Pto Rpm

Which gear would give the PTO a speed of 540? I’m assuming it would be first gear.

 

Well, that's going to depend on the engine speed and the transmission gear ratio...

 

I read The gears in the rear housing are also interchangeable so your ground speed can vary a little to the PTO.

 

I figured there would be a bunch of variables involved. I have a shaft tachometer I use for my engines, so I’ll check it with that.

 

Just curious, why the 540 rpm needed, what u powering?

 

Whatever I want. That’s the optimum speed for running any pto driven implement.

I would like to put a finish mower on eventually.

 

If my memory serves me correctly, the rear pto gearbox has 2 gears of different tooth count which can be installed in either position to give a slight underdrive or overdrive (relative to the input shaft rpm) depending on application.

 

Found ground speed/rpm/gear/range charts over on the CJ2A Page. These charts are based on the 20 and 24 tooth gears in either setup position.

Unusual Rear PTO Gearbox

 

Have a link on FarmJeep.com to this site Willys PTOs Lots of good info.

 

Not to hyjack, but anyone know of a rear mount garden tiller?

 

I've used that page several times when trying to determine what model of pto I have. Very useful! I would love to get a governor for my cj5.

I would start by searching craigslist.......

 

Here’s the jeep at an idle. The pto spins around 175 rpm. Guessing the gears are setup for the under drive which is perfect.



And here it is revved up. I had to switch scales. It’s turning at 750 rpm at half throttle at the engine.

 

Found it on eBay.

 

I did some math and determined that the values listed on the chart I posted a link to above are for a T90A transmission with gear ratios of 2.79, 1.55 and 1.0, 1st, 2nd and 3rd, respectively. A T90C has lower 1st and 2nd gear ratios so pto shaft speed will be lower, as well as ground speed, for what it's worth.