Drive Shaft Shimming Tool

[morebacon]

Duplicate

 

[morebacon]

I'm trying to measure the pinion gear height using the pinion gear shimming tool (91-56048). I cannot seem to get the tool to fit under the pinion gear like in the manual. It just sits at an angle and I cannot get an exact measurement with the feeler gauge.

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I guess because of the clutch dog? Is the propeller shaft supposed to be in when doing the measurement?

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[harringtondav]

Your pics didn't show. Doesn't matter. I assume you are talking about the pinion that drives the forward and reverse gears in the lower gear housing. Prop shaft gears. This shimming tool is used with the prop shaft assembly removed.

Also the lower pinion drive shaft + torqued-on pinion must be braced upward using the preload tools shown in the manual to get an accurate measurement. You also need to rotate the shaft at least two turns to get the bearing to seat.

Each of the Alpha shimming tools take finesse to get accurate measurements. The bearing bore pilots are a close fit, and you need to rotate the tool until you get the largest feeler gage to pass. Then calculate any shim adjustments from that feeler. Then recheck the whole thing after adjusting shims.

 

[morebacon]

That's weird! For me the pictures show just fine...

Yeah, I'm using the preload tool like in the manual to put upward pressure. I guess I got confused because the measurement tool has a hollow center. I thought that is so you could insert it through the propeller shaft, but after re-reading the manual it doesn't seem that is the case.

 

[morebacon]

Ok, so I took another look at this today. I've removed the propeller shaft and just kept the pinion gear and forward gear, per manual. I still cannot get the damn tool to slide until under the pinion gear.

The case seems to have just a slight "bump", which I'm thinking the tool cannot clear, but seems like it was machined like that, so not sure that is the real reason.

Any idea what I'm doing wrong? I also have the Seloc manual, which has a way to do the shimming without tools, but since I have them I'd like to do it properly. I just feel kind of stupid I cannot figure out the problem

 

[achris]

Is the tool genuine or aftermarket?

 

[morebacon]

From what I can tell it's the genuine one - 91-56048

 

[achris]

What model gear housing are you working on? MC1/R, MR/Alpha One or Alpha One Gen II? (Each has a different procedure)

Chris.........

 

[morebacon]

Working on a Alpha One Gen 2, service manual #14.

 

[achris]

Do you have the drive shaft preload tool in place?

 

[morebacon]

Yes, I have the tool in place - followed the Merc manual instructions (see first post pic). Shouldn't really matter though. The tool has enough room under the pinion gear, it's just the outer ring that doesn't slide through the case.

 

[achris]

If you're using a genuine tool, and the shaft preload tool, then it should go in. I've never had one not go in. The only thing I can think of is if the housing is distorted. Maybe try some grease on the outer edge of the shim tool.

Chris........