Stuck Clutch.

[Z320]

Hi Jamie,

yes, you need to buy and fit a new lip seal.

As long the channel is long enough to cover the gap in the clip and „half hole“ in the gb all is OK.

In your case to me it looks like some grinding could be done.

The shaft would be better with locating groove but it is also located by the fork and release bearing carrier.

The grease nipple…..my 4A didn’t have them, I fitted them but they are not easy to grease.

Please have a look: does the new cover have a 3 mm (?) hole in the „tube“ in the 18:00 position?

Ciao, Marco

[RogerH]

Hi Jamie

 your shaft is as a TR6.  It can float sideways if needs be - that is not a problem.

 

Roger

[My Dads Car]

5 hours ago, Z320 said:

yes, you need to buy and fit a new lip seal.

Hi Marco - purchased from Rimmer yesterday. What I paid in shipping to the US (no domestic sources had one) for the lip seal and gasket was an eye opener....

5 hours ago, Z320 said:

Please have a look: does the new cover have a 3 mm (?) hole in the „tube“ in the 18:00 position?

 

Yes, it does have a small hole. 

4 hours ago, RogerH said:

 your shaft is as a TR6.  It can float sideways if needs be - that is not a problem.

 

Thank you, Roger

 

[stuart]

Couldnt you get the seal from BPNW? https://bpnorthwest.com/drivetrain-axles-bearings/seal-transmission-front-tr3-to-tr6/

Stuart.

Edited September 4 by stuart

[My Dads Car]

On 9/4/2026 at 7:34 AM, stuart said:

Couldnt you get the seal from BPNW? https://bpnorthwest.com/drivetrain-axles-bearings/seal-transmission-front-tr3-to-tr6/

Stuart.

Grrrr….. I forget about BPNW. Thanks for the reminder. 

On the reconstruction front I have a question regarding the new pin: shouldn’t it pass through the entire shaft? I can only get it to go up to the opposite end of the shaft before it is too tight. This applies to when it is turned with the threaded fork attached. 

When I test fit the pin in the fork only, it fits perfectly and threads almost to the top of the pin. 

Overall, I’m missing about 1/8” of travel when I mock up the fork to the shaft. 

-Jamie 

[John Morrison]

I wouldn't use a bolt fitted at 90 to the tapered pin, for me its to big a hole and

you are adding weakness, I always do it this way, with a 4mm roll pin - never failed 

either pin or pin!!

John.

[Z320]

Found this photos about the groove

 

[Ralph Whitaker]

6 minutes ago, Z320 said:

Found this photos about the groove

 

Well spotted Marco. The drain groove in Jamies new part definately needs to be ground out further or as your picture shows the oil will not drain out of the void. On Jamies new one the slot doesn`t even extend beyond the circlip groove.

Ralph

[My Dads Car]

5 hours ago, John Morrison said:

I wouldn't use a bolt fitted at 90 to the tapered pin, for me its to big a hole and

you are adding weakness, I always do it this way, with a 4mm roll pin - never failed 

either pin or pin!!

John.

Hi John- first of all, apologies for hijacking your thread! I believe your setup is akin to how the accelerator pedal is held in place. I will definitely give it some thought as an option. I do like that this approach does not introduce and nuts that can loosen over time and cause future headaches!

 

4 hours ago, Ralph Whitaker said:

Well spotted Marco. The drain groove in Jamies new part definately needs to be ground out further or as your picture shows the oil will not drain out of the void. On Jamies new one the slot doesn`t even extend beyond the circlip groove.

Ralph

Thank you Ralph and Marco. Given my inexperience with grinding Stuart’s suggestion of just cutting the old nose to size seems to a better option for me…

Here are two more photos regarding my tapered pin question:

Above is the total length of the threaded portion of the pin = 3/8”

This is as far as I can tighten the pin when connected to the shaft - only 1/8” of thread is used. This can’t be sufficient- right? I read the Buckeye Triumph section on this, and while it does say the original design did not have the back end of the pin extend into the fork my current situation seems a bit extreme….

- Jamie

 

[Lebro]

I tend to agree  I would want more threads than that to be inside the fork. If you have access to a lathe you could take a little off the tapered part, not much would be needed. Or with a pillar drill maybe ? Only a tiny amount need be removed to allow the pin to go in further.

Bob

[My Dads Car]

47 minutes ago, Lebro said:

I tend to agree  I would want more threads than that to be inside the fork. If you have access to a lathe you could take a little off the tapered part, not much would be needed. Or with a pillar drill maybe ? Only a tiny amount need be removed to allow the pin to go in further.

