Home-built articulated tractor build.

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Although not a true Kubota our little articulated tractor is based off a 520 Kubota my Father had. Dad had a sales sheet which had all the specs. on it, bucket height, turning angles, wheel base ect. Using those specs for a guide this is what we came up with.

The back is a little longer then I would like but as a mechanic I like to have room to work and could not stand the thought of pushing the motor up tight into the cab. As it is we have good clearance to work on the front of the engine.

Another comprise was the cab, would have preferred to have the front of the cab slope back at 10 to 12 degrees and the back be straight. As it was we had to push the front of the cab as far forward as possible. On the back of the cab the back wall comes up straight for 18 inches or so then angles back at about 14 degrees. Going up straight allowed us for room to work on the engine, tapering it back allowed some room while in the seat so our head isn't banging into the back window. Not the look I wanted but as they say, "form follows function,always."

This has been a long build, about 15 years. Sat for some time until my grandson showed interest and got me fired back up. Now to see where the weak links are. One is I suspect the front pivot which uses a front spindle of a C50 Chevy truck is going to be weak. Also curious to see how our 60 chain holds up. Little automatic trans-axle, a TH 125 GM, 90 Lumina, is light but as it is close to the motor hoping it will hold up.

Glass should be going in this weekend, storm on its way. Time will tell.

https://www.youtube.com/watch?v=_BLJ6wLCiDo
 

BigG

Well-known member

Equipment
l2501, FEL, BB, Rotary cutter, rake,spreader, roller, etc. New Holland TL80 A
Sep 14, 2018
1,950
774
113
West Central,FL
That grandson has a great grandpa! Very nice and I sure you both learned a lot and made some great memories. Well done.
 

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Must have been a lot of fun to build! Congratulations!
Obsession would be more like it Yooper. Ton of time in it. Would have been far more efficient to have bought a used unit needed some work. Once you get the idea in your head though it's hard to give it up. Some highs and lows along the way, its the highs keep you going. (-:
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
12,901
4,268
113
40 miles south of Kansas City
Roy, nice work. Patience, imagination, time and a pile of steel will keep anyone busy. It was Thomas Edison who said, "To invent, you need a good imagination and a pile of steel." You got good results!
 

coachgeo

Well-known member

Equipment
L225 w/woods Few Mowers & Back Blade, D722 in Motorcycle (Triumph Tiger), LMTV
Nov 16, 2012
2,460
32
48
Southern OH
awesome job to tractor and to family
 

BobbyK

Active member

Equipment
1995 B2400
May 20, 2018
101
42
28
Petrolia, Ontario
Gotta love builds like this!

Alot of guys think about building their own tractor...but you have actually done it.

And it articulates!

This just add's to the cool factor!

Way to go!
 

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Nice...now just work on your video skills;)
A good point Bobby. My video and computer skills are quite basic. Pretty much grab my Grandson 's camera and shoot. It looks petty good when he plays it back on the camera/phone but when he downloads to You Tube it sometimes flips 180 degrees and also will reformat so some of the picture is cut out.

He has a friend who is pretty sharp. I will question him on it.
 

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Although not a true Kubota our little articulated tractor is based off a 520 Kubota my Father had. Dad had a sales sheet which had all the specs. on it, bucket height, turning angles, wheel base ect. Using those specs for a guide this is what we came up with.


https://www.youtube.com/watch?v=_BLJ6wLCiDo

An update. Have had some snow and been able to give the tractor a pretty good workout or two. Gear train has worked well. Auto transmission temp has never really lifted off the peg. Engine temp has went up to 220 without the cooling fan kicking on. Believe these used to kick on at about 226 then keep the fan on until at about 206 but still makes me nervous. Believe I will put an indicator light on the dash which lights when the fan kicks on and then perhaps add a toggle switch which allow the operator to kick the fan on manually if so desired.

Certainly could use some additional weight up front, maybe three hundred lbs. When the blade is at an angle the front of the unit tends to walk off to one side.

Tires spin easily. There has to be a blow off valve somewhere. A u-joint, chain, weld on a drive shaft, automatic transmission. Something that breaks when under a heavy load. In our case it is tire spin which is a good cheap pressure release.

Both differentials, 14 bolt GM, are posi units. Interesting to note the posi does not seem to engage. The Gm posi has a unique clock spring style design rather than clutch packs. I suspect the slippage has to get to a certain speed to engage and with all our reduction we are not meeting that spec.

All the glass, six pieces, now installed, very quiet in the cab.

The 3.1 Gm v6 circa 1990 was prone to blowing head gaskets. Ours is not showing any signs of leakage but we currently have the heads off and are getting a light cut on them to true things up then will go back together with fresh gaskets and head bolts. Just figured we would nip this problem in the bud. Tech doing the work said he would not do anymore of these unless they were in pay loaders like ours. Everything at bench height and easily accessible. Far different job than doing it in a car.

