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Transmissions and Rear Ends Three on the tree or four in the floor? Shift it all here.

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  #1  
Old May 8th, 2016, 05:33 AM
surfamtn surfamtn is offline
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Default clutch help for a dummy

Hello gang,
So I need some help with my 1966 305E four speed.
I was driving around town yesterday, truck was running great and it was a beautiful day, as I took off from a stop light and shifting from second to third the clutch suddenly stopped working. it took me a minute to figure out what was happening, at first I thought I wasn't pushing the clutch all the way to the floor, then I thought it was just missing the gear with a stick. Eventually realized that pushing the clutch pedal wasn't doing anything to the clutch itself. Engine running running fine, I was able to coax (slam) it into gear and continue driving but at the next gear change I was unable to shift normally still.
The pedal still goes all the way to the floor, it does feel like there is a little less resistance than typically. Previous to this one specific shifting event I had been driving around town all day with no problems, no difficult shifts, no slipping or loss of power.
It's been raining cats and dogs here over the last 2 days and I haven't been able to get under the truck to look and see if there is some count of linkage broken or anything. I was wondering if this is something that sounds obvious to anybody in the club, or something with somebody's experienced before.
I consider myself a very green and self taught mechanic, I'm pretty sure this is a mechanical clutch without hydraulic assist right?
It seems like something suddenly became disconnected or failed, it doesn't really feel to me like I suddenly wore through the entire clutch plate.

Ideas?
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  #2  
Old May 8th, 2016, 06:45 AM
AZKen AZKen is online now
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Default Re: clutch help for a dummy

You tell us. Does it have two lines going to the Master cylinder? If so, it's hydraulic. One is brake, one is clutch. In any case you probably know you have to have someone push pedal down and observe. Don't have to drive in the rain to do that. You already have the right ideas in mind. You will soon see what part of the action is broken, loose, leaking or fluid low/air in line.....and hopefully not worse than that. In one case there is a slave cylinder (piston) which operates the clutch fork and the other is all mechanical linkage operating the fork.
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Old May 8th, 2016, 07:26 AM
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Default Re: clutch help for a dummy

Quote:
Originally Posted by AZKen View Post
You tell us. Does it have two lines going to the Master cylinder? If so, it's hydraulic. One is brake, one is clutch. In one case there is a slave cylinder (piston) which operates the clutch fork and the other is all mechanical linkage operating the fork.
From the factory, 1960 to 1963 trucks had hydraulic clutches. The 1964 and newer trucks had mechanical linkage for their clutches.
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Old May 8th, 2016, 07:51 AM
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Default Re: clutch help for a dummy

I love this forum!

Helpful replys at midnight!

From looking down through the engine bay: What I seem to be looking at is a mechanical linkage into the clutch body, it seems like the linkage is operating a cylinder that sticks out on the driver side, that cylinder rotates when the linkage is pressed.
At least I think, AZ Ken is right and need to have somebody depressed about a while I'm under the truck.

I'll let you know what I find just after breakfast tomorrow
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Old May 8th, 2016, 03:46 PM
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Default Re: clutch help for a dummy

If it is mechanical, I am willing to bet it is something with the linkage, clutch fork, or throw out bearing. Also remove the bell housing cover plate, then have someone engage the clutch while you are looking up at the exposed clutch assembly. You should be able to diagnose it fairly easily.
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Old May 8th, 2016, 07:50 PM
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Default Re: clutch help for a dummy

As Ed points out, you should have mechanical. That is usually on the drivers side. Most of the time there is a "Z bar" or "bell crank". (cylinder you mention). Pedal rod rotates bell crank which pushes clutch fork rearward and it pivots on it's pivot ball and pushes release bearing forward against clutch fingers to disengage clutch. As KChampagne says, should be easy to observe what is broken, missing, disconnected, worn out. There will be a big ol' return spring down there also.
What is a little unclear is that I think you are saying it only happened once and then it was normal again in other gear changes. That leads me to believe that all the "linkage" is present and operating . This could be a transmission problem. Also check to see if you have all clutch fingers present... if you can see in there. Hopefully, if you do have a flywheel cover, there is nothing laying in the bottom of it.
You are not a dummy. Dummies don't ask for help.

Last edited by AZKen; May 8th, 2016 at 08:38 PM.
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Old May 9th, 2016, 01:50 PM
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Default Re: clutch help for a dummy

Ok...

My reference to rain is that the truck is parked in the driveway since this event when I limped home. That made me laugh.

Ken: it happens suddenly during one shift but the clutch still won't disengage and thus I still can get it to shift. (Other than truning off the engine and coaxing it in to gear) so no... It wasn't just one time, it's still that way. I think what it was trying to to say is that it wasn't a gradual development like you'd expect with a worn clutch plate.
I got under there yesterday and I am sure it's mechanical. I'm in the middle of a kitchen remodel and didn't have time to pull the bell housing, but all the external linkage seems fine. There is an old repair job to the linkage that seems to be holding up well actually.
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Old June 14th, 2016, 04:37 AM
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Default Re: clutch help for a dummy

Pulled the clutch today... Problem is a broken bolt that holds spring tension on one of the three fingers.

Ordered a cluch from Adavance on the "new clutch thread" and doesn't fit, exactly as kchampagne warned. Still looking for the right kit but I have diagnosed the problem!.

Thanks!
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Old June 14th, 2016, 04:30 PM
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Default Re: clutch help for a dummy

Glad you found the fix, hope your able to get the right clutch.
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Old June 14th, 2016, 09:10 PM
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Default Re: clutch help for a dummy

Sorry about the clutch problem. I can't change the post anymore, but I reported it to Jeannie so she can fix it. The Amazon link posted says they still have 1 in stock.

Good luck!
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