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Clutch fork throw measurement *fixed*

mr250twostroke

mr250twostroke

1/2 ton status
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Can I talk someone with a hydro clutch into measuring the throw of their fork for me? Mine is 3/4". A buddy of mine measured his mechanical and got 1" but his clutch disengages @ about half pedal. Seems like I should be in range with mine... I have only installed my Ranger OD to verify clutch disengagement before putting the tranny in. Made this-

to see if its working, no luck wont spin or budge. Wtf, im spittin pissed atm...





Putting the tranny back in my 87 Suburban and before I do so... I am looking for others opinions on CF vs. stock clutch. I have both in excellent condition but have heard from more than 1 person they weren't happy with the CF and preferred stock. Other variable the stocker is a 3 finger pressure plate. My clutch is hydro so I dont believe 3 finger matters over diaphragm. The Burbs main duty - towing, not a dd.

IMAG0127.jpg
 
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Iv used the Dual Friction one, made the pedal a lil stiff, and your not supposed to slip it Iv heard, dunno why just what i heard, but it held up great for years behind a built 350 in an old pickup on 40s I had
 
Not that it really helps matters much, but I've got a Sachs diaphram clutch in mine (10 years now) that I've had no problems with. I don't tow much with it, at best 2000lbs very infrequently.

How much weight are you talking about towing? I'll have to ask my Dad what he ended up putting in his, he is running a 454 and has been towing a 3000lb travel trailer for a bit. I think his truck scaled somewhere around 6000lbs. I'll get clarification.

To be fair to the three finger setup, the pedal assembly was so worn out, I never got a chance to compare it to the diaphram in proper working order. He was towing a 10,000lb trailer with that one though, don't think he ever had a problem with it.
 
IMO... A CF isn't worth it. The main selling feature is the weighted pressure plate - the hard you spin it the tighter it clamps. This seems backwards for our application as the majority of use is probably well under 4k rpm, either wheeling or towing. How does it help in a low rPm application??

When I bought a clutch for my k5 I had the local clutch builder get me a strong pressure plate from a 1 ton and then build me a ceramic disc.
 
dyeager535 said:
Not that it really helps matters much, but I've got a Sachs diaphram clutch in mine (10 years now) that I've had no problems with. I don't tow much with it, at best 2000lbs very infrequently.

How much weight are you talking about towing? I'll have to ask my Dad what he ended up putting in his, he is running a 454 and has been towing a 3000lb travel trailer for a bit. I think his truck scaled somewhere around 6000lbs. I'll get clarification.

To be fair to the three finger setup, the pedal assembly was so worn out, I never got a chance to compare it to the diaphram in proper working order. He was towing a 10,000lb trailer with that one though, don't think he ever had a problem with it.
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Thanks Dorian. 10K trailer/Blazer (6500k ish)/ocassional Suburban. Basically stock 350, 465 w/27% overdrive, 5.13's and 38's... 1 tons, lockers etc.
I am curious about experience with the 3 finger, always had a diaphragm. My guess is a mechanical pedal would make the noticeable difference between my clutches?
 
nvrenuf said:
IMO... A CF isn't worth it. The main selling feature is the weighted pressure plate - the hard you spin it the tighter it clamps. This seems backwards for our application as the majority of use is probably well under 4k rpm, either wheeling or towing. How does it help in a low rPm application??

When I bought a clutch for my k5 I had the local clutch builder get me a strong pressure plate from a 1 ton and then build me a ceramic disc.
Click to expand...

This is the train of thought iv'e gathered. I really dont want to buy a new clutch when I have these 2 but... I want happiness and have no desire to drop this tranny for along time. This rig gets little use so when I do load up it just needs to work as best it can.
 
Well I always blamed his clutch feel on the mechanical vs. hydraulic difference from driving mine. But after removing his pedal and finding as much wear as it had, the three finger was not the issue.

As his truck is now I don't notice the clutch at all, but I'll let you know when he responds what he is running.
 
dyeager535 said:
Well I always blamed his clutch feel on the mechanical vs. hydraulic difference from driving mine. But after removing his pedal and finding as much wear as it had, the three finger was not the issue.