Steering? Not sure we will ever get used to the steering which is simply a lever off the steering wheel hooked to a short tie rod end which in turn hooks to a simple hydraulic valve which operates a two way hyd. cylinder. Works pretty good in close quarters moving snow ect. but gets pretty twitchy on the road.
 

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Waiting for one small gasket and head gaskets will be done. Finished installing glass couple weeks ago. Yesterday went to settle up for the glass and rubber welting. Four windows rather large, two smaller quarter windows, also 60 feet of the rubber welting.

Total cost of 1030.00. This includes glass, cutting, rubber welting and sales tax. made our own patterns out of 1/4inch underlayment and did our own install. The rubber welting ran about 360 dollars. Satisfied with the overall cost, lower than I anticipated.

Used laminated glass. Might have mentioned before but the glass man said if had went with tempered glass would have been cheaper. On tempered they have to cut it first then send it off to have the temper put into it. I was surprised it would be cheaper, would think the extra handling ect. would run the cost higher.

With the cost of the welting and tempered being cheaper gluing in tempered glass is maybe something I should have looked into. Next time
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
12,901
4,268
113
40 miles south of Kansas City
Sounds like you have it whipped out. If you need more welting for a project, I have 6 different styles. I'd sell it for about 40 cents a foot.
 

roygage

New member

Equipment
M7040, M5040, DT 3000
Jun 15, 2015
30
0
0
estherville iowa
Earlier this week we had an inch or two of snow, another 3 or 4 last night. Both gave me an opportunity to play with the articulated.

I typically do about ten places the largest being our shop parking lot, 120 feet by 100. With the articulated already at work I used it to clean the big lot. Observations. The heater located under the engine cowl feeds exhaust into the cab. Did not expect this. There is a joint from the header pipe to the exhaust manifold which is leaking. Hopefully replacing this will resolve the issue. I would hook up a pipe to the intake on the heater and route it away but the heater hoses run right in front of it so that will not work.

Suction line fitting threads onto the hydraulic pump has a captivate O-ring. Darn thing leaks. Replaced a couple weeks ago, looked it over good for cuts or imperfections on the casting or fitting. Little worried perhaps there is a crack in the fitting or pump body. One of those deals just should not be leaking. Runs oil right down onto my main wire loom which due to the computerized engine control is quite thick. Not cool.

Steering. Current steering set up is a 2.5 by ten inch stroke cylinder which is operated by a simply fleet store two way hyd. valve. This valve is hooked to the steering wheel by an arm comes off the steering shaft and runs to the valve via a simple tie rod.

It works better than you would think and was cheap, did let us get it going and do our testing. That being said I will never be happy with it, gets pretty twitchy in particular when on the road. This will be the subject of another post.

Aside from these issues everything works quite well. The three speed GM transaxle has been flawless. We simply drop it into drive and run the four speed box in second. You really do not notice the shifts as it is geared down so low.Backing up is slow as reverse is only one gear. I find myself turning around after a run and driving back to the other end of the lot rather than backing up as I do with the shuttle shift of our 7040. It does turn sharp so works quite well.

Temp gauge on the auto trans has never broke over 150. The 3.1 liter motor never labors or works, just coasts along. Today the snow was light and the concrete had no ice on it, traction was good. Am sure I could use some weight up front but under today's conditions worked well, could run the rig right up the pile on the end. Not clear up but got the frt. wheels couple feet up. Couple of times with a good pile of snow in front of the blade I ran the tach up to about 2500 RPM, has good snort.

Have to back blade some of the stalls in the lot. Does not have enough down pressure on the blade to do a good job of that .

I did note some hydraulic whine after running for awhile. Possible that pesky suction line leak letting air in. Only thing currently running off the main pump is the power steering

The 60 chain on the drive from the back of the four speed to the back rear end is holding up good. You do not notice any drive line snatch from forward to reverse. Very happy about that.

Gas lid on the five gallon racing fuel cell we used is a pain in the arse to get on and off.

The biggest problem is I comparing it to a 2010 7040 with a shuttle shift. Back when I first started on this project I had no tractor at all. Since I have bought a L3000DT with loader and our 7040. Prior to getting the 7040 I would have thought the articulated was the cats meow, how quickly we get spoiled.

Will keep you updated.

https://www.youtube.com/watch?v=goCEWUEDRBM
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,298
4,853
113
Sandpoint, ID
It's quite a feat to make your own tractor from parts, but I would say your finding out what tractors cost so much.
It takes a lot of quality, well connected, well matched parts, to make a complete unit run completely as it should! ;)