Full hydraulic machine

[Trackster]

How fast would you or anyone say you could go with a full hyd setup?

My trackster goes ~15 mph now with a Honda 24hp motor. It has never run out of torque on any incline. With the original motor it would run over 20 mph but the machine just really wasn't made for that (read terrifying because any change in input made you think you were going to wad it up). I believe the 2 stroke that it came with would run 5k rpm and the honda is only 3600, both are direct coupled so I gave up the top speed in exchange for no smell, reliability and a huge noise reduction.

[rcn11thacr]

I still think if you wanted to “roll your own” and make a TRACKED amphib from scratch, the best route is to use the example the military has. Pick your choice of motor, place it wherever you choose in the vehicle. Use either a front or rear area for mounting a transmission, go thru the tub and use a single gear on each side to drive each track. Considering the track would be HDPE type material (since that’s what most of us would have access to) I’d say the gear that turns the track should be made out of the same type material. I think the gear should be as thick as possible. In the case of my Adair Argo tracks I would make sure the tooth of the gear fills most of the area available in the track. Using similar material should eliminate most of the wear and tear from friction if a dissimilar material were used. I can only speculate on what the life expectancy would be on the tracks, that part would only be known after testing had been done. However i would assume the chains in the Adair type tracks would reduce tearing up the track due to tension, etc... (design a track tensioner to take up excess slop). As for driving the tranny? Use whatever you chose, driveshaft, chains, or a hydro setup depending on what type of tranny you choose. Does anyone feel this type of set up would be inferior? Comment on the pros and cons of this please…

[john swenson]

rcn 11, i think your right. i have sure seen alot of homebuilt tracked vehicles on u tube made by russian guy's. they do alot of what your talking about. motor, trans, rear axles and homemade tracks and cogs. check it out. some are really cool ! johnboy

[akcrawler]

Al,

Thank you for your post. I had not heard of the Hagen transmission, but went and looked at a couple of internet posts on it. You are right; it is truly a marvel and would certainly simplify operation of AATVs that come equiped with it. I wonder if there was a reliability problem with it? It seems strange that this unit didn't catch on if it was reliable.

I wonder if one can still get them?

Mike

[Nubs]

[rcn11thacr]

Interesting tidbit that may help out with this thread even though its not directly talking about hydros:
Notes on Tracked Vehilcle Steering

[rcn11thacr]

Another idea if someone were so inclined; Use my basic idea in first post i did "today" on this thread and include a pair of variable hydro pumps from a skid steer/track loader to power the external gears that turn the tracks. Granted this will only work in the case of a guy that wanted a precise, slow speed unit since my understanding is that 12.3 mph is the max for a loader. Granted that speed “may” (correct me if im wrong here) increase since the vehicle we are talking about is much lighter.

[Noel Woods]

I think you are correct about the weight/speed computation. A 4000 pound skid steer may top out at 10-12mph, but the same drivetrain in a 1000lb aatv should do much better than that.

I do think that when you factor in that an aatv can probably get away with one wheel motor per side, the speed should increase due to no parasitic load from the 2nd same side motor. This machine would have to be tracked to transmit the power and to have enough traction to be worthwhile.

[jerseybigfoot]

Befor you start spending any money, you should do the calculations. Guessing with hydraulics is a shore route to failure. Even calculating the torque to spin a hydrostatic tandem pump at start is required if its direct coupled. Too small an engine for the pump and starter has insufficient torque to turn the engine and pump fast enough to start. There are other thread on the forum directing you to the calculations. Or Google vehicle hydraulic drive calculations.

[kghills]

I wonder if they have a new design yet that gets rid of the chains? how often do you have to tighten them? do they have automatic tentioners? are they automatically lubed? Still have to carry extra chain when going out? whats the top speed like and how is the boyancy does it sink low in the water?

Mudd-Ox has had a full hydraulic machine for a couple years now. It is not sold in this country though. Every once in a while when I stop at the factory there will be one there ready to be shipped. They look very heavy duty and I was told they are expensive because the pumps and motors are pricey units to make it work correctly.

Keith.

[whipper-ag]

[kghills]

Why would you want to spend thousand's of dollars to build something that might only go 12 mph.
Why don't you just buy a front end loader and take it off-roading.
You could take it to Busco and rid the trails of debris while your trail riding,so everyone else can do 25 to40mph.
You'll be like a lonely maytag repair man riding all by yourself.

