Commando 800. 5085 trans problem

[nj1052 15]

I am based in the UK and have a 1-0120 Commando 800 with a transmission problem. I have used this machine regularly for the last 28 years for grass cutting and have noticed that there is now significant backlash in the driveline, particularly noticeable when the slope of the ground changes. I guess that I will have to split the trans but I am rather concerned about what I will find. Has anyone else had this issue?

 

Many thanks for your help.

[wheelhorseman 3,211]

Before you split the transmission look at your key ways / hubs on your axels- they could be worn badly 

Edited November 9, 2017 by wheelhorseman

[nj1052 15]

Well done! A spot on diagnosis! I have pulled both hubs and both keys are wrecked as are the slots in the shafts but the hubs look fine. Any suggestions for a fix would be very much appreciated!

[Achto 27,829]

A new set of keys and an addition of a second set screw 90 degrees from the original set screw (if your hubs don't already have a second set screw) will buy you some time. Eventually you will probably need to repair or replace the axles. I have removed the axles, welded the original key way shut, and cut a new full length key way in some of my axles. I realize not every one has this ability, but a machine shop should be able to do this for you if you take them your axles.

 

[Ed Kennell 38,811]

Here is a key way fix I did in 2015.

[nj1052 15]

Many thanks to you all for taking the time to give me your thoughts/solutions. I think I will pull the transmission, extract the shafts and take then to a friend who has more skill than me and also has a Bridgeport mill. The idea of welding up the damage and re-cutting new slots sounds like a good long term proper engineering solution which will see me out!

 

Once again thank you from the UK

[stevasaurus 22,884]

Here is a link to rebuilding a 5085 transmission...with videos, that should help you get her done. 

 

[nj1052 15]

Many thanks for the videos/photos which will make my life much easier once I manage to get the b*****d hitch pin out!

[Ed Kennell 38,811]

There are many threads and opinions on here regarding hitch pin removal.  My most successful  and easiest is to cut the pin off on both sides of the transmission with a 4.5" X1/16" grinder wheel.   Then put the hitch in a press to remove the two pieces of pin.  The piece in the transmission may have to be drilled out.

 

                           GOOD LUCK

[nj1052 15]

The problem is that the pin is stuck in the casing. I have cut the hitch off but the pin is well and truly "welded" in place. I have read most of the threads about removal and am about to try the candle wax approach. Drilling it out sounds like a long job!

[Ed Kennell 38,811]

I have had some success by drilling a 1/8" hole thru each half of the casing lug into the pin to inject penetrant.   Then tap the two holes for a zerk fitting for future lubrication.

[nj1052 15]

Got it out!!! Phew that was tough. I drilled into the casing lugs and injected some Wurth Rost Off and left it overnight. This morning I hit it with a drift, quite hard I may say, but it didn't move. Then I tried some heat and got a little movement. Then I tried the candle wax idea and a much bigger hammer, well actually a large wood axe, and more heat and it started to go when hit VERY HARD. The box is now apart and not in bad condition at all. I am going to take the shafts to my friend with the mill and see what we can achieve. It is very satisfying to be making progress, thanks mainly to the help offered here which is very much appreciated.

[nj1052 15]

I am aware how annoying it can be when help is requested and given but then no more is heard so here is my update on my transmission problems.

 

As suggested I went ahead with cutting new keyways in my driveshafts. After a bad job by a so called professional, not my friend incidentally as he was too busy, I bought a solid carbide cutter and did it myself on my worktop milling machine. This is a fairly light weight machine but if you go gently it is pretty good. In the meantime I had ordered the parts I needed for my gearbox from Lowell who was very helpful . Many thanks Lowell! Delivery took a while but it was quite fun tracking the package from the USA to home. 

 

Once the parts arrived it was just a case of assembling the new bearings, seals  and 3rd gear into the box and buttoning it up. My old wheel hubs were very bad from the woodruff key walling  so I used a pair from a gearbox I found from Ebay. The tractor is now back together and is fine. I am now carrying out a refurbishment of my 10 year old mower deck so I am ready for next season.

 

Once again many thanks for the help given by the members of this forum.

[Sarge 3,463]

Glad to hear you got it fixed - I know that feeling waiting for parts coming across the pond , bought a lot of stuff out of the UK over the years that we don't have available here in the US .

 

Sarge

[nj1052 15]

I'm back! After a further 6 years of successful mowing thanks to the help given here I now have another problem looming. My gearbox has gradually been getting noisier in second gear, the one I mainly use. In first its fine and in third its no so bad but second is bad. It makes a sot of groaning noise . I changed the oil, which was not too bad and not filled with metal, but that made no difference. Any suggestions on what the problem could be would be very welcome! 

 

Thanks again from the UK.