Calling on the Getrag Guru (James)

[Paychk]

James



I'm close to closing up my Getrag, but the shims on the counter shaft aren't even close. I need some new ones, as there is evidence that the shims have spun. Also there is signs that the bearing cones for the cluster gear have spun in the case, the bores are ok as the cones fit snugly.



The counter shaft shim math works out to a required 0. 061" - 0. 063", does this sound in range to your experience? I have, as near I can tell, 0. 026" for shims and they have ridges and thin spots from spinning.



The main shaft works out to 0. 042" - 0. 044" and the shims I have are 0. 040" I think this is a little on the slim side, as I put all new tapered bearings in.



Also I need to replace the 1-2 shift fork, the original thickness was 0. 260" and has worn to 0. 140" have you ever done this? If so what is the easiest method to replace the fork?

 

[1stgen4evr]

Probably ought to PM this but there may be others that want to know. And I don't have any secrets.



"Bearings may have spun": Well be sure you are not just on a ridge that make you think the case is ok. I have a case if you think it isn't ok. You probably lost some distance with wear on the big snap ring where the front cup contacts which would account for some extra clearance. And you would normally just make that up with shims unless the snapring is too thin. The shims (as I expect you know) are to make up for machining differences in the course of manufacture. More or less is fine if you get the preload right.



As far as the total shim thickness, I never checked. I just set to whatever is required and let it go at that. Put the thickest shim against the bearing. One caution. If you had a problem with the pocket bearing that DIDN'T require a new mainshaft, be certain that the shoulder of the bearing stub isn't erroded so that the make up distance is too close on the 3 - 4 shift.



I have described in detail what I use as methodology when setting preload. But I go by feel and I add shims till I have the slightest perceptable resistance as I turn the shaft. I don't put it up slack, period. And that is hard to define as to what I feel with my hand as I am checking. As you can see, the pocket bearing is on the small side and if you get too much preload, you quickly kill the little booger. And you are back to square one.



Yes I have changed a fork. One or more will often be bad for one reason or another. Take a look at the underside of the cap and you will see that the forks are fixed to the shift rails with pins. You will have to take the center set out and then you can get to the left or right. Note the small knock out that allows the OD reverse fork roll pin to go out through the cap. The roll pin on the 1 - 2 fork is sometimes too long to bump all the way out. You may have to grind away some of the roll pin to remove it. You can get to it after you have the center rail out. A little flat blade on a dremel will do the job. That will require a new pin. The center rail has space to allow the roll pins to go out through the stick tower. You may have to shift the rail toward the back a tad for one of the roll pins.



I am going to PM with a couple of other things that may be of considerable importance and my email address so we can continue as needed with other questions.



James

 

[Paychk]

James



I made sure that the case bores for the bearing races weren't damaged, I'm not sure of the words to use, but the look of the metal I could tell there was movement of the races. There is no difference that a dial caliper would show or a finger nail could feel in the case bores. I was concerned with wear to the snap ring, there was just a polished spot were the cup made contact with it again a visual sign of movement but not enough to measure.



The pocket bearing and where it mounts on the main shaft had no damage, but it has a new pocket to ride in as the input and cluster gears needed placement due to missing teeth.



I made a mistake on which shifter fork, it is the 3-4 gear fork, i. e. the one mounted on the center rail. Sounds easy to replace.



Thanks for your time, appreciate it