Whipper

And as you scream down the trail at 12mph with the engine turning 3800rpm with the pump howling and the motors whining and the cooler fan buzzing away while burning up about 12 gallons of fuel an hour, you can use that private time to wonder how long it will take you to walk back to camp.

Keith.

The Coot2 has 2 6 gallon tanks.

[rcn11thacr]

Keep in mind I said I'm throwing out ideas, I didn't say I was planning to make one of these with a hydro setup. Only other ideas for different forms of propulsion.

?Keith: what is the model of the machine that mudox sells over seas that your talking about? If it's so heavy duty, why isn't it offered here? Keep in mind when u respond that I'm asking an honest opinion, not trying to fling mud or say anything bad about mudox.

[kghills]

Keep in mind I said I'm throwing out ideas, I didn't say I was planning to make one of these with a hydro setup. Only other ideas for different forms of propulsion.

?Keith: what is the model of the machine that mudox sells over seas that your talking about? If it's so heavy duty, why isn't it offered here? Keep in mind when u respond that I'm asking an honest opinion, not trying to fling mud or say anything bad about mudox.

I don't know a whole lot about the full hydraulic Mudd-Ox other than Matt calls it the "Canadian Machine" and he will not let me take pictures of it, but its not a secret he says. It has some big engine and two speed or maybe even a three speed hydraulic pump and some fancy wheel motors. I think it is a track only machine and some of them have 7000 hrs on them with no maintenance issues. Special frames and I think they are heavier than an XL Mudd-Ox but still float. You could always ask about it in the Mudd-Ox manufacturers area of the forum if you want more reliable information.

I'll give you an honest opinion on any hydraulic machine all kidding aside. I really do not think they are for the recreational market. All these threads about them just talk about theory and how they could use a lawn mower or skid steer pumps and motors blah blah blah. First off, you can't just grab any cheap hydro system and figure it will work in an ATV. Just doesn't work that way. To have both power and speed you need big horsepower and multiple speeds and expensive motors. That's just the way it works. Even if and when you would get that part figured out the reality of driving it just sort of kills it. Think about it for just a second. Think about every hydro thing you have ever used. You start it up seems good right? Well you don't go anywhere at idle. The pump and motors are designed to run at 3600-3800rpm. Before you move you throttle up. Not like a conventional vehicle where you only apply throttle when you need it, you throttle up to the motor and pumps operating RPM and then proceed to move at your desired wheel/track speed to navigate over obstacles or down the trail. All while pumps motors and cooling fans are screaming away along with the engine fan and exhaust. You are basically running at WOT all the time. Trust me, your wife and family will not be impressed. My Coot2 is fully hydraulic. It is very capable and everybody that looks at it thinks it is the ultimate off road thing. I start it up and let it idle, they all go oh, that's cool. Then I throttle it up and its all over. Most tell me to shut it off. If you can get them to take a ride, 5-10 minutes is all they can really stand. Maybe that's the reason they made about 8000 Coots (CVT clutch with a transmission) and only 66 Coot2s (full hydraulic machines) That's my take. I don't mean to put anybody off, and discussing things is all fine and dandy, but I like to look at things and ask "then why aren't there more of them" or why didn't anybody buy it when it was used in this thing. If you can't provide an answer to the question it usually means it didn't work as good as people thought it would or as in the case of a full hydraulic machine, in my opinion, is suited for a commercial application but not a recreational.


I even installed a variable throttle (originally it had two engine speeds, idle or 3600rpm) using a linear actuator from a Mudd-Ox so I can vary the engine speed but to use Hi gear or run any obsticles in Lo gear you really need to run at full throttle just like any skid steer, utility tractor or zero turn mower I have ever operated.

Keith.

[Buzz]

A re-designed and properly engineered machine like the mudd-ox works well in all situations- recreational and also hard-working (commercial/backcountry towing/hauling) conditions. It also doesn't need to be operating at full-throttle or even close to it to do most anything you need it to do. In fact, most of my use (even navigating tundra and climbing hills) seemed to be 1800-2200 rpm. BTW a kubota uses very little fuel at that rpm and not much more at higher rpms. Let the hydraulics do the work. Amphibious machines aren't designed to go fast anyway, but with some of the pumps/motors currently available you can get that too. Engine choice is very important to making the whole package perform like you think it should.