15 HP Force Shifting rod problems

rellish

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Jan 9, 2014
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1
My buddy has a 15hp force that we don't know the year of, we are guessing pretty old. It wasn't pumping water and was overheating so we replaced the impeller no problem. When we went to put the lower unit back on we could not get it to shift to neutral or reverse, it gets stuck in forward. We have tried pulling the rod out into neutral and putting everything back together but when we go push the lower unit completely back on there is too big of a gap. Any help would be appreciated we are trying to get in a weekend duck hunt or two and really need the motor to run.
 

Frank Acampora

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Jan 19, 2007
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12,004
Re: 15 HP Force Shifting rod problems

Since you need room to screw together the upper and lower shift rods, you pull up the lower shift rod as far as you can. There is a cam in the lower unit and this detent is forward gear. You move the shift lever on the engine to reverse giving you full downward extension of the shift rod. Now you assemble the lower unit onto the engine leaving the gap to connect the two shift rods. After connecting the shift rods, push the lower unit all the way up and tighten the four mounting bolts. This will either move the shift lever, move the lower shift rod, or both. However, the engine should shift correctly.

Since the deepest detent on the cam is on the bottom, to come up into neutral or reverse requires a bit of force to overcome spring pressure that keeps the drive dogs engaged with forward gear. Thus, you should feel some resistance when pushing up the lower unit to tighten the bolts. Some of these engines are really fussy though. The shift linkage is long with a couple of bends and it would rather flex than shift. be certain all pivot points are well lubricated.

The lower shift rod screws into the cam and if you unscrewed it, it must be screwed back in. Usually it is screwed in as far as it will go, but it can be screwed out a bit to regulate shift lever movement.
 

Nordin

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Jun 12, 2010
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2,428
Re: 15 HP Force Shifting rod problems

The shiftrod lower screws into the cam as Frank says.
This is the right adjustment for the lower rod.
When you shift the lower unit into neutral the center of the hole in the rod should be 3/16 +- (puls/minus) 3/64 in below top mounting Surface.
If not screw it up or down.
 

oldboat1

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Apr 3, 2002
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9,598
Re: 15 HP Force Shifting rod problems

If your motor has the horizontal shift lever on lower front of the pan, I would be interested in finding out what direction is forward (left or right), and what lever position (forward or reverse) lowers the upper shift rod.

To correctly position the upper and lower shift rods so you can reattach them, use the engine gear shift lever to drop the upper rod (whatever that setting is -- either forward or reverse.) Raise the lower shift rod in the lower unit by pulling it up (whatever gear that engages in the lower unit). As Frank A. says, raise the lower unit to the point where it is held in place by the bolts, but there is still enough room to screw the shift rods together -- then fully raise the lower unit into place after reattaching the shift rods. A way to make reattaching the partially attached lower unit easier is to raise the shift rod with the gear shift lever on the engine, while lifting the lower unit up to its flush position, then tightening the bolts. I'm not sure whether that will mean shifting into forward or reverse (which relates to my first question). But with the lower unit in place, you should be able to shift gears properly. You may have to turn the prop slightly while shifting into gear, but this would be normal. Unless you removed the lower shift rod or screwed it up or down into the cam in the gear box, the shift should be just as it was before you dropped the lower unit to get at the water pump. Try turning the prop slightly or pulling the starter cord slightly when trying to shift and see if that makes a difference.
 
Last edited:

Markster

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Apr 14, 2014
Messages
8
Re: 15 HP Force Shifting rod problems

I realize this post is a couple months old, but it contained the info that i really needed to repair my nephews gamefisher 15hp. I figured it was time to add what i learned while repairing it so its clear for the next guy.
On this little engine, which is identical to the force 15, while looking at the front of the engine, at the controls, sliding the horizontal shift lever to the left engages reverse, sliding it to the right engages forward. Center is neutral. By sliding the shift lever into reverse, the cam in the bottom end is forced down, causing the clutch dog to move towards the prop engaging the reverse gear. If you can't engage reverse its likely that the rod is not being pushed down far enough to reach the detent in the cam. Pulling the bottom end off and turning the lower shift rod until it matches the specs given above should correct the problem.

I'm a First time poster. I hope this info helps someone out.
 

oldboat1

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Apr 3, 2002
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9,598
Re: 15 HP Force Shifting rod problems

Thanks for the post, Markster. It's OK to post info like that as a new thread (in fact, maybe want to go ahead and do that just for grins). Can allude to a prior post for context, if that works. (BTW -- not all Chrysler lower units work the same way in terms of that lower shift rod and cam.)
 
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