Bob

Thanks for the reply. No access to either of those tools…. Would a hand reamer on the shaft be to blunt an object to increase hole diameter? 

-Jamie

[Dale Moore]

You have got the taper in the hole running the right way ? The pin should go right through , putting two sections of the pin in shear 

Dale 

[My Dads Car]

2 minutes ago, Dale  Moore said:

You have got the taper in the hole running the right way ? The pin should go right through , putting two sections of the pin in shear 

Dale 

Hi Dale- there’s only one way the pin fits through the cross shaft. When I try to push the pin in the cross shaft I can’t get it all the way through, even without the fork attached. 

[Dale Moore]

Yes that's true The other way would put the slave cylinder operating lever at the top Have you tried the pin the other way to see if the hole is indeed tapered  ?  A tapered hand reamer otherwise,  just to get the pin just through the shaft The pin needs pulling up to nearly the end of the thread Say just one thread remaining when it's tight 

[My Dads Car]

7 minutes ago, Dale  Moore said:

Yes that's true The other way would put the slave cylinder operating lever at the top Have you tried the pin the other way to see if the hole is indeed tapered  ?  A tapered hand reamer otherwise,  just to get the pin just through the shaft The pin needs pulling up to nearly the end of the thread Say just one thread remaining when it's tight 

Yes, I can’t insert the pin at all from the opposite direction, so definitely tapered. 

[BlueTR3A-5EKT]

Drill a hole up through the top of the fork, while it’s in bits, so you can punch the bit of broken pin out in the future.

[Ralph Whitaker]

Probably a stupid question, but is that new pin tapered, it doesn`t look it from the photo, and with the state of current re-pro parts it wouldn`t surprise me if it isn`t. I seem to remember that mine was a lot more obviously tapered.

Ralph

[Lebro]

It is a very shallow taper, & marks on it show how far it entered the shaft hole.

Perhaps some carefull fileing around it wwould let it in abit further.

Bob

Edited September 7 by Lebro

[BlueTR3A-5EKT]

Even if the pin goes in further it is still in single shear.  The end of the pin should be supported where it exits the shaft in a hole the same size as its diameter.  
 

Hence the benefit of cross drilling and adding another pin/ bolt to mechanically support for the taper pin’s inadequacies 

[My Dads Car]

All - what are your thoughts on throw out bearings in this photo?

The one on the left is what i pulled out of the car. It looks to be in good shape to my eyes ….. or I could use the Koyo I’ve had sitting around for a bunch of years- I’d have to press that on a steel sleeve. 
 

I have read the Koyo squeals a bit at engagement and can do a number on the diaphragm fingers but does offer improved performance.

Thanks for any and all responses!

-Jamie 

[RogerH]

Hi Jamie

the bearings look fine but it is not the visual assessment that is required. 
If you spin the old bearing what does it sound like.   It should be a smooth whirrrrrrring.   No lumps, bumps or clicks - it must be smooth.
If you hold the outer diameter of the bearing and gently rotate the inner diameter what does it feel like.   Again, no lumps, bumps or clicks.
There should be no restrictions to spinning.

You may neeed to clean the oil/grease out of the bearing to do the above.

Regarding the taper pin.
Ideally you need more threads inserted.  Unless you have the correct taper reamer then there is no point in improving matters , as you simply will not improve things.    As stated above, the pin is in single shear. In other words only one side of the pin is supported.
If the Male/Female tapers were perfect then single shear is more than adequate.  Sadly they are not perfect by a long way. 
So realisticly the pin is not even in single shear. As a load is introduced the odd point contacts try to bend the pin so you end up with a tensile failure.

The additional pin set at 90' to the taper pin is a very good modification - and it works.  This is the preferred mod'.
Or you could fit a bush inside the fork  in the cavity above the taper pin for the pin to sit in double shear.  It is not easy but I have done it once and it works. 

Roger

[My Dads Car]

All - a huge thank you for helping me figure this out. Gearbox is installed working great, better than I remember, even! Switches gears like a dream and no untoward noises, even when engaging reverse (there was alaways at least some grinding going into reverse no matter how many adjustments I made)

While the initial culprit was not a stuck clutch but a wrongly installed friction plate, the necessary pulling of the gearbox brought my latent clutch fork problems to my attention... A fortunate circumstance in the long run and an opportunity to learn a great deal from you all

Again, thank you for taking the time to respond to my questions. I hope this thread is of assistance to someone else in the coming years.

Now, onto seats...!

-Jamie