By tony on Unrecorded Date: Edit

max hydro conversion
Hello all; i am a 98 max4 owner who is sick of his sticking clutches and kinda crappy t20 performace; having to adjust frequently and deal with a screaming engine all the time. I am looking into swapping my t20 for a couple of hydro motors and mounting them in the same area driving the chains. I was looking for others who would be interesting in sharing in a disccusion of the project and findings. currently i have researched a couple of motor options but have not found any with the performance that i am really happy with. this is why the t20 is around because its hard to find a hydro motor that will put out the tourque and speed that the t20 can. I think that the steering will drasticly improve because not the aatv will be able to have one drive going one way and the other drive opposite so in theory it will be a nice turning machine. The engine may even be able to reduced and weight saved. do you need 20hp to drive these hydro motors.
well i will conitinue to search and hope others will post
thanks

By liflod (Liflod) on Unrecorded Date: Edit

I'm wondering why you have a screaming engine all the time. The torque converters should take care of that so the engine speed should not be that high.
Also, the hydro machines usually have the engine running at a constant speed and the vehicle speeed is controlled by valves. The biggest complaint I've heard about hydro machines is the screaming engine and the noise complaints I've heard about the Max IV's were to be able to sneak to thier hunting spot.
One of the main advantages of using hydraullic motors is to quit using chains.
So I think its the wrong idea to switch to hydraulic if you want a quiter machine with less maintenance if you are still using all the drive chains.
How often do you have to adjust the transmission and what do you mean by sticking clutches?
Maybe something is not set up correctly on your machine causing all the grief ?

By csrichmond ( - 206.66.249.2) on Unrecorded Date: Edit

Although I'm new to 6x6's (bought a well used one after shopping for a few years), I am familiar with mechanical power systems and agree with Lifold.
A hydraulic system for moving vehicles has more losses than a straight mechanical "direct drive".
Example - look at Compact Tractors where hydraulic systems typically have lower PTO HP and lower pulling power for the same engine size.
A hydraulic system is usually designed for constant RPM from the power source (engine) and speed is varied by fluid flow control.
Example - watch someone work with a backhoe.
Hydros certainly can require less daily maintainance but have higher initial costs and repair costs.
Straight mechanical systems are more maintance intesive (if you want them to last) but are typically less costly and easier for us "nuts and bolts guys" to understand and repair.

Each drive system has benefits and shortcomings so you choose that which makes you happy.

By tony larose on Unrecorded Date: Edit

hey guys thanks for the post.
the machine in question is a max 4 with a noisy 20+ hp kohler command; albeit the muffler is not very good at muffling the thing i expected a pump would run at half to 3/4 throttle rather than the belt system which i can push to full throttle alot to get it to "shift" quickly. You guys may be correct about my max a little out of "tune" but its a bitch to do.. i still havent put my rear seat back in since the last adjustment. I notice one of the plungers comming out of the top a litle on one side when i steer but not sure that its not suppose to - it brakes both axles ok.
anyway back to the hydro swap. It looks like for about 500 bones i can get the pump and controls needed to make the thing work. I am having some questions on what size motors to look at seeing the motors in question dont really tell you how fast they will rotate at a given flow but rather make you calclulte it. this is something that might be a expesive lesson learned. One thing that will be nice if this all works out is to get true 360 turns by turning one set of axles the opposite direction. i agree with losing the chain drive mech. but that seems to be the simplest part of my machine. if i could rid it of that tranny and not so smooth shifting trans i would be happy; i wouldnt have to sit in the middle anymore and could prob. find a 12hp engine to pump the fluid. I have been thinking of finding some old zero turn mowers and checking out the drive mechs on these; after peeping under one at the local homedepot i have seen these use rather larger top belt driven motors and not small units like i was thinking. so i will have to keep my eyen on the right configuration of things for this possible swap. if this dosent go farther than this board i will have learned alot and at least answered the question.

By liflod (Liflod) on Unrecorded Date: Edit

Be careful when comparing a 6 Wheel ATV to a zero turn lawnmower. The zero turn mowers have very little traction. The wheels almost always spin before the engine dies or before the motors break. In a 6x6, the traction would break those little motors before the motors would break the tires loose. Even though the zero turn mowers have some pretty large engines on them, the power goes to the blades.

I think you can go through your machine pretty well,new muffler included, for $500 and still retain some resale value. Those one-off home builts would not sell to quickly if you wanted to get rid of it.