Thrust Question

pjdeb

Senior Member
Hello,

I reassembling my 26/27 Model T transmission, once I drive the clutch basket down onto the key in the shaft, and bottom out the retaining bolt into the shaft, I find that I have very little clearance.

It is probably only .005 . The book calls for .015 - .027.

1. Has anyone tried sanding down one of the three thrust washers?
2. Is it better to turn something off the mating surface on the downside of the basket?
3. Is this dimension that critical in the first place?

Thanks in advance.
 
Are you supporting the main shaft from underneath ? I use an extra driven gear - ithe teeth fit perfect between the 2 dowels. Yes, that gap is critical for expansion.
 
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The engine is vertical on the stand. The flywheel, triple gears, and drums are all in place. The three thrust washers are in place, When driving the clutch basket down on the key, and then running in the square head bolt into the shaft, I end up with no clearance.

Book says I should be able to move the drums up and down .015-.027. Only solution I can see is to take material off the underside of the clutch basket where it mates with the thrust washers. Or reduce the combined thickness of the three thrust washers. Each is .042 thick. I would have thought vendors would sell a thrust washer of varying thickness, but I do not see that offered from anyone.
 
Have you replaced any parts or they all original to that transmission ?

Perhaps contact Steven at Lang's to discuss the washer issue.
 
There is a 3320BW washer that is .025" in thickness. It is used for conversion on earlier type units when the later style bushing is used. They are used with two 3320D washers in that application.

I think several model T parts sources have them. I don't know why the Op has a tight clearance there but I would also be curious as to how many parts are OEM for the 26/27 transmission assembly. There has been a lot of water under the bridge for any old model T.
 
Wow! Thanks for the info on the washer. The coupe is a 1923, but is has been fitted with the wider brake drum of the 26/27. The drum has the inserts covering the tabs where the outer clutch discs slot. The key does not contact the three thrust washers. There is plenty of play between the bottom of the key and the three thrust washers before driving on the basket..

All that play goes away when I drive the clutch basket down on the shaft. I have tried not driving it down all the way, but the the square headed retaining bolt will not run all the way down into the hole in the shaft.

The clutch basket is Ford. It is the type with the six holes in the web, so it should accept the .025 washer. Lang's sells it.

I have no idea why there is no clearance when using the three standard .042 thrust washers.

Thanks again.
 
As long as it has the 26/27 case then it should be OK. If all bushings and pieces parts are properly seated then you either need the thinner washer or take one of the .042" washers to a machine shop and get it surface ground. There is no way I can tell you why all the .042" washers are too much without inspecting all the piece parts for proper dimensions.
 
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