I Need Help Designing a Hydraulic System for a rototiller

[CARNUT510]

Just as mentioned in the subject I want to build a system for my rototiller. I have a Large rear tine tiller with a 8hp gas engine. It currently uses belts to drive the system. You may be asking why? Because I have a itch... Im bored... Okay so I relize I am going to need a pump, a drive motor, Oil tank, filter, and a control valve. I just dont have any idea where to start...where do I buy this stuff? Whats the math/formulas on figuring out what kind of pump I need. I have a little general info... The Engine is 8hp, I dont know the specific RPM it puts out yet. But their is a 3" pulley on the engine, and then about a 7" pulley on the main shaft going into the transmission. Again Im green, but eager to learn about hydraulics...Any info would be great... Thanks! Joao...Oakland, CA

 

[kcj]

I will speak for many people watching from the sidelines. although we all started somewhere, and love to work on interesting projects on the side, the amount of time invested in such projects is huge. Hence, no one wants to reply!

I would suggest plenty of internet time, get some Parker or Vickers books, take a bssic hydraulics course or CD training. Learn the types of pumps motors, open and closed centers, hydrostatic, etc. Then apply what you know to the application you have. You need to understand the principles, not just plug in formulas.

Most industrial vendors won't help you, they honestly can't spend hugea mounts of time to sell $500 worth of stuff, then be blamed when the system isn't right.

Most consumer store salesreps don't know beans about what they are selling. They can figure a pump or motor size, but have no clue about the load control valves, cooling, filtration, etc.

So, the responsibilyt is on the user to learn a lot.
There are many good books out there, I just don't personally have a title to recommend at the moment.

k

 

[CARNUT510]

Thanks for the info, I actually Picked up a couple used books on amazon.com yesterday. I Will keep ya updated...Thanks again...Joao Escorcio...Oakland CA

 

[Icanfix]

Lets start with the gas engine. Most of the utility motors that go on lawn mowers, snow blowers, roto tillers etc, are governed at 3600 RPM. So you have a starting point.

Since this is a (I just wana play) venture do you have any idea how much you would want to spend? A starting place for pumps and motors is northerntool.com. There are more of them out there that a search will reveal.

Eaton makes a nice little variable hydrostatic transmission in a couple of sizes. The one on my garden tractor is an M11 and rated for 20 hp. Sells for about $700. Input 3600 RPM for maximum output of 2000 RPM.

http://hydraulics.eaton.com/products/trans_light_duty.htm

Your application doesn't require a variable speed hydraulic drive. So you can just go with a constant volume pump and motor. The basic displacement ratios would be 3 pump to 7 motor.

Have fun!

 

[kcj]

burdens surplus center is also a good source. actual surplus and better quality stuff usually then northern.

they have some basic formulas in the catalog, and also sell the womak books, although not cheap.

parker books have been the basic reference for 30 years, I am not sure what is still out there, but there were several topics.

http://www.surpluscenter.com

I am happy to help with specific questions as the time comes, just can't take the time to start you from scratch.



kcj