I have CKC = clutch kit confusion! (1 Viewer)

[vtcruiser60]

Well its not exactly a catchy title...but thanks for looking....

I am rather confused on which clutch kit to purchase. I have a 71 F motor in a mainly 74 FJ40. I am in the process of doing some tcase work and would like to replace the clutch while I am in there. I definitely have a 4spd transmission.

When looking at the clutch plate last evening, I have a triangular, 3 finger plate.....which I thought was only consistent with 3spd transmissions. For example, when looking at the coolcruisers.com website, that three fingered clutch plate is only listed for 3 spd trannys.

I am confused and need some direction on which clutch pressure plate, disc, bearings I am need.

 

[grant5127]

'74 was a transition year that had 4 spd. trans w/3 spd. clutch components........
Just order the 3spd stuff, you'll be fine........

 

[vtcruiser60]

'74 was a transition year that had 4 spd. trans w/3 spd. clutch components........
Just order the 3spd stuff, you'll be fine........

Good to know...thank you...that clarifies.

 

[3_puppies]

either kit (3 or 4 speed) works with either trans as long as you use the correct kit for the flywheel you have.
3 or 4 speeds kits just need to be on their respective flywheel

 

[Fuzzy Logic]

either kit (3 or 4 speed) works with either trans as long as you use the correct kit for the flywheel you have.
3 or 4 speeds kits just need to be on their respective flywheel

What about the t/o bearing & fork differences?

 

[bsmith123]

finger vs diaphragm clutch

https://forum.ih8mud.com/40-55-series-tech/245021-pics-oem-p-ns-rear-main-clutch-change.html

I laid out the finger style and diaphragm style parts for comparison in the post

The diaphragm clutch is supposed to be an upgrade and I put in a 79 2f and tranny/transfer so I went with that, since that was what the 79s used----but, look how well the old design worked so ???? Just do what suits you. For a whole clutch change out to diaphragm style with all new OEM parts including a rear main seal It cost around $400. With the F I might stick with the finger style and just buy what I actually needed.


In my post I have all the parts and part numbers for the diaphragn clutch system (OEM from CDAN) I got all the pieces new except the flywheel which came with the motor so I just had that turned


As someone will point out sooner or later it is not 3 speed vs 4 speed it is finger vs diaphragm style clutch ---the latter is a more modern design

The trick is to keep all finger style stuff together or all diaphragm stuff and don't mix parts between the two. Even the fork pivot is different but you can see it all in the post

 

[vtcruiser60]

https://forum.ih8mud.com/40-55-series-tech/245021-pics-oem-p-ns-rear-main-clutch-change.html

I laid out the finger style and diaphragm style parts for comparison in the post

The diaphragm clutch is supposed to be an upgrade and I put in a 79 2f and tranny/transfer so I went with that, since that was what the 79s used----but, look how well the old design worked so ???? Just do what suits you. For a whole clutch change out to diaphragm style with all new OEM parts including a rear main seal It cost around $400. With the F I might stick with the finger style and just buy what I actually needed.


In my post I have all the parts and part numbers for the diaphragn clutch system (OEM from CDAN) I got all the pieces new except the flywheel which came with the motor so I just had that turned


As someone will point out sooner or later it is not 3 speed vs 4 speed it is finger vs diaphragm style clutch ---the latter is a more modern design

The trick is to keep all finger style stuff together or all diaphragm stuff and don't mix parts between the two. Even the fork pivot is different but you can see it all in the post

I forgot about your old thread. I have been looking for a picture of that rear main seal install tool....pvc. Thanks for reposting.

I will stick with the three finger.....IF I CAN FIND ANOTHER ONE FOR A REASONABLE PRICE....negative at any of the online parts stores...I can't get a LUK number.....anyone have any leads?

 

[donny paradise]

Flywheel

Some desire the 3spd flywheel for its heavier weight, = more torque

 

[vtcruiser60]

Some desire the 3spd flywheel for its heavier weight, = more torque

Mark (marks offroad) had some sage advice on this very point in his FAQ's

070-CLUTCH

a.3 SPEEDvs. 4 SPEED [3 finger vs diaphram] (DD?) The 7/74 and older FJs came with a large recessed stepped flywheel and a 3 finger type pressure plate. The 8/74 and newer came with a diaphram type. When people are looking at swapping in newer motors and/or trannies, they often wonder about changing the clutch setup as well.

Why? Well if you have had a problem with clutch chatter with a 3 finger pressure plate, you probably heard somewhere along the way about how much smoother the diaphram pressure plate is. This is undeniable. So why would anyone stay with the older clutch then? Because if you don't spend a lot of time shifting, and you do spend a fair amount of time off road, you will appreciate the fact that the heavier flywheel of the older clutch type will keep the motor spinning at lower rpm than the newer one will [i.e. it's harder to stall!]

If slippage is a concern, I have found rebuilders who were willing to install heavier coils into the 3 finger pressure plate. All you can do to the diaphram pressure plate in this regard is add plate weights like Centerforce uses, which do not really start to apply their extra pressure until much higher rpms, not usually where you're running your cruiser for longevity's sake.

Bottom line: I'm not advocating taking out a diaphram setup if it's already in your rig. But if you've got one, think for yourself before ditching it based on a rumor that the grass is greener on the other side.

 

[Fuzzy Logic]

3spd chatter, eliminated

grant5127 posted info awhile back on adjusting (bench test) finger height before the actual install to eliminate the uneven t/o bearing contact that causes the chatter.

I followed that advise and mine is smooth as silk

I'll search for the post or maybe he'll chime in

 

[bsmith123]

adjustment

I think I saw that adjustment in the FSM have to check later on