912 Engine Conversion

[Brett Voigt]

I have a 1969 912 that came with an early 70's VW 1600 DP engine in it. I recently sold that engine and bought a proper 68' 912 engine that bolted right up to the 901 trans (as expected). The engine was from a guy we found who had a 912 that ended up getting totaled 20 or so years ago. He kept the engine with the plan to put it in a kit car. Regardless, that plan never played out but he maintained the engine well and when we just started it up this weekend, it runs properly and needs a few little things to make it pur. In hindsight, we should have changed out the clutch while the engine was out of the car, but the excitement of fitting the right engine back into the car overshadowed that thought. When pressing the clutch and shifting into any gear, there is a lot of grinding and it never engages (ftw the car drove without issue with the VW engine). We did change out the bearings of the shifter, put in a new clutch cable, and changed out the bearings and clutch spring of the pedal cluster. At this point I think we need to pull the engine and put in a new clutch and pressure plate. I found the Sachs kit here on Pelican and it seems like a reasonable price. All that in mind, is there anything that we will need to change out with the 901 transmission that may have been changed or modified to accommodate the VW engine?

[bobrestore]

have you checked to be sure you got ALL of the slack out of the clutch cable? Does the peddle depression actually move the actuating arm significantly.... bob

[Brett Voigt]

Pressing down on the pedal does move the actuating arm, so I think the issue is further down the line. I should add, that just before we took the VW engine out, the pedal cluster broke. We welded it back together, replaced all the bushings as well as the clutch pedal spring.

[WFBowen]

Brett:
It's not uncommon for clutch discs to freeze-up when not used for long periods of time. Sometimes it's stuck to the flywheel, sometimes to the pressure plate and sometimes onto the input shaft (or any combination of these.) While it's best to just put in a new kit, you might get lucky by dropping the motor away from the trans and free-up the parts.
Bill

[Brett Voigt]

Originally Posted by WFBowen

Brett:
It's not uncommon for clutch discs to freeze-up when not used for long periods of time. Sometimes it's stuck to the flywheel, sometimes to the pressure plate and sometimes onto the input shaft (or any combination of these.) While it's best to just put in a new kit, you might get lucky by dropping the motor away from the trans and free-up the parts.
Bill

We talked with the PO and while he had no issues with it before the car was totalled, he never needed to do any clutch work for the entirety of his ownership, and may be the original clutch from 68'. We also talked with my grandfathe'rs Porsche mechanic who thinks it's the throwout bearing. That all in mind we ended up buying the Sachs kit late last night. My goal at this point is reliability, plus the kit seems like a good deal and should give 10-15 years of good driving. When we take the old clutch apart I'll see whats all stuck together.

[NICE 69 S]

If the flywheel looks questionable at all, I would pull it and have it resurfaced. No use spending all that money and time to just bolt the new clutch to a questionable flywheel. Replace the rear seal also.
Bob B

[Brett Voigt]

My dad and grandpa took it apart today without me. They said the main issue was the bearing to the shift fork was blown. Also the throw-out bearing was questionable. The clutch had about 40% wear but wasn't showing the splines yet. Flywheel looks good. Basically going to change out everything but the flywheel.

[Brett Voigt]

So they pulled the engine, installed the new clutch and went to install the new shift fork bearing, but it wouldn't fit. On further exam, it looks like the prior owner had some issues too and tried to modify/weld it. Either way, we found a new (used) one and it should be coming this week. Everything will be new except for the flywheel, so hopefully that shift fork was the issue and I can get to driving it this spring.

[Brett Voigt]

Another update. Everything was put in, but it still didn't work. We looked over everything and after comparing it to another 901 trans that my grandfather has, we noticed that the shift fork looks a bit different. Turns out the PO put in a 70-71' 911/01 trans. We think it has to do with the whole push/pull clutch thing. Now reading up on all that. Not sure what we'll do yet to fix it yet. I guess I'm most disappointed that it's not the original numbers matching transmission.

[bobrestore]

Bret.... You said the arm moved when the peddle was pressed... While you have the peddle fully depressed have some one under the car see if the clutch arm will move further..... the adjustment "nut" on the cable usually has a large shimming collar so that all the slack can be adjusted out... bob

[upwardr]

If they changed it to a push type setup there is a plastic "T"pc that does the pushing and also I believe the clutch cable is fastened at the engine to allow the cable to push.
I could be wrong though.