Cub 100 shifter fork repair

JPWright · #1 01-11-2018, 12:02 PM

I have to say you folks are a marvelous resource for my Cubs. I read all the narrow frame posts religiously.

I bought my 100 from a 14-year old. He had “modified” the carb linkage, clutch, and cut off all of the lift parts. I have resolved all of those issues.
I assumed that he hot-rodded it with wheelies, speed shifting, and the like. I am having some trouble with the transmission locking up between first and reverse, and third gear popping out when plowing snow. Third gear does not engage like it does on my 122. I looked over some parts diagrams and the service manual and my uneducated guess is that the “shifter forks” are cracked or bent.

I did a search of our site for shifter forks and came up with a lot of resource material. I have not been inside any transmissions but this repair seems that all that is necessary is to remove the shift lever plate and everything can be done from there.

My question is, can the forks be repaired (bent back with a hammer, adjusted)? The 100 is my snow tractor and I would like to have it fully operational for the next snow storm.

J-Mech · #2 01-11-2018, 01:20 PM

Before anyone does a bunch of guessing.... take the top off the trans and have a look. No way to know what is broken until you do. Can they be repaired.... maybe. You'll have to look at them first. No, the are only visible from the top cover. If they need removed, it is more involved.

Lanceskene · #3 01-11-2018, 01:51 PM

I would have a magnet handy while the top cover is off.... maybe some bits down there that dont belong.

I bent fork, I would heat it cherry red before trying to straighten it.

ironman · #4 01-11-2018, 03:25 PM

I once had a 122 that kept popping out of third gear. When I finally got around to pulling the shifter assembly out I found that the bolt that holds the fork to the slide rod was loose. After tightening with thread locker never another problem. Hopefully yours could be that simple.

JPWright · #5 01-11-2018, 05:52 PM

Thanks for the fast replies. I will have that magnet ready and hope I just have to tighten a bolt.

johncub7172 · #6 01-12-2018, 12:18 AM

From what I've come to know, the problem has been more frequent in the wide frame models, or that of those with the longer shifter that would allow for more leverage, making it easier to break. But, it does happen to some narrow frame once in a while.

finsruskw · #7 01-12-2018, 09:22 AM

My 1200 does that in 2nd and I noticed the other day it did it in 3rd a couple times while pushing snow.
I have had the top off but could not find anything apparently wrong.
On plow days I just use a tarp strap to hold it in 2nd. PITA!
Hope you can find a fix.

JPWright · #8 01-13-2018, 08:43 PM

I split the tractor today following the directions in the Service Manual and cleaned up the transmission before pulling off the gear shift lever.

The shifter forks were indeed bent and one of them was loose. After covering the opening, I used a vice grip to very gently bend the forks back into shape and put the loctite on the bolts. I got most of it put back together before sundown, EXCEPT hooking up the driveshaft. That is always a difficult task for me and took until 7 pm.

I did a test drive and went through all the gears. It works fine now.

Thanks for keeping me motivated.

jaynjeep · #9 01-13-2018, 09:30 PM

Awesome!! Glad it worked out for you and was a simple fix!

Every now and then we all get lucky!

Thanks for sharing!!

jbrewer · #10 01-14-2018, 08:33 AM

Quote:

Originally Posted by JPWright

I did a test drive and went through all the gears. It works fine now.

Thanks for keeping me motivated.

Good work!

I've straightened those before and they continue to give years of service.
I think there's some folks that are of the "if it don't fit, force it" school of thought and THAT is how they get bent.

Mine have never failed since I straightened them out, and I doubt they ever will since I don't gorilla them.