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Help. I think my transmission is on it's way out.

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Old 10-19-2009 | 07:02 PM
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Default Help. I think my transmission is on it's way out.

It's started about 3 months ago. It grinds a little almost evertime I shift into 2nd unless I'm real careful. Also if I don't shift into neutral I can't get it out of gear once the car stops at a light and don't want to force it so I have to clutch start in 3rd and 4th sometimes. Does this sound like synchro's?
Old 10-19-2009 | 07:07 PM
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Sounds like the clutch isn't disengaging. Continuing to drive like this is what wears out the synchro's.

Could be a few different things from hydraulics to something failed in the clutch pack. Any recent clutch work? Made any changes to the brakes that would have involved bleeding brake fluid?

Master / slave could be waving goodbye, any record of those getting changed? Pull the floormat, look for fluid coming out of the master. Even if dry, the seals on could be leaking internally. I recently had a brake master that was doing this.
IIRC there are specs in the WSM for how far the slave rod should move, use the inspection hole on the lower bellhousing to measure. If all that checks out might be time to pull the clutch pack see what broke.


I had a strange issue a few years ago. The clutch was intermittently disengaging. After changing all hydraulics (and bleeding about five different times), pilot bearing, both frictions discs, three different intermediate discs, and clutch shaft...... I discovered the guide tooth on the release bearing ring broke off allowing it to float around.
Old 10-19-2009 | 08:38 PM
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Could be hydralics as Hacker says! BUT, sounds very much like intermediate plate adjustment, especially if the clutch pedal feels normal. pretty easy to check. just remove the bell housing and check the 3 gaps of the intermediate plate adjusters (H adjusters). or cut a hole like I did in the lower bell housing.
But, if it only does it in 2nd gear , and its a grind, and you CAN still get the car in to 1st at a stop light when you previously were in neutral, then its probably clutch actuation system stuff. In otherwords, if you are stopped and in neutral, and you put the clutch in and slowly put the shifter in 1st gear without a grind, and it goes in, interemediate plate is probably adjusted close to ok. If you cant get it in gear, no mater how long you wait with the clutch in , its the intermediate plate adjustment or the hydralics are just not moving the clutch enough.
Old 10-19-2009 | 08:44 PM
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Originally Posted by mark kibort
Could be hydralics as Hacker says! BUT, sounds very much like intermediate plate adjustment, especially if the clutch pedal feels normal. pretty easy to check. just remove the bell housing and check the 3 gaps of the intermediate plate adjusters (H adjusters). or cut a hole like I did in the lower bell housing.
Clutch needs to be disengaged to test the adjusters, not that easy since you need to find a way to pull the arm all the way back. Some people use some kind of ratcheting strap.
I didn't feel this was very safe so I have a 2nd bellhousing with a hole cut in it.

https://rennlist.com/forums/928-foru...ch-owners.html

Before you go through that much work, test the hydraulic movement. That is what the inspection hole below the clutch slave is for.
Old 10-19-2009 | 09:17 PM
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The first item to check is the plastic cup on the top of the clutch fork, make sure it hasn't crumbled to dust. It is relatively easy just pull the airbox, the arm should be attached to a ball there and you should be able to see if the cup is still there or if it is history.

On my 82 the housing bent on my throw out bearing and wouldn't disengage the clutches. Might be worth while to pull the clutch pack clean everything inspect for wear and make sure the intermediate shaft is lubed properly, use what the manual calls for bearing grease is WAY to thick.
Old 10-19-2009 | 09:20 PM
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Originally Posted by nosnow
The first item to check is the plastic cup on the top of the clutch fork, make sure it hasn't crumbled to dust. It is relatively easy just pull the airbox, the arm should be attached to a ball there and you should be able to see if the cup is still there or if it is history.

On my 82 the housing bent on my throw out bearing and wouldn't disengage the clutches. Might be worth while to pull the clutch pack clean everything inspect for wear and make sure the intermediate shaft is lubed properly, use what the manual calls for bearing grease is WAY to thick.
It's always the simple things we forget to mention.

On Rick Carter's car, the plastic cup was still in place over the ball. His problem is the ball unscrewed itself from the upper bellhousing. That was an entertaining fix in a field.
Old 10-19-2009 | 09:40 PM
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Hey Mr Mid-Atlantic region ITB champion, it sounds like the clutch as stated above. In addition to what has been said, there are tons of threads about Hacker's and my dual disc clutch issues.
Old 10-19-2009 | 09:40 PM
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good point. after you check hydralic movement, just check the gap on the intermediate plate (i.e. less than 1mm), that will tell you most of what you need to see anyway.

mk

Originally Posted by Hacker-Pschorr
Clutch needs to be disengaged to test the adjusters, not that easy since you need to find a way to pull the arm all the way back. Some people use some kind of ratcheting strap.
I didn't feel this was very safe so I have a 2nd bellhousing with a hole cut in it.

https://rennlist.com/forums/928-foru...ch-owners.html

Before you go through that much work, test the hydraulic movement. That is what the inspection hole below the clutch slave is for.
Old 10-20-2009 | 12:45 PM
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Originally Posted by FlyingDog
Hey Mr Mid-Atlantic region ITB champion, it sounds like the clutch as stated above. In addition to what has been said, there are tons of threads about Hacker's and my dual disc clutch issues.
Hey Matt! Good to hear from you and thanks, it was a tough season but it ended great with a track record too. We are heading down to the ARRC in atlanta to battle it out in the ITB car. Whens your 928 going to be in GT or ITE?

Sounds like I have a few things to check out. I also noticed with the clutch in, the car will roll just a tiny bit unless your on the brakes so I'm leaning toward the disengaging theory.
Old 10-20-2009 | 01:31 PM
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Originally Posted by chewy8000
Sounds like I have a few things to check out. I also noticed with the clutch in, the car will roll just a tiny bit unless your on the brakes so I'm leaning toward the disengaging theory.
That's 100% proof that the clutch is dragging / not disengaging all the way.

Dan
'91 928GT S/C 475hp/460lb.ft
Old 10-20-2009 | 04:08 PM
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Originally Posted by chewy8000
Hey Matt! Good to hear from you and thanks, it was a tough season but it ended great with a track record too. We are heading down to the ARRC in atlanta to battle it out in the ITB car. Whens your 928 going to be in GT or ITE?
I'm thinking about racing the Mustang in the NASA-SE event at Road Atlanta in December. I've never been there but it sounds like a ton of fun.

My project is going nowhere fast since I just had to move out of my home in Herndon. I'm hoping I'll get a new place, get a ton of work done over the winter, and can race the 928 in GTS3/4 next year. Either that or I'll just sell it with the 81 US, Jeep, and Mustangs...
Old 12-12-2009 | 11:03 PM
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[QUOTE=nosnow;7000410]The first item to check is the plastic cup on the top of the clutch fork, make sure it hasn't crumbled to dust. It is relatively easy just pull the airbox, the arm should be attached to a ball there and you should be able to see if the cup is still there or if it is history.QUOTE]

I think the problem has been solved this was all that was left of my plastic cup bushing I replaced it with a new one.

Old 12-12-2009 | 11:23 PM
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I'd still check intermediate plate adjustment. It's worth getting that right so you get complete disengagement. Mine had exactly the same symptoms and had a shot bushing, and the intermediate plate wasn't releasing the rear disc totally, because it wasn't centered. If the clutch has never had that adjustment that you know of .. chances are it might need it.




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