Clutch pressure ring

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Stephen_heatherly
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* REQUIRED* Type and Year of Model Ts owned: 26 coupe and 23 Runabout
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Clutch pressure ring

Post by Stephen_heatherly » Sun Jan 13, 2019 4:39 pm

So, I removed the engine from my 26 coupe to find the source of a slight engine knock. In the process I took my transmission apart to install some better triple gears to make the transmission a little quieter and to install a new wide brake drum. I discovered that the holes in my driven plate where the pins for the clutch pressure ring stick out are slopped out a fair amount. While it's not really a big deal and will doubtless work fine I'd like to reduce the play some. I have no idea how it happened. They were not worn before and I assembled the clutch correctly the last time the engine was out so the pressure ring was not taking any torque from the clutch. Being a 26 transmission it has the pressure ring with the smaller pins. My question is, do you see any reason why I could not simply install an earlier pressure ring with the bigger pins to reduce the play? Other than the diameter of the pins being different, the two styles of pressure rings appear to be identical. It may be necessary to slightly enlarge the holes a bit more for the larger pins to fit, but that's a minor issue.

Thank you,
Stephen


Wayne Sheldon
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Re: Clutch pressure ring

Post by Wayne Sheldon » Sun Jan 13, 2019 7:00 pm

I think it should work. However, be careful fitting the holes. They tend to wear on one side more than the other, and sometimes they wear in a odd direction. you need to carefully examine the driven plate to determine the direction of wear, and carefully file to recenter. Once centered, careful drilling with the appropriate drill size should make a nice finish.
As I said, I "think" it should work. I considered doing that some years ago, and looked at the problem, seeing no reason not to do so. But then I found I had a better piece and used that instead. So I didn't actually do so.


Topic author
Stephen_heatherly
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Joined: Wed Jan 09, 2019 6:03 pm
First Name: Stephen
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Re: Clutch pressure ring

Post by Stephen_heatherly » Sun Jan 13, 2019 7:43 pm

The holes appear to be worn evenly in both directions, so I think a drill bit should clean them up enough for the earlier ring. I'll have to check it out more tomorrow after work.

Stephen


Dan McEachern
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Re: Clutch pressure ring

Post by Dan McEachern » Sun Jan 13, 2019 11:24 pm

The cause of the worn out holes in the driven plate is that someone assembled the transmission with a small disk as the last one in the stack. This causes the pressure plate to act just like a large disc, except the 3 pins are now reacting the torque rather than 6 notches in the brake drum. Always count your discs before you load them- 13 large, 12 small and make sure the last one in is a large one.


Topic author
Stephen_heatherly
Posts: 386
Joined: Wed Jan 09, 2019 6:03 pm
First Name: Stephen
Last Name: Heatherly
* REQUIRED* Type and Year of Model Ts owned: 26 coupe and 23 Runabout
Location: St. Louis MO

Re: Clutch pressure ring

Post by Stephen_heatherly » Sun Jan 13, 2019 11:46 pm

Dan, I assembled the clutch myself. When I did so the holes were not worn and I assembled the clutch properly with a large disc on top. That's why I'm puzzled as to how this happened in the first place.

Stephen


Adam
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Re: Clutch pressure ring

Post by Adam » Mon Jan 14, 2019 9:27 am

I’ve taken apart many transmissions that have had wallowed out holes in the drive plate and all of them had the correct large clutch disc against the push ring. It seems to be as common with the early and late style transmissions.
By the nature of the design of these parts, the push ring is locked up tight and does not move any time the vehicle is running in high gear. Any time the vehicle is running in low, reverse, or neutral, the push ring is loose in the holes (has no spring pressure on it as the load of the clutch spring is not pressing against it). At these times, it is free to slop around in the holes and easily can. I think the wallowed out holes are characteristic of a T that sees a lot of time idling and running in low gear.


Mindless Automaton
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Re: Clutch pressure ring

Post by Mindless Automaton » Mon Jan 14, 2019 10:43 am

Or you could cut some copper pipe & push it in the holes, then swedge the ends over so it doesn't fall out.

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