gardentractorproject
Garden Tractor Project
Blog Type Description of Building A Homemade Garden Tractor
This will be the second home-made garden tractor that I will have built. The first was 35 years ago, built from parts of a 1954 Ford. It is still running today, but was sold many years ago when I moved from Utah to California.
This new build is based on a rear axle, transmission, and steering gear from a 1974 Ford Courier (Mazda) 2-wheel drive light duty truck.
The plan is to make this web page entry look somewhat like a web log or blog. I will be adding pictures and text at various times during construction. This way viewers can follow along with what I am doing, and the finished write-up will be a chronological description of how the tractor was built.
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25 March 2008
I have already cut 11.25 inches from each side of the axle housing. This will bring the outside width to around 40 inches.
An engine has been purchased for the tractor. From a few minimal test runs, it seems easy to start and quite responsive to the throttle. Actual installation in the finished tractor will tell the story regarding whether it is powerful enough for the job. My earlier homebuilt garden tractor used an 8 HP Kohler engine, so this 6.5 HP unit is not all that much smaller.
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3-April-2008
The transmission has a switch installed that was used to activate back-up lights on the original vehicle. Present plans are to utilize this switch to apply power to a 556 timer chip and power amplifier for driving a back-up warning beeper.
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18-April-2008
A pair of 11.25 inch long cut off axle housing sections are lying in front of the transmission (lower right of this photograph). Lines for cutting were marked by holding a paper strip around the axle housing with the ends parallel to insure the lines were at right angles to the axle.
First Thoughts of how this might all fit together. Steering layout may be changed to drag-link arrangement. Vertical frame structure on rear will support 3-point hitch, and mounting points for seat back and roll-bar assembly.
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25 June 2008
After considering making my own tractor seat, looking for a suitable seat on Craigslist and Ebay, and checking prices at various tractor parts stores...I opted to purchase a Boat Seat from Walmart.
A large pulley will be fixed to this end of the transmission shaft. This will provide approximately 8:1 speed reduction and will be the clutch mechanism.
At $24.95, this seemed like the best choice for a comfortable seat with easy mounting method. This seat is covered with durable plastic with a back which folds down to lower its profile and to protect the seat when the tractor is not being used.
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15 April 2009
This is the cut-down differential housing.
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This is the wheel end of the cut down rear axle housing. The cut was made 2 inches inside the backing plate mount in order to keep welding away from the wheel bearing race.
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This is the 4-speed manual shift transmission. I would have preferred a unit with the shift lever located further forward than this, but "it was FREE" so guess I can't complain. If necessary, the shift mechanism can be extended forward with a linkage of some sort.
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Bob WB6FOO suggested that now the tractor should be named:
"Little Red Riding No-Hood".
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24 April 2010 Updates
It has been some time since I updated this page, but work on the tractor has continued. You will see a bunch of pictures below that show upgrades (and some repairs & design re-think efforts).
This transmission has the pilot shaft bearing mount in the bell housing instead of in the transmission front casing. This will complicate things a bit because I cannot just remove the bell housing and throw it away. It is needed to hold the bearing and oil seal. Not sure yet how this will work out. I will probably just trim the bell housing to same size as the transmission case, throw away the clutch throw-out bearing and actuator, and fasten my belt clutch pulley directly to the pilot shaft.
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28 March 2008
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The inner axle shaft has been cut and slightly bevelled in preparation for welding. I removed 11.25 inches of shaft from left and right axles. This matches the amount that was cut out from each side of the axle housing.
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The two axle sections together, prior to alignment and welding.
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A section of angle-iron has been clamped to both axle sections to hold them in proper alignment for welding.
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27 April 2010
Adding hydraulic brakes for rear wheels. The original Ford Courier rear axle and hubs had hydraulic brakes, but I did not connect them during the initial tractor build. Individual parking-brake manual levers were considered adequate at the time. Now, with more free time it seems opportune to add hydraulic brakes as well. The new master cylinder comes from a junked-out Mecerdes-300 (How's that for class!).
Here is a little closer picture showing how angle-iron stock is being used as an alignment jig for welding axle sections together.
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2-April-2008
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Axle Stub, Welded and Ground Down. Grinding the welds down is required so the axle shaft can be removed for future maintenance without having to pull the outer axle bearing.
