SPF Shifting Trouble, TKO 600.

jhv48 · #1 (**permalink**) 12-21-2009, 03:42 PM

OK, you guys have talked me through every problem I've faced so far.

I have done all the searches I could but still have a few questions regarding the TKO 600.

For the first 1500 miles, all was well, slipped smoothly into all gears but ground into reverse unless I slipped it into 4th first. So far, sounds normal.

Now, it has gotten harder and harder (requires more and more pressure to get it into first at a stop) and it grinds in reverse now after slipping it into any other gear first.

Shifting into any gear on the run is effortless and no grinding. Even into first while moving is like butter. 2-3 shift has never been a problem. Goes right in.

So, why the sudden grinding in reverse after putting the box in another gear first? And why does it take a good hard push to engage first at a light (no grinding, just a nice firm slow push)?

I have a hyadraulic clutch with no way to adjust the slave cylinder. No rod with any adjusting nuts. Fluid reservoir is full and no leaks apparent.

So, what could be causing the change in gear engagement of first and reverse?

SOLUTION

Everything from the clutch to the master cylinder was as good as new. the problem was the pilot bushing was defective. Binding just enough to cause the input shaft to keep turning even with the clutch fully disengaged. Replaced it, all is good now.

STL Mark · #2 (**permalink**) 12-21-2009, 04:14 PM

Sounds like mine too.

The way I solved it was to go to 2nd gear then into 1st - smooth. Then for reverse - same thing get into first (above method) then into reverse. I'm no expert, but there is a reason for it (read about it here) and it works for me.

Silverback51 · #3 (**permalink**) 12-21-2009, 05:00 PM

Sure sounds to me that the clutch is draging.

You sure there is no adjustment between the slave cylinder and the fork?

cdnus · #4 (**permalink**) 12-21-2009, 05:08 PM

Jack it up on stands, put it in 1st. gear & have someone try to spin the rear wheels while you fully depress the clutch. It goes without saying the engine is NOT running at this point.
If there is any drag at all the clutch needs attention.
If there is no drag you have a more serious problem.

Craig

jhv48 · #5 (**permalink**) 12-21-2009, 05:36 PM

There is no adjustmnt nut on the slave rod. And the clutch disengages just fine.

Are these boxes that tempramental?

PANAVIA · #6 (**permalink**) 12-22-2009, 11:24 PM

The other test -- car on jack stands or a lift. wheels clear of floor and anything else.

Trans in "N" (netrual)

Clutch pedal to floor.
Start Car
Keep Clutch pedal down on floor
move lever towards first (slowly)
have someone observe for wheel movement
wheels should not rotate *AT ALL* all the way into 1st gear.
Keep Clutch pedal down on floor
move lever back to neutral, then to 4th, up into N, then R.
again wheels SHOULD NOT MOVE AT ALL.

if they do -- the clutch is not disengaging all the way.

If they dont move, and you still have difficulty, the shifter (esp aftermarket) or shift forks are damaged.

Steve

Archrms · #7 (**permalink**) 12-23-2009, 06:25 AM

If it was a clutch issue, wouldn't it happen in all gears all the time? Sounds more like a synchro issue to me.

ekrupa2 · #8 (**permalink**) 12-23-2009, 01:58 PM

Jim - my slave also has no adjustment rod/nut. I have always meant to replace it but until then I have adjusted my slave with shims. Works great so far.

jhv48 · #9 (**permalink**) 12-23-2009, 04:19 PM

Thanks all.

The clutch is fully disengaging, but I might just try that shim suggestion just to be sure.

Blas · #10 (**permalink**) 12-23-2009, 08:26 PM

NAPA autoparts has a adjustable rod. Quite inexpensive too. Have the part number somewhere, but I just stopped in and picked one up...

ratsnst1 · #11 (**permalink**) 12-23-2009, 08:45 PM

So basically, your clutch is not engaging all the way, you need more throw in the pedal, I dont know how to do it on a spf car.

ken swart · #12 (**permalink**) 12-23-2009, 09:10 PM

I might be stating the obvious, but you can adjust the clutch pedal on an SPF

jhv48 · #13 (**permalink**) 12-27-2009, 11:45 AM

There is an adjustment on this car. It's behind the clutch pedal in the driver's footwell.

There is a rod with an adjustment nut on it. I adjusted it so that there was a hair of freeplay and that seemed to help. However, there are three holes on the clutch pedal where this actuation rod attaches to the pedal. Mine is set in the middle hole. Would moving it to the lower hole (thus increasing the stroke of the rod help any? Kind of nervous running a clutch with no freeplay.

Blittleton · #14 (**permalink**) 12-27-2009, 02:56 PM

I agree with most about the clutch is dragging. Your slave cylinder isn't pushing your clutch fork far enough. I build a nice slave cylinder set up that will work with most if not all tko-600 setups.

859-630-9099 or bill@gcperf.com

jhv48 · #15 (**permalink**) 01-09-2010, 09:21 PM

The only way to adjust my clutch is to remove one or two of the four shims that are holding the slave cylinder mounting bracket to the trans.

Will let you know if this is the answer after a drive tomorrow.

patrickt · #16 (**permalink**) 01-10-2010, 07:42 AM

Quote:

Originally Posted by jhv48

The only way to adjust my clutch is to remove one or two of the four shims that are holding the slave cylinder mounting bracket to the trans.

We just had a recent thread on this last week. The cure is to drill a hole in the end of the fork and use a threaded rod from the slave. It makes adjusting your clutch a cinch. Unfortunately, drilling the clutch fork while it's still in the car is virtually impossible. There might be some sort of special drill that would do it, but I don't know of one.

WardL · #17 (**permalink**) 01-10-2010, 07:51 AM

How often does this happen? It seems crazy to have a clutch that occationally needs adjustment, but there is no way to adjust it? How was it installed and adjusted at the build?

patrickt · #18 (**permalink**) 01-10-2010, 07:57 AM

Here is the thread I referenced. Lots of nice pics in it.

http://www.clubcobra.com/forums/show...postid=1015719

jhv48 · #19 (**permalink**) 01-10-2010, 08:00 AM

Quote:

Originally Posted by WardL

How often does this happen? It seems crazy to have a clutch that occationally needs adjustment, but there is no way to adjust it? How was it installed and adjusted at the build?

The slave has a solid arm with a bulge on the end that nestles into the depression on the fork. The only way to adjust this kind of slave is to remove or add shims (mine had 4 originally) to the slave mounting bracket that function to move the slave cylinder either closer to or farther away from the fork. A very time consuming way to adjust the clutch I might add.

jhv48 · #20 (**permalink**) 01-15-2010, 04:34 PM

So, my clutch is adjusted fine now (begins to catch about one inch off the floor).

And I figured out a way to shift into reverse with absolutely no grinding.

Start the engine with the trans in neutral AND THE CLUTCH FULLY DEPRESSED. Since the trans is not connected to the rotating engine, nothing in the trans is spinning. Shifting into reverse is a piece of cake. Just move the lever over and back. Should have thought of that earlier.