As his truck is now I don't notice the clutch at all, but I'll let you know when he responds what he is running.
Click to expand...

Thank you! One other question... I cant find any difference on T O bearings between 3 finger and diaphragm clutches, guessing they use the same? I have 2 new ones that were definitely a diaphragm application. Again, would like to run what I brung if possible.
 
Actually the wife wants another Nova, possibly a Chevelle (I like em both) and I have a fresh 396 (which the C F came off of) so... just need to verify this 3 finger stocker will work for me. The C F will just go back where it belongs.
 
From what we came up with last time, GM part number 15590168 was used in 1988 for the TO bearing, but GM doesn't break the clutches down by what they are...all the motors had a different clutch part number, but they don't give the style.

I don't know how you'd even know...maybe if a Chevy dealer could give you the part number from a 1973 truck with 465, see if it was changed to 15590168.
 
dyeager535 said:
From what we came up with last time, GM part number 15590168 was used in 1988 for the TO bearing, but GM doesn't break the clutches down by what they are...all the motors had a different clutch part number, but they don't give the style.

I don't know how you'd even know...maybe if a Chevy dealer could give you the part number from a 1973 truck with 465, see if it was changed to 15590168.
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Yup' I believe you've helped me with this before :doah: Actually Shane (leadfoot067) works for Strange Transmission and came up with the same. In it goes, i'll report back :D
 
sweetk30 said:
some 3 finger can hit hydro clutch fork . . ask me how i know this :doah:
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?

Ok, had some unexpected company side track me... back on it. In this pic -

IMAG0128.jpg


The circumference of my T O bearing barely hits all 3 fingers, the slightest nudge will make it fall off one of them. looks like the diameter needs to be bigger to work? Anyone know what it should look like?
 
There is also a 1/4" difference in height between the 2 different styles, the 3 finger being further from the flywheel. There MUST be a different T O bearing between the 2... :dunno:
 
Its been a while since I bought mine but I'm certain there was a difference between manual and hydraulic.

I also found a lot of talk about which style would and wouldn't work with hydro. Ultimately I didn't want to chance pulling the doubler back out so I bought a diaphragm style.
 
sweetk30 said:
search hydro and my screen name. have a thread with pics on 3 finger problem.
Click to expand...

Yep, read your thread awhile back. Forgot where you said no 3 finger with hydro though :doah:
I have both types of bell housing's so i'll save the 3 finger for the mechanical.

IMAG0131.jpg


IMAG0130.jpg
 
Dustin, we've talked about this also a few years ago. I would NEVER run a CF because it applies more force the faster it spins which means that it is also pushing harder on the thrust bearing of the engine and they've been known to wipe out the bearing and cost an engine rebuild. For towing you want a "full load" pressure plate, this means there is a spring in every location. Most pressure plates only have about 75% of the max possible springs. The more springs it has the more claming force there is on the clutch disc but it's also harder to puch in the clutch (a moot point though when running hydro clutch).
 
4X4HIGH said:
Dustin, we've talked about this also a few years ago. I would NEVER run a CF because it applies more force the faster it spins which means that it is also pushing harder on the thrust bearing of the engine and they've been known to wipe out the bearing and cost an engine rebuild. For towing you want a "full load" pressure plate, this means there is a spring in every location. Most pressure plates only have about 75% of the max possible springs. The more springs it has the more claming force there is on the clutch disc but it's also harder to puch in the clutch (a moot point though when running hydro clutch).
Click to expand...

Scott your the main reason for my post, I take what you say seriously ALWAYS!
On another note I'm sorry I missed you while you were up here. My mother inlaw passed away suddenly (57 yrs old :() and my focus changed immediately. I coming down the 6th to spread my grandmothers ashes on 17 mile drive on the 8th, would dig catching lunch or something with you. Having said that, what clutch specifically would you recommend for my application?
 
I haven't read the thread but I do have a centerforce dual friction in the blazer and it seems to be a decent clutch.

I also stayed at a Holiday Inn express last night.:D
 
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