Transmission repair YM180D; split tractor at Transmission to Clutch housing

BC Dave · Friday at 12:59 AM

Couple of questions and update; I found and received a new after-market 1st / reverse shift fork for a JD 650 / 750; that I believe should work in a YM 180D, same tractor different label; actually the 650 transmission / fork. Hopefully it'll fit!.

Have been spending quite a bit of time taking the YM 180D apart to the point of trying to splitting the transmission from the clutch housing; all seemed a bit of a struggle as its sitting on a trailer with 1 ft sides, snowed and freezing temps, but under outside covered but open sided carport.

Funny thing is all bolts are out; shifters out and its seems quite stuck together; done lots of wiggling on ROP and pulling by hand so far not budging! ... please advise how to get it pulled it apart!. Both halves are Magiver supported; but arn't budging; is there something in the tranny holding it together?~!; lol! Words of wisdom please ... now thinking further tonight, I need to chain the bucket to the front of the trailer and use a winch cable under the trailer and attach to secure hitch point ...

Also I have a JD 650 / 750 manual; showing the 650 as the exact tranny as the 180D; (but 180d has 3 cyl diesel engine) ( ho im learning lots ....

Also beyond separating; I note several ball bearing spring dents; 3 for shifters and 2 more for hi low range shifter and another one ( cant remember for what ... looks like I need to remove shift forks for range shift and the 4-8 shift forl / rail, before I can remove the gear transmission set (and bearing "quill").

Tractor stuck in 1st in Cariboo ..

Cheers BC Dave

AaronM · Friday at 10:53 AM

I suspect it is probably just stuck on a stud, dowel, splined coupler, or possibly a bearing. I pulled one apart (different model) recently that I SWORE still had a hidden bolt somewhere and it was just a rusted dowel. Those are not super easy to get apart in the best conditions let alone on a trailer with a loader attached in the snow. You have to pull it apart perfectly straight or it will bind up. The YM180 service manual goes into great detail describing the process

(See attached picture).

Aaron

BC Dave · Friday at 1:26 PM

... have a JD650 / 750 mechanics manual, fairly detailed but sometimes details are sketchy / missing ...

....another detail ... If equipped with MFWD (Mechanical Front Wheel Drive), the step bracket for MFWD lever must be removed. This will let the lever move forward while separating transmission, so that lever pin will disengage from shift collar.

bmaverick · Friday at 9:05 PM

BC Dave said:
... have a JD650 / 750 mechanics manual, fairly detailed but sometimes details are sketchy / missing ...

....another detail ... If equipped with MFWD (Mechanical Front Wheel Drive), the step bracket for MFWD lever must be removed. This will let the lever move forward while separating transmission, so that lever pin will disengage from shift collar.

Did you drain all of the hydraulic fluid yet? And did you pull off the jumper hose to the hydraulic suction pipe?

There is this incredible video made by @AaronM

ponytug · Saturday at 12:43 AM

Great video. Thanks @AaronM!

All the best, Peter

BC Dave · Saturday at 12:38 PM

This was time consuming; 95% back together as of 7:30 pm last night. Cl / Tranny connection was stuck together with liquid gasket seal and maybe some rust on longer studs, lots of wiggling and adjusting lift plate jack on front end. Struggled to get to back together again too, atleast the trailer was flat / level and it was a little warmer yesterday ...

in this repair, discovered that you can partially pull the gear train out in-tacked on the bearing quill plate, found that I could leaving the hi-low range shift in place and attached; after removing 4-8 shift fork you can partially slide gears out intact just enough to remove broken 1st and reverse shift fork, punch out roll pin, slide shift rail out to plate, but leave in at the last point to hold dent balls & springs in place; gently remove broken shift fork top; gently place new fork on rail after checking roll pin hole that turns out to be slightly larger than the OEM so have to spread roll pin with a stout knife blade hammered in split ... find right spot on 1st / rev gear for shift fork position, then starts sliding it all back together again ... then start checking that it all shifts properly ... have not started for test ride yet.

BMavric, Yes good video of clutch replacement front of clutch to engine connection....
But I'm working on the other end at the transmission to rear of clutch housing, with 2x gear drives, main and 4x4. and interior transmission gear train to differential connections.

winston1 · Saturday at 4:15 PM

Sounds to me like you know what you are doing. Pictures would sure be nice.

BC Dave · 2025-11-02T00:22:51-0400

winston1 said:
Sounds to me like you know what you are doing. Pictures would sure be nice.

Been taking pics, ill try posting later, but may noy have documented every move; I wanted to get it back together while it was all fresh; slow carefully following mec service guides and parts diagrams, referred to pics a number of times to make sure exp hoses were routed back the same place; fork / gear placement was a little tricky. Tested today all works and no hyd leaks too; YAHOO! Cheers BC D