Force 85 throttle/ shift linkage adjustment

[Homebrew72]

Learned a hard lesson today. I tried adjusting my shift/ throttle cables and well ended up rocketing my boat up a concrete ramp. I optested it at home first. Seemed to be working fine. Put it in the water started it in neutral which was more like WOT. Up the ramp and out of the water I went. The reason why I was messing with the cables was the control itself was very hard, like you had to force it to throttle up/down. It worked but was messing up the back side of the control. Can someone please point me in the right direction.

 

[Homebrew72]

I don't know if its the right terminology or not but the "tower shaft" vertical bar that the carb linkage attaches to is very hard to move even with the cables and linkages disconnected. what would cause this? I cant see any thing wrong with it.

 

[SkiDad]

it could be at the top of the timing tower the small plastic block has split - that happened to my dad on one outing - couldn't get it to idle down.

 

[Jiggz]

With the control cable disconnected and the tower shaft is still hard to move, only a couple things can make this possible. The most likely cause is a stuck or dirty trigger advance plate. And the other will be the carb's throttle linkage. However, for the throttle linkage you can test this easily by just trying to move the tie bar that connects all three carb throttles and it should be easy to move. If it does, then the problem is with the advance linkage starting from the top of the tower shaft and all the way to the trigger advance plate. Accessing the trigger plate requires flywheel removal and also messing with the engine timing. Thus, if you decide to go this route you will need to set the timing again. For now, you can try disconnecting the control cable and also the link rod (connecting the tower shaft to the cam) and play with the tower shaft to see if it will loosen. Blow in some air to see if it will clear it. If not then you will need to remove flywheel.

 

[Homebrew72]

Thanks for that. Carb linkage moves easy so I guess I'll be removing the flywheel. Any secrets to removing the flywheel? Thanks for the help.

 

[Jiggz]

Try loosening up the towershaft first by repeatedly moving it back and forth to see if does. If not then remove the flywheel to get access to trigger plate. The best way to do it is to use an impact wrench while at the same time using something to jam the flywheel gear to a stationary part of the engine. Above the top carb there should be a place to jam the gear to keep if from rotating. Other have used the three bolt holes to hold it in place by bolting in a long steel handle with matching holes. Others used longer eye bolts on these holes and used pipe to hold it. And of course, nothing beats penetrating oil for preliminary. Just make sure if you use the impact wrench that the engine has no way of starting . . . kill switch activated and all plug wires disconnected.

 

[Homebrew72]

Do I need a puller to get the flywheel off?

 

[Homebrew72]

So I couldn't get the fly wheel off because the puller I have doesn't have the right bolts. I cycled the tower shaft multipal times and lubed it up with some WD. The tower shaft will not return to idle position when using the throttle control, I have to put it in neutral then manually push the tower shaft back to neutral. does it matter if the motor is running or not?

 

[Jiggz]

Yes, you will need a puller or gear puller to pull the flywheel off. With the control throttle connected, the tower shaft should move with the cable. If the cable moves, i.e. from neutral to WOT but the towershaft doesn't then it means the problem is with the control throttle and not with the towershaft. On the same token, with the control throttle at WOT position and moved back to neutral the towershaft should move with it. If not then there is a problem with the control throttle. If this is the case, then you need to check the control lever instead of the towershaft.

On the otherhand, if the control throttle or lever is hard to move when connected to the towershaft but loosens up when disconnected from the towershaft, then the problem is with the towershaft.

 

[Homebrew72]

With the cables disconnected the control handle moves easily. With the cables connected the handle is stiff, the tower shaft will go to WOT. When I put it back in neutral the tower shaft only returns 3/4 of the way.

 

[Jiggz]

As for troubleshooting the control throttle itself, you would have to wait for the admirals to chime in. While waiting you might want to backstep what kind of adjustments you made earlier to put it back to its original configuration. The tower shaft's neutral position can be visually ascertain with the position of the cam and the carb throttles The same is true with the WOT position wherein the throttles will be in full horizontal position with reference to the carb's body.