing and gearcase as one assembly. Is that the best way to get enough room to drop control gear in place, or is there an easier way.

2) The bottom pin of the gear sheared off. I noticed that there is a significant amount of movement between the steering bracket and the rest of the engine. I understand that this is to isolate vibrations away from the transom and mounting bracket, but is too much vibration leading to the broken part. Is this a common problem, and if so how to prevent it in future.

I have the part, just scared to start taking apart more than I have to, since motor runs good. If it ain't broke, etc.

Thanks
Fish Magnet

 

[F_R]

Re: Replacing Throttle Control Gear 68 18hp Fastwin

I have a 1968 18hp Fastwin, runs great but broke throttle contol gear.

1) unable to replace because not enough clearance between steering Bracket and motor housing. Manual states one can remove power head, exhaust housing and gearcase as one assembly. Is that the best way to get enough room to drop control gear in place, or is there an easier way.

2) The bottom pin of the gear sheared off. I noticed that there is a significant amount of movement between the steering bracket and the rest of the engine. I understand that this is to isolate vibrations away from the transom and mounting bracket, but is too much vibration leading to the broken part. Is this a common problem, and if so how to prevent it in future.

I have the part, just scared to start taking apart more than I have to, since motor runs good. If it ain't broke, etc.

Thanks
Fish Magnet

Hm-m-m-m, while I respect your word and what you are saying, I find it strange that it won't come out. I've removed lots of them without such extreme measures. In salt water it is common for the pilot pin on the bottom of the gear to get tight because of corrosion around the OD of the bushing--thus the reason for having to disassemble so many of them.

Come to think of it, with the pin broken off it doesn't make sense why you can't slip the gear out. You do have the horizontal gear & shaft out, don't you? And the vertical shaft that sticks down into the gear?

OK, there normally is a lot of flop in the rubber mounts, but unless one is broken that shouldn't be your problem. Perhaps the cross pin in the bottom end of the vertical shaft is tight and can't swivel as the motor moves? Perhaps the pin is tight in the bushing as I just mentioned?

Sorry I can't diagnose it better.

 

[Fish Magnet]

Re: Replacing Throttle Control Gear 68 18hp Fastwin

I was able to remove it easily, since it was broken off. But the new part is not broken and is too tall to fit. I removed the vertical shaft, thinking I could get some more room up top. But the top of the gear is wider than the hole up top. Removing the horizontal gear and shaft won't give me the room I need vertically.

I checked the rubber mounts and they are older but still spongy and intact. Lots of grease all around, also fresh water only. I will check the horizontal connection as that may have been the problem.

My question is how to get the new intact control gear in? Just not enough room to slip it in.

Thanks for your time F_R

Fish Magnet

 

[samo_ott]

Re: Replacing Throttle Control Gear 68 18hp Fastwin

Hmmm... You're talking about the vertical gear at the bottom of the throttle rod? It should come off as FR says. You shouldn't need to go crazy removing stuff... Of course my newest 18 is a '63 right now... Do you have a picture?

 

[Chinewalker]

Re: Replacing Throttle Control Gear 68 18hp Fastwin

Took me a bit to figure out what the issues was - it's the new gear that won't go in, because it is too tall with the intact bottom pin and it is hitting the lower cowling ? yes? I am pretty sure that you can loosen up the nuts that hold the belly pan in place to allow enough movement to give you clearance. You may also be able to use a j-bar to move the motor in its mounts enough to give you clearance, too. I've replaced quite a few and have never had to pull stuff apart to do it.

 

[Fish Magnet]

Re: Replacing Throttle Control Gear 68 18hp Fastwin

Thanks samo_ott and chinewalker. I think chinewalker understood my problem. I will try your suggestions. I didn't think there would be enough play in the motor mounts but I will give it a try. I'm sure glad I asked for help.