Thickness of shims?

[AGENT 37]

Can anybody able to tell me the thickness of the shims A, B, C, & D for the reverse gear on a 2001 BF90 lower unit. Part numbers are 90538-ZW1-B00, 90539-ZW1-B00, 90540-ZW1-B00, & 90541-ZW1-B00........ Trying to get rid of the fore/aft play in the propshaft after installing new clutch, reverse gear, and bearings. I have almost 1/8" travel and there was no shim between the old gear and bearing. Thanks.

 

[JUSTINTIME]

Re: Thickness of shims?

a .10
b .15
c .30
d .50mm

 

[AGENT 37]

Re: Thickness of shims?

Thanks for those measurements.

I ordered and received shims C and D. I was expecting thicker. The unit originally did not have any shim for the reverse gear.

I replaced the reverse gear, clutch shifter, roller bearing, and thrust bearing because all were damaged. The replacements all measured the same as the originals. I assembled the unit and noticed the prop shaft was able to move in and out a little by hand and the shift shaft turned when I did it. Is this supposed to happen?

I do not remember how it was before the original thrust bearing failed and messed up the clutch engagement with the reverse gear. But it makes sense to me that the shaft might be designed to move aft to let the prop free wheel if the motor stalled or was suddenly decelerated rather than loading up the dragging prop's spin onto the drive shaft and up to the power head.

This is my first lower unit repair so I am lacking a little confidence. According to my repair manual I have all the required components in the correct position. One thing that I noticed is that the boats.net parts diagram shows the reverse gear shim between the roller bearing and the reverse gear which makes no sense and would have the shim do nothing. I think that the manual is accurate in showing the shim inside of the bearing carrier between the roller bearing and the aluminum carrier.

From what I gather, there is either supposed to be the thrust bearing or a thrust washer between the reverse gear and the prop shaft/ shift slider depending on HP and no application that uses both.

Any useful feedback would be great. Can somebody check their unit to see if the prop has fore/aft play? I don't want to go tear up this unit running it if something is not right. Thanks.

 

[AGENT 37]

Re: Thickness of shims?

It's a honda built 90 hp lower unit by the way. About a 2001 model.

 

[AGENT 37]

Re: Thickness of shims?

I must have left my prop shaft at our local shop and accidentally brought home a different one after having the mechanic show me how to remove it. My original prop won't even go on this shaft. And if I pull and turn on the shaft with it assembled into the gear case it engages the gear without detenting the shift slider. 90/115/150 use different props right? Those were the different parts that were laying around when we pulled the shift shaft and prop shaft.