Sheared the Lower Lift Arm Cross-Shaft (MT180D)

coldsteelva · Jun 13, 2016

Murphy's Law hit me hard this weekend. I was pulling my 60" Woods RFM downhill through tall grass and managed to straddle a 8 inch tall x 3 inch diameter twin stump with my MT180D; my mower however slammed full on into it, bringing the entire consist to an abrupt halt.

Of all of the components of a 3 point linkage (or mower) that are easy to replace, what broke was the 30 year old, right hand end of the cross-shaft pivot (the inboard connection point for the lower lift arm). Any ideas on how much force is required to shear a 7/8 diameter solid steel rod?

I will upload pictures later (taking pictures of my fubar was not my priority), but do you think that the sheared end could be welded back on and be as strong? Anyone know of a source for that MFR. specific cross-shaft?

coldsteelva · Jun 13, 2016

Billrog · Jun 13, 2016

Weld it up nothing to loose. Just don't run into any more stumps.

CalG · Jun 13, 2016

Shear at a transition can not be calculated.

It broke. ;-)

Kernopelli · Jun 14, 2016

Can probably be repaired by a local welding or machine shop or I feel pretty comfortable in saying that the lower link attachment can be replaced with one for a Case IH 235. Mitsubishi made their compact tractors of that era and a number of them have pretty good cross reference between Mitsubishi and CIH. You can look at a parts diagram Case (235) - CASE IH TRACTOR (1/86-12/88) Parts Diagrams ( Chassis/Attachments Part NO. 1273263C1) . You can always go the salvage route too http://www.tractorhouse.com/listing...d-machines/list/?Mdltxt=MT180&Manu=MITSUBISHI or http://www.tractorhouse.com/listing...antled-machines/list/?manu=case+ih&mdltxt=235

PILOON · Jun 14, 2016

I have the same tractor and have sheared mine for the second time.
In my case snow blowing and hitting some protruding rocks is the cause.
Catching the 60" blower corner on buried boulders puts terrible stresses on that shaft.

I took the shaft to my local machine shop and they made me an exact copy and I recall it cost me $60-70.
They used cold rolled steel and it actually stood up rather well.

Assuming your break is about 3" from the end at the shoulder I'd advise welding will not work, just too much stresses at that point.

Any good machine shop should be able to make you a copy with no trouble.

To remove that shaft you need to pull one wheel, otherwise it is not a big job.

I would not even think of looking for used as anything you might find probably has has as many stress as yours had just B4 yours broke.
Besides judging from my hunting for MT parts the used market prices are ridiculous.

PILOON · Jun 14, 2016

I have the same tractor and have sheared mine for the second time.
In my case snow blowing and hitting some protruding rocks is the cause.
Catching the 60" blower corner on buried boulders puts terrible stresses on that shaft.

I took the shaft to my local machine shop and they made me an exact copy and I recall it cost me $60-70.
They used cold rolled steel and it actually stood up rather well.

Assuming your break is about 3" from the end at the shoulder I'd advise welding will not work, just too much stresses at that point.

Any good machine shop should be able to make you a copy with no trouble.

To remove that shaft you need to pull one wheel, otherwise it is not a big job.

*****I PM'd you*****

coldsteelva · Jul 17, 2016

Well, I was able to have a local welder repair my flub for only $25. He stated that the joint would be softer since the original part was hardened (tempered?) steel so try not to hit anything else. I put the tractor back together and have mowed about 6 hours since without issue. I'll admit I have been a bit more timid than in the past.

Here's some pics of his work: