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Old 07-17-2005, 12:45 PM   #1
Lobo'74
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Clutch Bad? :confused:

OK, I thought my 3 speed manual was bad, but sorta thought the clutch needed adjustment as it was starting to slip under heavy throttle. No clutch smell, but after a heavy throttle shift it takes a second before the transmission catches up to the engine.

Went into my Chilton's, and my Chevy Chassis Manual this morning to see how to adjust the clutch. When I looked at the mechanical linkage it looked like it was adjusted all the way out already. I took off the clutch return springs (PO put two on it) from the fork lever. Then I tried to adjust the end of the clutch rod at the forward end, next to the cross shaft lever (Chilton's calls it the lever and shaft assy). There were only about 4 threads showing on the clutch rod already, so there was nothing left to adjust to start with. Also, the 9/16" nuts are blocked out by the cross shaft lever and the headers so it would have been VERY difficult to reach had there been any adjustment left.

Next I went backwards to the fitting at the end of the clutch rod that mates to the end of the clutch fork lever. I was able to move that further out by about 1/4" (maybe). I then put more gear lube into the transmission (filled it at the side port until it started to drip out. It was low, but NOT anywhere near dry.

I reattached the two return springs (Why did PO put 2 on there? ? ? Its stiff !) and started it up. Previously I could NOT force it into reverse but could get it into 1st, 2nd, and 3rd. Now it flat WILL NOT go into reverse or first.

I'm thinking I need to put the fitting on the clutch fork lever back where it was (or move it into the rod a little more?) and see where it takes me. It seems to me that at both ends of the clutch rod the fittings are as far out as they can go. As I understand it, if the clutch is slipping in this condition its time for new clutch discs. Is that right?

I'd rather it just be a clutch than a bad transmission, but I'm still looking at the 4 speed for the future.
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Old 07-17-2005, 12:57 PM   #2
TN70C10
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Yeah, you need a new clutch. Really the adjustment is for setting the freeplay and pedal height. Its not for making a worn out clutch work again. Sometimes you can adjust one and get some grip out of it, but usually its just time to break out the big wrenches and get to work.
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Old 07-17-2005, 02:44 PM   #3
Lobo'74
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OK.

Next question(s):

- Once the transmission is disconnected if the levers on the side allow it to go into R/1st and 2/3 then the tranny is good and the clutch was the problem, right?

-Can I upgrade the clutch discs and keep the old pressure plate (assuming it is good)?

-How do I know if the old pressure plate is still good?

-What is a good replacement clutch to use with a high output 350? Not looking for a racing clutch, but i want one that will hold up better than stock. I want it to be smooth, and with less effort (I'm taking off the auxillary 2nd clutch return spring the PO had on it.)

-As long as I'm in there, replace the throwout bearing and the pilot bearing, correct?

-Any words of wisdom on this?
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Old 07-17-2005, 03:43 PM   #4
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I did the clutch in my 3sp/250 last summer. They say do all three-new clutch plate, new throwout bearing & new pressure plate. I'd be inclined to agree- all new stuff & you wont be back there again anytime soon. I had my flywheel reground too. I upgraded to a 12" clutch while I was there. I got a kit-clutch plate/throughout & pressureplate. my clutchplate was doing the exact same thing-but it also did it on hills too. Yes, do the throwout & pilot too-its soo ez while you are there. I didnt NEED a 12"er but it was a $15 upgrade from an 11"er & one day I'll put more power infront of it. It was an OEM clutch that they use behind diesels I'm told so it should take a tonne of power. TIP: pit the tranny into neutral before pulling it apart, & get new bushings for where the rods attach to the levers on the trans-this made all the difference for me. I think Mr. Gasket has good aluminum ones. & put a new boot on the clutchlever where it goes through the bellhousing-they are always rotten!
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Old 07-17-2005, 05:24 PM   #5
Lobo'74
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Well, I moved the fitting on the clutch rod that mates to the clutch fork back to where it was before. Now I can get 1st again, still no reverse. I took it out on the road. Had a little "clunk" going into first when I first started. It went away immediately and did not repeat going into 1st again.

Had a little vibration in the shifter initially (feel it, couldn't see it). It went away within a mile or so. Now it shifts smoothly into 1,2, or 3. Still no reverse. In fact, it seems to move into 1st even when I'm still rolling forward more smoothly than it ever has before.

Since reverse and first are on the same shaft I am guessing that my transmission is not bad and that it is a worn clutch that disengages enough to allow all the syncromesh gears to work fine, but doesn't disengage enough to allow the non-syncro reverse to engage.

Anyone have any thoughts about this?
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