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Brake pedal is not yet installed, but it will mount on that hinge and have a swiveling push-rod to activate the brake master cylinder.
I never claimed to be a professional welder, but the axle is straight and should be strong enough considering the small engine size and light weight of the finished tractor.
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3-April-2008
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Master Cylinder linkage to brake pedal
The axle stubs have been welded back together and slipped back inside the axle housing. Axle splines engage the differential to the same depth as before part of the axle and housing was cut out. Overall width outside left tire sidewall to outside right tire sidewall is now 40 inches.
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Brake Pedal. Still needs a coat of red paint, but mechanically it is finished and works as expected.
Square bosses on wheel backing plates will be trued up to horizontal with a level and the differential adjusted exactly horizontal with a level on the flat surface of the differential drive coupling plate. Once this is done the axle housing sections can be welded together.
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4-April-2008
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The narrowed rear axle has been welded back together.
Rear view of the narrowed rear axle. Overall width including tires is now 40 inches. 11.25 inches was removed from each side.
Here you can see the welds where the axle housings were put back together.
And a close-up of the welded axle housing.
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Painted Rear Axle housing. Not my choice of color, but what I had available on the shelf.
Steel for the frame has arrived (see it lying under the axle housing) so work can now continue with frame manufacture.
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18-April-2008
Here is a very rough mockup with boards and nothing bolted in place. This shows roughly how all the pieces will be arranged. Of course the steering column will be much shorter and wood will be replaced with metal structure.
Front view of the very rough mockup. This shows approximate placement of the single front wheel, and engine size relative to the rest of the vehicle.
That bell housing has got to go. I'm holding the idler sprocket in it's approximate position. A 9 inch matching sprocket will be attached to the transmission pilot shaft. This provides 3:1 speed reduction. A 9 inch pulley will be attached to the idler sprocket and driven by a 2.5 inch pulley on the motor shaft. This provides 3.6:1 reduction, for a total reduction of 10.8:1. At 3000 engine RPM this should give me around 7 MPH maximum speed in high gear. In lowest gear the minimum speed should be around 0.4 MPH.
A belt tension pulley on an idler arm will make up the clutch assembly. Plans are for the clutch to tighten the belt when released and for it to force a small brake pad against the idler pulley and sprocket assembly for braking when the clutch is depressed. This eliminates any tendency for the vehicle to creep when the clutch belt is slackened.
The U-Joint shown here was made up from half the front U-Joint and half the rear U-Joint. This then mates up with both transmission and differential. I felt that the U-Joint was necessary because I could not be assured of getting perfect alignment if the transmission tail-shaft were to be directly connected to the differential input shaft. This way there is some allowance for flexing of the frame and for possible misalignment between transmission and differential shafts.
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23 April 2008
When I removed the bell housing from the transmission I found that this exposed the pilot shaft bearing, and jack-shaft bearing. It also removed the oil seal from the front of the transmission. To keep the bearings in place and to maintain the oil seal, the back wall of the bell housing had to be retained. Since I didn't want the whole bell housing sticking out front of the transmission, the back wall of the bell housing was cut off and re-attached to the transmission.
Here you see the cut down bell housing with the back wall bolted onto the transmission. Cutting went rather quickly (less than 15 minutes) using just a hand grinder and narrow kerf abrasive type metal cutting blade.
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26 April 2008
Axle Hanger Brackets. One is bolted to a frame member with 2 half-inch bolts (the nuts are welded in place because they will be hidden once the axle hanger brackets are welded to the rear axle.
Frame member and axle hanger bracket (not yet welded to axle) showing placement.
Rear view of the frame that I welded together today. It is 20 inches wide and 4 feet 3 inches long. That overhang at the rear will attach to vertical structure for hitch (towbar) and seat support, as well as a socket for the roll-bar.
Front of the frame showing transmission location and an approximation of front wheel placement. Note the splined hub from the original clutch plate mechanism has been welded into the 9 inch chain sprocket and that sprocket installed on the transmission input shaft.
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18 MAY 2008
Axle hanger brackets are now welded to the axle. In order to have the frame at my desired height I had to cut the ends off the previously welded up frame and weld on a section to go over the axle. This actually works quite well because now I have a place to add the seat mounts that has 1/2 inch clearance over the differential housing.
