Got prop carrier out 90hp tower part question

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stevehendo34

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So after I pulled the shaft and all out the cam follower on the end of the shaft after the clutch dog fell out.
Manual says something about 3 small balls used for bearings under the cam follower.
Is this true, wish I had part number, merc dealers parts guys are dumb as doorknobs.
If you had one apart maybe you could just tell me if there supposed to be three small balls ,between cam follower and drive shaft @ inner end.

Cam Sift Type II lower unit
 
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Texasmark

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Inside the front end of the prop shaft is the cam follower....a slightly pointed copper tube that protrudes out the end of the shaft and engages the detents of the shifter cam which is mounted via splined shifter shaft to the front of the inside of the LU housing, then a button that adapts the copper tube to a spring, then the spring, and then 3 balls. Somewhere in all that (I forgot; through the follower as I recall) a pin goes through the slot in prop shaft to hold the clutch dog (the sliding gizmo with saw teeth on the front end and cogs on the rear) in place and then a spring wraps around the dog to hold the pin in so it won't fall out. The detents in the cam cause the cam follower to be positioned at a different point along the length of the prop shaft....F is most forward position, N is mid position, and R is all the way back into the prop shaft and in doing so the dog's teeth/cogs engage or don't engage the respective gear teeth/cogs.

My guess is that on the original design, the spring Merc engineers selected was too sloppy in compression to work correctly and not knowing how much was enough they figured that the quickest way to solve the problem was to add a SS ball which caused the spring to compress somewhat and see if that made for enough force...nope so they added a second compressing it more.....nope so they added a third.....yep, and to this day that series LU still had the 3 balls. Why? Because they had a cheap solution to the problem and didn't have to diddle around with spring tensions to find the right answer....they already had a solution. Otherwise what the .....is the point for having 3 1!@#$$%% balls in the stupid thing.
 
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Faztbullet

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If you had one apart maybe you could just tell me if there supposed to be three small balls ,between cam follower and drive shaft @ inner end.
If the end of your cam follower(pointed pin) is flat it does not have the balls,if it has a concave groove it uses the balls....

My guess is that on the original design, the spring Merc engineers selected was too sloppy in compression to work correctly and not knowing how much was enough they figured that the quickest way to solve the problem was to add a SS ball which caused the spring to compress somewhat and see if that made for enough force...nope so they added a second compressing it more.....nope so they added a third.....yep, and to this day that series LU still had the 3 balls. Why? Because they had a cheap solution to the problem and didn't have to diddle around with spring tensions to find the right answer....they already had a solution. Otherwise what the .....is the point for having 3 1!@#$$%% balls in the stupid thing.

That guess is wayyy off as the new and old cam follower are same length...the cam follower was changed to reduce wear on the cam and follower by using the balls as a bearing. This allows the front portion of cam follower to remain stationary and the propshaft and rear slide to spin. This reduces wear in the cam groove and wear on cam point. The older followers the cam and point on follower will wear down and cause reverse shifting problems as clutch dog is not push back far enough...
 

Texasmark

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So the balls were bearings? Why 3? Why didn't the LU oil provide lube for the cam follower to prevent erosion? What was the time line and hp range for the changeover if you know it?

Thanks,
Mark
 

Faztbullet

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So the balls were bearings? Why 3
3 balls have more load contact than a single ball...
Why didn't the LU oil provide lube for the cam follower to prevent erosion?
Wasn't erosion it was wear.....
What was the time line and hp range for the changeover if you know it?
Somewhere around 1982 is when the kit came out and was all the inlines 75 hp and up....There is a TSB out on it, I had all the TSB's from 70's -94 but they where burnt up in a fire...
 

Texasmark

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3 balls have more load contact than a single ball...

Wasn't erosion it was wear.....

Somewhere around 1982 is when the kit came out and was all the inlines 75 hp and up....There is a TSB out on it, I had all the TSB's from 70's -94 but they where burnt up in a fire...

Hmm. Okaye Thanks I no longer have my 2002 90 nor my SM so I can't see what it had, just for the record.
 

owenie

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Wow! so happy to have found this forum. I discovered the 3 ball bearings on the ground and have been scratching my head since. I can see them in the parts list called up a cam follower kit but couldn't find out where they sat. So is it as simple as just dropping them in and then sitting the cam in?
thanks
Owen
 

GA_Boater

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Wow! so happy to have found this forum. I discovered the 3 ball bearings on the ground and have been scratching my head since. I can see them in the parts list called up a cam follower kit but couldn't find out where they sat. So is it as simple as just dropping them in and then sitting the cam in?
thanks
Owen

Start a new thread. This is 4 years old. Thanks.

Closed.
 
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