5.6 gpm gear drive. What is your opinion of these gear drive units?

[POWERMEN INC 14]

I have 3 belt drive units, that put out 5.6 gpm.

What are the pros and cons of a gear drive?

I haven't bought gear drives, since I started this business in 1989.

At that time, without much knowledge, I killed myself daily, washing big tile roofs, etc, with a 5hp 1500 psi 3gpm gear drive.

Within a year, I went to a 9hp 4gpm gear drive and within the next year, I started with the 13hp 5.6 gpm 3000-3500 psi units, I use now.

I really don't remember much about the gear drive units I had, but I now know I was way under powered for some jobs and more importantly, way lacking in gpm!

If they make gear drives, that will work and last as long as belt drives, they would be more compact and not be breaking any belts! :)

I went from working with a minivan in 1989 to a open trailer with 2 machines and chemical pumps and tank in 1991, to the same equipment in an enclosed trailer in 1992 and have since reverted to a small open, solid steel trailer, with 1 machine mounted permanantly on that and a double chemical pump arrangement [sureFlo] and a 65 gal tank and I have another pw'er mounted in my Nissan Frontier truck.

If i'm not doing any chemical work that day, I just use the truck.

That's my story and i'm stickin' to it! :)

[Mathew Johnson 123]

I built one 2 years ago, Bought a 20 HP Kohler, gearbox with 2021 pump, K-7 Unloader, 40 gallon float tank. I have ran this hundreds of hours and have only changed the oil and one repair because of a poor setup that was corrected.....

Word of Caution.... Mount the unloader to an unloader block, not the pump

[POWERMEN INC 14]

I have never tried gear drive and i'm interested in what pumps you suggest. I have 13 hp hondas and now use 5.6 TS2021 pumps on them. I would like to get as much gpm as possible and I know my 13 hp's are pushing it to run 5.6 pumps. I have done this for many years though, with very few breakdowns.

Still, I want to hear about gear drive comparisons. :)

[Russ Johnson 141]

A 13 hp will run a TS2021 at its full rated flow, but at reduced pressure due to horsepower restraints. IMO the scale of machines goes as follows from lowest to highest:

Direct drive axial cam

Direct drive piston

Gear drive piston

Belt drive piston

With the gear drive, the pump does turn slower but you still get some heat transfer.

[R. Williamson 14]

Gear boxes are fine up to 20 hp but above that it your asking for trouble!

[John Orr 206]

I bought a new Comet gear drive to replace a direct drive pump on my back-up 13hp portable. Ditto on the lower psi, rated gpm. Other than the extra weight, the only downside is something else needing an oil change.

[Paul Kassander 26]

I have a customer that has about 20 of the gear drive units on 18-24 hp hondas with ts2021 pumps and he has had excellent results with them. The Higher end gear drives work well, just be sure it is rated for the higher hp motors. Thease ones we carrry that are rated to 27 hp.

http://mobicleaninc.com/store/category/bhf8/Gear_Drives_and_Pulleys.html

[R. Williamson 14]

It's the keyways I have seen fail at higher hp, not the gearbox.

[Chris S 14]

I've got a TS2021 and a Udor gear box hooked to a 15 hp Kohler. This set up runs great. The main drawback is the muffler on the Kohler is mounted over the gear/box pump, which does put some heat to the gearbox/pump.

[POWERMEN INC 14]

Thanks for all the input folks!!!

[Curb Appeal 14]

I have a gearbox and TS2021 to mate to my 13hp honda on the way now. Should be here Fri. We'll see. I'm extremely excited about going from 3.8gpm to 5.6gpm.

[Paul Kassander 26]

You will be very pleased with the difference, and you will save a lot of time.

[Curb Appeal 14]

All I can say is WOW!

I put everything together and had it up and running in no time. The difference is amazing. I cleaned 3 condo buildings in 8 hours this weekend and I flew through them.

The gearbox runs smooth as silk.

I put 75-90w mobil 1 synthetic gear oil in it. Is that correct?

[FCPWLLC 233]

Now with that money you made on those condos, you can buy a bigger engine to get the full potential out of that pump. I have a source for 15 hp Kohler's for $475. Let me know if you want to get one.

[Curb Appeal 14]

Now with that money you made on those condos, you can buy a bigger engine to get the full potential out of that pump. I have a source for 15 hp Kohler's for $475. Let me know if you want to get one.

I was thinking my next engine would be a 20hp. 15hp would get me 2900psi. 18hp would get me 3500psi. Hmmmmmmmm... I'll have to think about that one. That is a very good price.

[Curb Appeal 14]

Oh and something else:

I noticed today that my unloader stopped going into bypass a few times. I'd let go of the trigger and the engine load did not let up.

I've read that the unloader needs to be adjusted to compensate for the reduced HP but I'm not entirely sure as to what exactly needs to be done. When I got everything hooked up, I put the pressure guage on it and dialed the unloader out until the guage read about 2400psi with the gun trigger off.

Is this correct? Is there something that I'm not doing? Or did I possibly get a bad unloader?

It's kinda scary when you let go of the trigger and the engine doesn't ease up. I kept waiting for a fitting to blow...

[Chris S 14]

I know on k-7 unloaders, you need to replace something inside of it when you plumb it back to a tank.

[Paul Kassander 26]

Try squeezing the trigger and adjust the unloader untill your gauge no longer rises. Then back it off untill you see the needle just start to drop and you shouldn't have that problem anymore.

[simplesoulutions 14]

Three problems with gear drives maintenance on the gearbox inevitable leaks and depending on usage keyway failure on engine crankshft usually about 1 year of moderate to heavy usage. Reconsider Belt drive !

[Curb Appeal 14]

Try squeezing the trigger and adjust the unloader untill your gauge no longer rises. Then back it off untill you see the needle just start to drop and you shouldn't have that problem anymore.

Thanks for the tip!

I'm assuming that I should have the correct size nozzle in the gun. In my case, a #7.