A1 tranny help 020

M

moliver

New member
Howdy
Problem: Gingerman, first session fine, even with the off-roading!!
Second session going great until I try to shift from 4th to 3rd, before turn 11, clutch feels weird and cannot make the down shift or get it into any gear, I coast off the track. I finally get it into 1st gear and go to the start line, where dumby me takes it out of gear. I pop the hood for Doug to take a peek, because i think the clutch cable has snapped. Its attached and feels properly adjusted. I push the car back to my spot.

What has been checked:

Clutch properly adjusted.
Shift linkage properly adjusted.
Trans fluid at proper level.
Clutch seems to work....put car in 5th gear and let off the clutch and the engine stalls.

What is weird and really pisses me off:
Got home and car shifted fine bringing it into the garage and off the tow dolly. Checked it over again tonight and found nothing wrong, ran around the block a few times NASCAR style and no problems.

Any ideas?

I don't really want to yank and disassemble the tranny, but I really cannot afford to go to the track and find out the car isn't going to run for me.

Thanks for any ideas!!!
 
1) Check that all bellhousing bolts are tight (and maybe also that all dowels are in place).

2) Check for a bent clutch pushrod.

3) If tranny is a worn-out pre-'84 2H, it could also be an internal slop/binding problem. I've never seen this problem with a newer '84-up (4k, 9A) box, though.
 
moliver,
I tend to be brutal on clutches and have had every problem in the book. 98 percent of the problems have stemmed from the clutch itself. installing a puck resolved many of the problems, but the pucks we use (Kennedy Engineering) don't have the springs in the center, so the flat steel spring on the pressure plate likes to pop away from the big rivet. Sorry to tell you, but I bet your going in. Good Luck
 
What kindof fluid? Only happen when hot? If so the fluid might be incompatable with the syncros and you get nothing but slip and no grip, hence you will never sync the gear.

Broken pressure plate will feel the same, but should happen when cold as well. You will also usually hear grinding when going to Reverse becasue the input shaft is still spinning.
 
Fluid is Redline MTL.

Seems to only happen when hot.

I have around 9 hours of track time on the trans without incident till last weekend, always running the MTL.

Shifts fine in reverse when cold.

Thanks for the comments guys....hopefully its just the clutch.

Mike
 
We had this happen with Mobil 1 synthetic 4 years ago. We have only used redline MT90 since. No experience with any other fluids. We have had a broken pressure plate rivit that causes this. Check and make sure all the straps on the PP are tight.

Your clutch will have to be dragging to cause what you explain, save the external parts that others have suggested.

If it happens again, try reverse once it happens with the engine running and if you hear a grind, the clutch is not open. (no syncro there) (previous suggestions are valid - pushrod etc).
 
I'm w/ the others, and think that it may be a PP issue. Could you shift the car with it turned off and not rolling?

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608
 
Yep car shifted fine when it was shut off and not rolling.

Hi ho hi ho its off to remove the clutch I go!!

Mike
 
To check the Reverse you really need to have the engine running. That is the only way you will spin the input shaft. Once the dog gears are lined up with the engine off it should shift fine if all your linkage stuff is ok. You can get bound if the dog's hit right on but the synco doesn't have anything to do since the output and input shafts are at the same speed (0 rpm).

That is why if the clutch doesn't open or the sync's are not grabbing (fluid/worn out) you have to accel or decel the inertia of the engine with they synco (unless you assist with the gas pedal) to get the input shaft speed to the speed of the output shaft. It just doesn't like to do that.
 
Well it was the clutch. The friction material on one side was partially cracked off. It was an OEM Sachs clutch.

Any suggestions for something more track worthy?

Thanks guys.

Mike
 
And Stu at BSI suggests MTL. Those guys build enough 020 boxes, I'm inclined to go w/ their suggestion.

------------------
MARRS #25 ITB Rabbit GTI (sold) | MARRS #25 HProd Rabbit
SCCA 279608
 
Whatever the fluid is that BSI (Stu) suggests is what we have been using for 4+ years with no issues. I said MT-90, but it might be the MTL then it says 90 weight somewhere. When you get it by the case, you kind of start forgetting what it says.

I hate to say it but I don't think the cracked material would be it IF it was gone. If it was flared out and causing the clutch to hang ON/ENGAGED, you will get the reverse grind and the hard engage. If it was totally missing, then the clutch would want to slip under load and also want to open easier. Your not shifting when hot sounds more like syncros, or a PP/Clutch that is not releasing. Make sure you look at everything good before you slap it all back in. The bent rod could also cause it like stated because you don't open the clutch all the way.

Also, we do run the 4 puck. Stu sells a kit with everything (Including the PP bolts I believe). Flywheel are extra but they are just so cheap why not replace them.
 
Originally posted by Bill Miller:
And Stu at BSI suggests MTL. Those guys build enough 020 boxes, I'm inclined to go w/ their suggestion.
Click to expand...
Bill, I went around and around with this with redline oil. I too have rebuild many a box and in California MT 90 is what works best.
 
We have always run a synthetic ATF. It has a very high sheer strength, and doesn't cost HP. Never had any problems or wear issues, its just a pain trying to keep the trans from leaking. Paper gaskets just don't stop the stuff.
 
MT-90 if one or more drivers on hard on gearboxes, MTL if all drivers are smooth. Extremely hot temps (So. Cal.?) might be another reason for MT-90, but it costs a tiny bit more in drag...
 
You must log in or register to reply here.
Back
Top