4wd fwd articulated tractor???

[cleatus]

I've been thinking I could use a Fiero engine/trans inthe rear of an articulated tractor with a cv joint centered at pivot point and chain drive to rear diffs. at each end to get lower gearing.
Anyone done this?

 

[Mith]

i have thought about this myself
my eventual idea was to have it belt drive (i guess this depends on how hard you are coint to use it, if you think chains will do belts may also)
you have a vertical shaft engine with a pulley on the bottom. with pulleys in the piviot of the tractor belt go to front and rear gearbox (the ones like they have on lawn tractors with the pulley at the top). one gerbox for front wheels and one for rear (havent planned how the gear change mechanism joins up yet). im witning to get another gearbox the same to do this.
i dont know what scale you plan to do this on (HP?)
i think overall you idea would work, but the losses on the joint in the middle when turning would be great. hydraulics would in my opinion be best to have for a larger machine (like a power trac)

 

[cleatus]

The Fiero I have , that was given to me for removing, has a v6 . For the drive joint in the middle I've concidered also what Toyota used in place of u joint at front spindle.

 

[Mith]

V6??!! i dont think belts will work for that, maybe chains might not be the best idea either
have you seen junkyard wars (think thats the US equivalent of scrapheap challenge here) when the use chain drive it always fails, cant think of one time when it didnt break
you might be better off getting an old 4x4 with low geared diffs (could also get diff locks on here)

 

[Ozarker]

How about using the engine to run a hydraulic pump and then have a hydraulic motor driving each wheel?

 

[notamustang]

One of the large tractors used wheel mounted hydraulic motors to drive each wheel. You could drive the wheels in any direction and have independant steering per wheel with as much ground clearence as you wanted. I would use drive shafts if you go solid axle. You can get upwards of 40 degrees off set on a c v shaft.

 

[Kaliburz]

I've seen one.....well, a mini articulated garden tractor. Weather it was 4wd or fwd, don't know. Someone made a model of an early 8020 JD.....

But, this site might give you some ideas:

It's not exactly pretty, but ....... might provid some inspiration.

 

[cleatus]

The idea was to use parts that would cost less. That's why I was thinking mabe two front diffs with linkage with small rams for control. Out put shafts could be mated with timming chains to each diff and would provide reduction.

 

[pat32rf]

Cleatus- Our idea was to use the engine/tranny from a small fwd car, mount it with the two drive axles running front and back, then connecting them to a 4wd front axle at each end. That way you have a solid frame but can steer each axle for a sharper turn. You would gain about 3.5 or 4.11 (depending on your axle choice) in your diffs so a small engine should still give enough torque at the wheels as long as you didn't go too big on the tires. Would your Fierro engine/trans fit this configuration?

 

[Brad_Blazer]

Why not run the half shafts directly into the axle differentials? The Fiero front end should have a pair of CV joints on each axle so you should be able to get quite a bit of flexibility.

You'll need some stout axles since you will have 4x torque coming out of the transaxle differential compared to a bare transmission.

You could make it even more interesting by putting a pivot point at each end of the transaxle.

I've thought about an articulated vehicle with a powered "twist" pivot to allow it to walk out of sticky situations. If you are going to build something yourself there is no point in duplicating what can be bought. /forums/images/graemlins/wink.gif

Brad