Yamaha Backlash Indicator

[kzmako1996]

Looking for some help with the backlash indicator YB-6265. Ant seem to find one. Anyone have a measurement of the distance to the mark on the indicator?

[boscoe99]

Any Yamaha dealer can get you the part that you need. Or you can contact the Yamaha tool supply house, K & L Tools.

But are you sure that you have the correct tool number?

[kzmako1996]

Yes. According the tech manual that is the tool. Looks like it’s a simple hose clamp with a tab mounted to it. The measurement

[kzmako1996]

is dependent on the distance from the shaft. Just looking for the distance to measure from the OD of the shaft for proper backlash measurement.

[panasonic]

Unless someone on here has that actual tool to take the measurement from then you will probably have to get the Yamaha tool.
Although it is a really simple tool, the distance from the centerline of where it clamps on the driveshaft to the mark where the dial indicator touches it is critical to get a proper measurement of the backlash.

However having said that, I would think that the mark on tool would be Half the diameter of the pinion gear as measured from the center line of the driveshaft. In other words...if you could see the pinion gear through the side of the gearbox (xray vison) the mark on the tool would be lined up with the outer edge of the pinion gear.

Don't quote me on that...because I don't know for sure. I would get the tool.

[boscoe99]

What is the model of the motor please? In a number of cases the YB prefix part numbers have been changed to a different format part number.

[boscoe99]

Unless someone on here has that actual tool to take the measurement from then you will probably have to get the Yamaha tool.
Although it is a really simple tool, the distance from the centerline of where it clamps on the driveshaft to the mark where the dial indicator touches it is critical to get a proper measurement of the backlash.

However having said that, I would think that the mark on tool would be Half the diameter of the pinion gear as measured from the center line of the driveshaft. In other words...if you could see the pinion gear through the side of the gearbox (xray vison) the mark on the tool would be lined up with the outer edge of the pinion gear.

Don't quote me on that...because I don't know for sure. I would get the tool.

You have got me pondering my navel. Thanks.

[kzmako1996]

Motor is 1993 200TXRR.

[boscoe99]

Yamaha and their parts/tools numbers are enough to cause a saint to drink. Tool number is YB-06265.

Also known as part number 90890-06706.

The Yamaha tool supplier is K & L Tools. This site, boats.net, should be able to get you the backlash indicator. Just give them a call.
zblash.jpg

[boscoe99]

Unless someone on here has that actual tool to take the measurement from then you will probably have to get the Yamaha tool.
Although it is a really simple tool, the distance from the centerline of where it clamps on the driveshaft to the mark where the dial indicator touches it is critical to get a proper measurement of the backlash.

However having said that, I would think that the mark on tool would be Half the diameter of the pinion gear as measured from the center line of the driveshaft. In other words...if you could see the pinion gear through the side of the gearbox (xray vison) the mark on the tool would be lined up with the outer edge of the pinion gear.

Don't quote me on that...because I don't know for sure. I would get the tool.

I am now thinking that Yamaha (and other motor makers) have factored into the backlash amount that is to be seen on the gauge in order to get the correct amount of back lash between the gear teeth. Based on the dial indicator point being some distance outward from the gear teeth. Does this make sense?
zblg.jpg

[TownsendsFJR1300]

Does this help?

[panasonic]

I am now thinking that Yamaha (and other motor makers) have factored into the backlash amount that is to be seen on the gauge in order to get the correct amount of back lash between the gear teeth. Based on the dial indicator point being some distance outward from the gear teeth. Does this make sense?
zblg.jpg

Yes that is exactly what I was trying to describe. Seeing that you can't get at the actual gears to put the dial indicator on we have to use the driveshaft to measure off. So that little tool that clamps on to the driveshaft is needed. The line on the tool gives the correct distance from the center line of the driveshaft to measure from and it is critical to put the dial indicator tip right on the line.

If you measure out past the line you will end up with a false reading that will be to large. And if you are inside the line, closer to the driveshaft you will end up with a false reading that is small.

Just looking at the diagrams in the manual, which look somewhat to scale, the line on the tool "looks" like it would be lined up with the outer edge of the pinion gear.

But we can't go by what we think looks right on gear lash measurements, we have to be sure it's correct, so the proper tool is required in this case. The math/geometry was already done for us by the Yamaha engineers.

[panasonic]

I have to pull my prop shaft out of my 20hp this spring to replace a bearing. I will measure the pinion gear diameter for fun, make a little tool up like the one in question and see if I can get correct backlash reading using the pinion diameter to put the reference line on the tool.

I know I don't have to fool wit the backlash adjustments to just change out a needle bearing...just do it for an experiment. Someone will read this and say "why are you measuring backlash for a bearing change" I know they will...lol

[boscoe99]

I have to pull my prop shaft out of my 20hp this spring to replace a bearing. I will measure the pinion gear diameter for fun, make a little tool up like the one in question and see if I can get correct backlash reading using the pinion diameter to put the reference line on the tool.

I know I don't have to fool wit the backlash adjustments to just change out a needle bearing...just do it for an experiment. Someone will read this and say "why are you measuring backlash for a bearing change" I know they will...lol

Why are you measuring backlash for a bearing change?

[kzmako1996]

Took me a while to make the decision but I ordered the tool. $49!!! I have the lower gear disassembled. I’ll attach the pinion gear to the Input shaft along with the backlash gauge clamped on. I’ll take some measurements and I’ll let everyone know what I find.