A closer look at the axle hanger bracket welded to the axle, and showing my sloppy weld on the frame member. Guess I need to grind that ugly weld down a bit to hide the evidence.
Here is the frame attached to the rear axle & differential via welded on hanger brackets and a pair of 1/2 inch steel bolts on each side holding the frame to the hanger brackets. The drawbar will mount 3 inches below axle center on those downward pointing rear tube-steel pieces. Placing the drawbar below axle center helps to avoid the tractor turning over backwards when pulling heavy loads.
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19 May 2008
The transmission is now bolted in place with one cross-member underneath it and a second cross-member bolted to the front plate mounting bolts. I have temporarily positioned the drive pulley so you can see where the belt type clutch will be located.
Another picture of the transmission mounting, showing cross-members welded and bolted to the frame. Some thought went into this arrangement because it is necessary to allow for future maintenance by unbolting cross-members, then lowering and sliding the transmission forward to remove it from the differential.
Here is a front view of the transmission mounting arrangement. The temporarily placed shaft, idler pulley, and drive chain shows planned location of a belt type clutch assembly. In this picture you can also see the two hand-brake lines leading forward from the rear wheels. These will each have a hand operated brake lever to allow individual rear wheel braking for making very tight turns on slick surfaces (i.e. snow and ice). The regular hydraulic braking system will be operated with a single foot pedal for braking both rear wheels simultaneously.
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20 May 2008
Steering Gearbox Modification:
Without modification the steering gearbox would not fit where I needed it between the frame side rails. The next few pictures show how I shortened the gearbox housing and sector shaft.
The gearbox disassembled and 3 inches cut from the gearbox housing. Next comes curtting the same amount from the sector shaft.
If you have ever wondered what is inside the steering gearbox...this is it. A tapered sector gear is held against the recirculating-ball driving gear by downward pressure on the sector shaft. Excessive play is taken out by the tapered sector gears being forced against the drive gear by that bolt which screws down through the gearbox cover.
Here is a closer shot of the part I cut out of the gearbox housing, and yet-to-be cut sector shaft. The trick here is to cut exactly the same amount from the shaft as was cut from the housing. I will cut it 1/16 inch too long and then grind the ends down until everything fits.
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22 May 2008
The sector shaft has been cut and the ends bevelled to allow deeper weld penetration.
A little better image of the ready-to-weld sector shaft being clamped in a piece of angle stock to hold it aligned for welding. Once welding is complete it will be ground down to slightly less than the original diameter so it can be re-inserted in the steering gearbox casting sections and used to hold them in alignment for welding of the gearbox housing.
Top of the cut-down and welded steering gearbox housing.
This gearbox was welded with a MIG type welder to avoid cracking as the welds cooled. After cooling, the sector shaft rotates smoothly and fits in the same position it did prior to being reduced in length.
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11 June 2008
Still quite a ways to go, but this is a significant milestone. It can now be rolled about on it's own three wheels.
Same thing...opposite side view.
Still have to make and weld in a pair of small brackets to offset the front wheel cross-brace a couple of inches forward so it will clear a potential larger 11 HP engine installation. At this point I'm still planning on the 6.5 HP engine, but am leaving room for the larger one if necessary (i.e. If Harbor Freight lowers their price a bit more).
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17 June 2008
Still playing with how everything will fit together. Here the front wheel support has been made and welded in place. Now I can roll it around the shop on it's own wheels.
A closer view of the front wheel assembly. That pair of vise-grip pliers is the temporary steering mechanism.
Left side view showing potential placement of engine and steering gearbox.
Same as above, but right-side view.
Below you can see the chain drive and belt-clutch bracket. The belt-clutch arm pivots on the transmission front protrusion (a 1.25 inch pipe fit tightly over this nipple, so a grease fitting was added and support arms for the larger pulley & smaller sprocket shaft were welded to this center-point swivel mechanism. This lets the belt-clutch move up & down while keeping the same tension on the chain & sprocket part of the drive mechanism.
OK, all the temporary stuff set off and out of the way. This is getting ready to add the engine support rack, and eventually a support bar for the steering gearbox.
Same as above but right-side view.
Adding parts of the engine support rack.
Engine support rack side rails in place.
