1971 type 911/01 clutch fork tool

[jpnovak]

If anyone has tried to mate a 1970-1971 type 911/01 transmission to the engine you know it can be difficult to properly seat the clutch fork to the throwout bearing. for those who do not know, the 70-71 clutch assembly uses a throwout bearing and clutch fork that must mate by rotating the TOB 90 degrees while engaging the fork to reinforced tabs on the TOB. It is nearly impossible to engage both tines of the clutch fork and rotate the TOB. Usually the clutch fork will want to pivot on its mounting stud so that you can only get one side engaged.

I just wanted to share my simple tool to make this effortless.

The factory manual says to release the tension on the pressure plate and then engage the clutch fork. How exactly is this done? I am glad you asked...

First, mate the tranny bell housing to the engine case making sure to have the two slots on the throwout bearing align with the tines on the clutch fork. If you have one of these systems you know what I am talking about. Next, rotate the crank until one of three threaded studs appear. These will be located at 120 degree increments around the perimeter of the pressure plate. They will be located midpoint between the PP mounting bolts. These holes can be accessed through the starter mounting hole on the bell housing.

the tool is relatively simple. I used a section of copper pipe. Dimensions are 1/2" OD and it has a thin wall. I used a 8.8 allen head cap screw, a nut for a spacer and two washers to make sure the allen head screw stayed outside the section of copper pipe. The pipe was approximately 12mm long.





Usage is simple. place the section of pipe over the spring tension release stud. Then insert the capscrew through a washer and thread into the release stud. When you tighten the cap screw it will place pressure on the copper pipe section and "lift" the release stud. This pulls the pressure plate forward. Don't expect a lot, it will only move 2-3mm. Insert one, rotate the crank 120 Deg and then install the second. Repeat until all three are installed. Here is a picture of the location and tool installed prior to tightening.



Once the third one is in place you can pull forward on the clutch fork and use a screwdriver to rotate the TOB and engage the clutch fork. Then simply remove the three tools.

Voila! you are done in about 10 minutes.

[fastfredracing]

That is a great idea. I did have problems with the first one I did, however, I just engage the throwout bearing onto the fork as I am sliding the transmission onto the motor. Have done this at least 6 or seven times now without any trouble whatsoever. I think my method would be quite a bit more difficult if you were trying to install the motor, with the transmission still in the car though.

[jpnovak]

Fred, This particular clutch setup does not allow for assembly while mating. It is very different than any 915 setup or the early push-type clutch.

I agree that a 915 is easy to mate with the motor.

[Rumble-Bee]

I just went through this on my 70 911T. I used bronze bushings but they didn't work because they crushed (like your copper tubing did). ddinham gave me the right idea: he told me to use wing-nuts. Those were perfect because they not only did not crush or give but you could see the "rivet" pull out as the bolt tightened. The wing nut should be just large enough thread diameter so that the bolt slips through easliy.

[JerryL]

GD you have PM, looking for some guidence as to this method.

Regards