jorgens

Hi all

When changing the motor in my 81` I accidently depressed the cluch when the slave cylinder was dismanteled. The piston was forced out, but reinstalled again. Now I`m having a big issue with the bleeding. I have forced fluid from the slave cylinder and up, used vacum on the reservoir, bled the system the "Normal" way, dismanteled the slave cylinder and pushed the piston back (2-3 minutes) then released slowly.
The cylinder operates, but not enough, I cannot put it in gear, it just makes the terrible grinding noise... Now I just gave up and had a beer

Ideas anyone?

Cheers
Jørgen

robot808

Jorgen,
If you look to the left of the Rennlist page, there is a DIY's section. If you click on that, it will reveal the 928 DIY's. Click on that and you will find several more methods of bleeding. You may have to try all of them, but with enough beer and patience, you will get it right.

jheis

You could try this method:


Are you sure that the intermediate pressure plate is adjusted correctly? If it's out of adjustment, it will definitely prevent you from getting it into gear.

James

Kevin in Atlanta

That is the method I used after someone did the same thing to my clutch slave - though I replaced the slave first.

Tom. M

I've found that once you "pop" the clutch slave....it can't be put back together and work ...I think the seals get scored/nicked and it allows air in at that point. If you can't seem to bleed the air out, you may need a new slave....

jorgens

As I`m pretty sure the big bogus is trapped air, I will try the Kempff Method first, as it sems plausible..



Jørgen

jorgens

Well, now I tried just about everything when it comes to bleeding, but still no sucsess.. Opened the master according to the "Kempff" method, bled the system several times (NO airbubbles) but still no disengaging.. the rod moves approx 15- 20 m.m. when I look at it through the inspection hole. So now I`m thinking of buying a new slave sylinder just to eliminate.

Intermediate pressure plate... I swapped the old 4,5 to a 4,7, and just bolted the cluch on.. everything from the 4,5 motor was used. Could it be it needs adjusting after doing this?


Jørgen

Jroman

I replaced clutch slave yesterday then flushed/bleed the system, then lastly I loosened the 2 bolts on the slave so that there were only a few threads holding it onto the housing and pumped the slave while the reservoir cap was off (about 20times). Clutch is working great now.

Tom. M

I don't remember the exact spec but that sounds about right (17mm?). If the slave is moving that much it should be more than enough to release the PP and the int. plate.

I would suggest doing the int. plate adjustment. If that is out of adjustment, your clutch discs will be dragging, keeping it from going into 1st or rev easily.

killav

I have had great success bleeding the clutch slave/master cylinder by using the BRAKE master cylinder as the "pump" instead of the oil can method shown in the video above. All you have to do is connect a rubber hose from the nearest brake bleeder nipple on your brake caliper, zip tie it on so it won't pop off. Connect the other end to the nipple on the slave cylinder and zip tie this end as well. Crack both of them open, and pump the brakes. That's it. It will pump all the air up and out the top of the brake fluid res.

Edit: See that you already replaced it. Glad its working now.

Kevin in Atlanta

Ever since i replaced my slave my shifting has been notchy. Sounds like you backed the slave off and drove the rod in and out of the slave several times while the slave nipple was open. Do I have that right?

Jroman

Slave nipple was closed....cap was off reservoir

Opelotus

Don't mean to steal this thread, but it brings up some interesting issues. My slave cylinder has been "popped" and reassembled twice (once when the original clutch failed catastrophically, and again when my assistant hit the pedal with no clutch installed.). But before that there were only about 100 miles on it. I have since learned to disconnect the pedal pushrod to prevent this when servicing. Anyways, I still cannot get the clutch to function properly (int. plate has been adjusted, etc), although I have yet to try the other suggested bleeding procedures. Would it be prudent to just replace the slave cylinder and then bleed?

jorgens

Now I`m pretty sure the rod has the correct travel lenth (17 m.m.) so onto the intermediate plate; Anyone that can give me a "walkthrough" about how to do the adjusting? Does the cluch need to be removed?

Any help appreciated!


Jørgen

Tom. M

You'll need to drop the lower bellhousing cover... but the clutch stays in. Here's a link to a search for "intermediate plate adjustment"... many many threads on how to do it.... https://rennlist.com/forums/search.php?searchid=9860999

Basically there are three adjusting tabs.. you'll rotate the engine to each one...set it (can't remember the spec but something like 1mm between the tab and the H)..rotate..and do all three.... Hardest part is actuating the clutch arm so you can check if the adjusment stays....