Model B Clutch Fork Assembly - Couple of Questions

mr.precision · Apr 19, 2014

I removed the clutch fork assembly from my 1950 Model B in order to determine the source of slop in the clutch lever. The factory manual is vague about the following:
1. Is there a replaceable bushing in the housing that the splined shaft passes through?
2. Is some play in the shaft/fork splines normal? Is this area to be greased on re-assembly (seems a light coat of grease would be correct)?
3. The manual says to pour 1/2 quart of motor oil behind the "dam" on the inner clutch pulley housing cover. I cannot see any trace of oil there (it wasn't removed) and looking at the parts book, I don't see how oil could get in there when the motor oil is changed. If there is no oil there, should I just pour 1/2 quart behind the dam anyway?

I am enjoying work on this old girl, but am amazed how vague some of the instructions are in the factory shop manual.

Thanks in advance-
Mike

Anonymous-0 · Apr 19, 2014

When I rebuilt the fork assembly on my A, I took the splined shaft out, had it welded up and turned down back to its original diameter at a machine shop, then had a bushing made to put into the shaft housing so it all fit snug with no play other than enough for it to move, there will be wear on the splines, id say if all of the splines are showing even wear and not to the point where you feel you can move the fork cradle side to side on them it should be ok, not sure about the oiling part

pbb · Apr 19, 2014

You could weld it and machine it down if it was bad. Mine
wasn't real bad so I got some brass shim stock and cut it to fit .
I rolled it up to make it curved and cut off enough to take the
slack out both the pulley brake and the fork housing. I have a
model A so I bought 9/16 pins and a new lever bolt and
bushing. I done mine 3 years ago and it's still no slop.

mr.precision · Apr 19, 2014

Thanks for the ideas.
With regards to the oil "sump" located below the 1st reduction gear, I think I figured it out. There is a mysterious filler plug located just behind the engine oil filler cap. It's not mentioned in the shop manual. It clearly accesses the first reduction gear area, and looks to be the proper place to add oil to the area behind the cover. So I added 1/2 quart of engine oil, as specified in the shop manual (when the cover has been removed). My guess is the old oil leaked out over the years. The gears in there are bone dry. So we'll see what happens.
I did put a light coat of grease on the splines, which seemed the right thing to do.

RandyB(MI) · Apr 19, 2014

The clutch fork verticle shaft new od is .998-1.000 and the bore in the "housing" you refer to is 1.060 - 1.065. That is 65 thousandths of slop when brand new. Twice the width of a spark plug gap. Tighten up all the pins and clevises ( new pins and overbores) and new main pivot pin/bushing and it will be as tight as new and work just fine. They were never "tight". Measure your shaft/bore. Mine was .994 / 1.067, left it alone and did all the other and it is snug and works just perfectly. There's a reason they left that much slop and I think it has something to do with the brake pad being able to lie flat on the pulley when new and also when almost worn out. The slop allows the pad (which travels in an ark) to lie flat whether full thickness or 1/16' thick equally.

Model B Clutch Fork Assembly - Couple of Questions

mr.precision

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Anonymous-0

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pbb

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mr.precision

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RandyB(MI)

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