Another view with the engine support rack side rails welded in place. I raised the engine mounting position to allow for possibly replacing the 6.5 HP engine with an 11 or 13 HP electric-start unit at some future time. A larger engine would not clear the front wheel support if the engine were mounted at frame level. Raising the engine mounting rack by 6 inches allows for almost any size engine to be installed.
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19 June 2008
You cannot tell it from the photo but the engine is running and spinning the transmission. The only spare belt that I had available was too long to allow the engine to be mounted lower. The engine mounting bars will eventually be moved to bolt under the side rails instead of on top of them. A new belt (the correct length) will be purchased, and it will look much better (I hope!).
A closer look at the belt type clutch assembly, still with the engine running.
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25 June 2008
Yesterday I completed most of the rear hitch assembly and started on mounting the newly purchased boat seat..
Those vertical bars are drilled and have welded-in bushings at the bottom where the lower bars of a 3-point hitch will be attached. A horizontal brace and hitch lifting shaft will be welded across behind the seat.
Space between bottom of the seat rack (not yet built in this photo) and the rear axle is reserved for hitch lift actuator (electric screw jack or hydraulic cylinder...not yet decided which it will be).
Here the new seat is sitting on a piece of plywood, with it's position approximating how it will be mounted on the presently-under-construction seat support rails and slide assembly.
This picture sort of shows the size and position of the seat relative to the rest of the tractor. Seat support rails are now in place, but the slide mechanism has not yet been built. The vertical support bars are now capped with plastic inserts, but eventually there will be a hinged roll-bar attached there.
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26 June 2008
Seat slide rails and the adjustment mechanism are now in place.
A closer view of the seat position adjuster. A 10 inch section of 3/8 inch threaded rod is used to move the seat back or forward. Seat adjustment did not require this precise adjustment method, but the design and fabrication was easy, and I wanted to try this as preparation for doing something similar in another project later this year.
The seat bolts to the slide rail cross-members using four 1/4 inch diameter bolts.
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29 June, 2008
The steering gearbox is mounted using a flat metal fin bolted to the top of the transmission and the bottom of the steering gearbox. NOTE: This later proved to be unworkable and was removed. Final steering gearbox placement is in additional superstructure which is not shown in this picture.
Right side view showing the mounting fin.
Here the top bracket for the steering gearbox has been fabricated and bolted in place. It is still too long, but the part extending toward the shift lever will be cut off later when a lower support bracket has been welded in place.
A larger left-side view of the steering gearbox support bracket, and some experimental positioning of possible upper steering shaft support brackets.
Right-side view of the steering gearbox support bracket, again with some experimental positioning of upper steering shaft support structure.
A socket wrench universal joint was used as the flexible link in the steering shaft. After cutting the longer shaft I filed it square to fit the U-joint.
This lets me play with setting the length and angle of the steering wheel shaft.
Approximate position of the steering wheel. Not sure at this point if position will be adjustable, or fixed.
First driver's-eye-view with a steering wheel in place. This is encouraging. This project might someday actually become a working tractor.
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1 July 2008
We have a steering wheel!
The Steering Wheel Pedestal Mount is done. A 4 inch long section of 1/2 inch iron pipe was reamed to fit the steering wheel rod, then welded into a section of 1.5 inch X 1.5 inch square tube. This tube then became the steering wheel support pedestal.
Those boards clamped to the underside are a temporary deck so I could sit on the tractor and make adjustments to final placement and height of the steering wheel.
This picture shows a close-up of the steering wheel mount pedestal and the socket-wrench type universal joint (flex-joint) that allows the steering wheel to be tilted rather than flat.
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16 August 2008
It has been a while since I posted new tractor progress pictures here. The delay was because I had to re-design the steering arrangement...several times. Now I have a layout that works very well, and it even turns right instead of left when I turn the steering wheel to the right (I'm very embarrassed about the first design, which turned backwards!).
This shows the tractor in an almost finished condition. Everything works. Forward speed is between 0.2 MPH (idling in 1st gear) and 18 MPH (full throttle in 4th gear). That top speed is a bit too fast so I may eventually change the clutch pulley to a 10 or 12 inch diameter instead of the present 7 inch unit.
Left side view as of 16 August 2008. It is not pretty, but it is a functional tractor.
