NEw clutch not adjusting correctly
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,254
Likes: 5
From: Brown Summit North Carolina
NEw clutch not adjusting correctly
I installed the 350 motor back into my 71 car last night and I have ran into a possible disaster, I am worried I may have to remove the motor.
I Installed a new ZOOM clutch. It is a basic upgrade from oem.
The old clutch had very little wear but I replaced since the motor was out.
The old set up had the adjusting nuts on the clutch rod about 2 to 3 inches from the end of the rod and about 1'" of free travel.
I have adjusted this new unit all the way to the end of the rod and I still have about 6 to inches of pedal free play before the pressure is felt.
I removed the boot and the fork is loose on the pivot ball.
When you mash the clutch a lot of the travel is being used to seat the fork dimple onto the ball, then the fork start to compress the fingers.
I have a fear that the pivot ball may be the issue. It is an OEM type.
I see that the allen head is accessable with the trans bolted to the bell hsg.
Is it possible to adjust or replace the pivot ball w/o removing the motor or trans?
It may also be something that someone that is more experienced with this couls fix easily. I am just freaking out that I may have to pull the motor back out.
Thanks
DAvid
I Installed a new ZOOM clutch. It is a basic upgrade from oem.
The old clutch had very little wear but I replaced since the motor was out.
The old set up had the adjusting nuts on the clutch rod about 2 to 3 inches from the end of the rod and about 1'" of free travel.
I have adjusted this new unit all the way to the end of the rod and I still have about 6 to inches of pedal free play before the pressure is felt.
I removed the boot and the fork is loose on the pivot ball.
When you mash the clutch a lot of the travel is being used to seat the fork dimple onto the ball, then the fork start to compress the fingers.
I have a fear that the pivot ball may be the issue. It is an OEM type.
I see that the allen head is accessable with the trans bolted to the bell hsg.
Is it possible to adjust or replace the pivot ball w/o removing the motor or trans?
It may also be something that someone that is more experienced with this couls fix easily. I am just freaking out that I may have to pull the motor back out.
Thanks
DAvid
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,254
Likes: 5
From: Brown Summit North Carolina
As for the throw out bearing. They look close. I will have to call Zoom to get a measurement and check for sure.
The old one measued the same thickness as the new one.
The fork is fully in the slot on the T/O bearing and the clip is behind the ball.
Its a mystery at this point.
Thanks for the assistance
David
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
All above good tips to check into ... in addition though is this:
flywheels get thinner with use, especially when resurfaced/ground ... as it thins, pp mount surface moves forward and pp fingers move forward and tob also moves forward. This is not some pie in the sky esoteric hypothesis; it's real.
one solution: correction shim(s) are placed between flywheel & crank flange ... the shim moves the fw rearward; all related clutchpak dimensions also move rearward.
Because of this ... ready-to-use fw shims are purposely mfd for this application by several companies including "Pioneer". FYI, "Perfection Clutch" is parent of Zoom; they manufacture flywheels too and may also offer fw shims.
flywheels get thinner with use, especially when resurfaced/ground ... as it thins, pp mount surface moves forward and pp fingers move forward and tob also moves forward. This is not some pie in the sky esoteric hypothesis; it's real.
one solution: correction shim(s) are placed between flywheel & crank flange ... the shim moves the fw rearward; all related clutchpak dimensions also move rearward.
Because of this ... ready-to-use fw shims are purposely mfd for this application by several companies including "Pioneer". FYI, "Perfection Clutch" is parent of Zoom; they manufacture flywheels too and may also offer fw shims.
Le Mans Master
Joined: May 2006
Posts: 5,814
Likes: 414
From: Pittsburgh suburbs Pa.
Pressure plates with high dome fingers take shorter throw out bearings and low dome fingers take long release bearings. They might have given you a short pressure plate with short bearing. If so , you will have to slide the trans back far enough to switch bearings.
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,254
Likes: 5
From: Brown Summit North Carolina
I called ZOOM. The 3006S clutch comes with a 1 1/4" height T/O bearing.
That matches to my old bearing removed.
Still chasing the problem
Thanks
David
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Melting Slicks
Joined: Sep 2007
Posts: 2,429
Likes: 0
From: Tucson AZ
Just a note: Think of how far the pedal travels in relation to the clutch fork. The pedal travels 6-9 in., depending on the pedal and the car? The clutch fork moves......as little as 3/8"? Not doing the math for you, but half of that travel at the pedal would equate to approx. 3/16", not alot of travel. It doesn't take a whole lot for the adjustment to be off, and would seem to be alot off.
Thread Starter
Drifting
Joined: Oct 2007
Posts: 1,254
Likes: 5
From: Brown Summit North Carolina
Just a note: Think of how far the pedal travels in relation to the clutch fork. The pedal travels 6-9 in., depending on the pedal and the car? The clutch fork moves......as little as 3/8"? Not doing the math for you, but half of that travel at the pedal would equate to approx. 3/16", not alot of travel. It doesn't take a whole lot for the adjustment to be off, and would seem to be alot off.
I was not aware that this spring helps keep the fork seated on the pivot ball.
A new one should be here tomorrow and I will try again. Also odered a new boot.
Man I hope this turne out to be a simple rookie oversight on the importance of this spring.
Thanks
David