This shows several things. The clutch mechanism has both foot pedal and a hand-clutch lever. The hand clutch allows me to add pressure to the drive belt when pulling very heavy loads. Eventually changing from the present 3/8 inch wide B-belt to a 1/2 inch wide A-belt, which will match the pulleys, should eliminate any need for additional belt traction. The steering drag-link is visible below the steering gear box and sticking forward of it's actuating arm.
This is a close-up of the clutch actuated braking system. It is a wooden block that presses on the clutch pulley and on the drive belt when the clutch is fully depressed. This stops the transmission from spinning and facilitates shifting gears. If the transmission is in gear, it also acts as a brake for the tractor, with enough friction to slide the wheels.
The original steering gear box was cut down (again) to make it small enough to fit in a position which allows a longer actuating arm for the drag-link to the front wheel assembly. This effectively "gears-up" the steering action to make the front wheel turn 80 degrees in each direction when the gear box turns 42 degrees in each direction. A section of pipe serves as the steering wheel shaft support and has a brass pipe fitting (bored to fit the shaft) as the steering wheel support bearing.
A section of thin steel tube was cut, spread, and tack-welded in place for keeping feet and clothing out of the universal joint. Those tack-welds will eventually be replaced with some 1 inch iron angle stock and bolts. I tack-welded it because I was out of short 1/4 inch diameter bolts and it was too late in the evening to go to the store for more.
Front view. As noted earlier, it is not pretty, but it is functional. Next project is to add the front mounted blade and lift mechanism.
This picture shows that it can turn quite sharply (about 75 degrees) and will turn around in almost it's own length. I still have to connect up the individual rear wheel brake levers (the original hand brake mechanisms) to have even tighter turning capability. The hydraulic master cylinder will be added at the same time to provide hydraulic braking on both rear wheels. This will make a total of three braking systems (1) the clutch friction brake, (2) the individual rear wheel brakes, and (3) the hydraulic braking system on both rear wheels.
A front oblique view, still showing the sharp turning capability.
And lastly, a left-side view. I am happy with the design. The tractor has plenty of power (will easily spin it's tires on pavement if tied to a truck bumper and the truck's brakes are set)., the right speed range, and did not cost me very much to build it. The real test will be ploughing snow this winter (if global warming doesn't melt all the snow!). Next addition will be the roll-bar with lighting on top and a belt driven generator to power the lights.
I will post more at some later time, but for now the basic tractor project is finished. It will soon get front and rear earth & snow moving blades, then a rear mountable earth ripper & sprinkler pipe trench digger. Plans are already being formulated for a small trailer to pull behind the tractor. I'm not sure yet about building a mower attachment, but if I do this it will probably be a towed or pushed mower deck with it's own engine.
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10 September 2008
Since last update I have purchased a riding lawn mower ($50 at a yard sale) so won't be adding a mower deck to this home-made tractor. However, still need it to have a snow blade, and possibly a rotary snow thrower, but that is another project in itself.
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16 September 2008
Still adding a few things to the homebuilt tractor. The hand clutch lever has been removed. It was not necessary after I improved the foot clutch linkage and increased spring tension on the clutch belt & pulley arrangement.
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The 3-point hitch arrangement is now complete, except for manual lift arm...or possibly a hydraulic cylinder, for the up-down action.
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The 'stinger' adjustment was made from a 1 inch acme-threaded rod that Walmart sells for mounting weight lifter weights.
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And below you can see how it all looks with the 3-point hitch built and installed.
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Still some more additions to go on this tractor, but work has slowed to the point where approximately monthly updates will be made to this web page. That way you will see some actual accomplishment with each update.
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Here you see the tractor with snow blade on the rear, sitting in the breeze-way between my house and workshop. The tractor is 40 inches wide and the gate in front of it is 41 inches wide. Now you know why I picked that particular width for my cut-down rear axle assembly.
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This picture shows the rear mounted blade and it's manual lift mechanism.
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5-January-2009
Recent snowfall (6 inches in one night) required a bit more traction so I added a pair of tire chains. This makes the tractor almost un-stoppable, even in deep packed snow.
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In this picture you can see a close up of the tire chains and also some detail of the manual lift mechanism for the rear mounted blade.
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