PT Stump Grinder

[MossRoad]

Rick,
Sorry to hear of your troubles. /forums/images/graemlins/frown.gif

I, too wondered about the lack of instructions. In this day and age you just expect it with everything.

 

[Rick_Taylor]

The stump grinder motor was ordered against the business since it actually owns the PT, other than that no problem ordering. We'll see.

There is a hex bolt in the end of the motor shaft, on the flat side of the grinder wheel and also a setscrew on the side of the shaft between motor and wheel. I haven't tried to remove them yet. If they're difficult I'll try a hand impact tool I've had since my motorcycle days. Hope I have the correct bit.

 

[duane]

Rick,

Just wondering what size is the hex bolt (or what size socket) that holds the grinder wheel on the motor shaft?

thanks
Duane

 

[Rick_Taylor]

I don't know bolt size yet as I haven't tried to remove it since I don't have the new motor. When I get motor changed, I'll tell you all about it. Does anyone know if I need to make a great effort to fill motor and lines with oil or will pto circuit fill it as soon as turned on. I can't imagine it taking more than 2 seconds to fill the whole thing. Any ideas?

 

[jrlichina]

You don't need to try to fill the lines or the motor, like you said it will fill fast enough. Just run it a bit then recheck your fluid level and you'll be good to go.

 

[Sedgewood]

Rick_Taylor: <font color="red"> Does anyone know if I need to make a great effort to fill motor and lines with oil or will pto circuit fill it as soon as turned on. I can't imagine it taking more than 2 seconds to fill the whole thing. Any ideas? </font>

In general: having oil to the bearings the first few seconds is critical. Many (all?) motors with a case drain hose have their bearings lubricated by the fluid in the case drain. The rule is to fill the case drain. I'd put as much oil in the case drain port as I could before hooking up the line. Pumps without a case drain I'd fill with oil before hooking up the lines. Then start and run slowly, unloaded, until the air is purged.

In your case: where you've just removed the pump and replaced it with a new one and the rest of the system is full of oil it's probably ok to just start slowly, unloaded, until the air is purged.

Happy motoring,
Sedgewood

 

[Rick_Taylor]

I received the motor Wed. afternoon and replaced it yesterday. That was NOT an easy proposition. First, for Duane: the center bolt holding the wheel and the setscrew are 3/16" Allen head. Suprisingly not that hard to remove. BUT, the wheel had grown to the shaft. After at least an hour of using a piece of 2x4 and a large hammer I was able to get it off with some help from WD-40 in the setscrew hole.

The motor is held to the frame by self-centering bolts. No problem with my air impact. The hoses were a problem. They can't come thru the steel strap on the stump grinder frame so must be dealt with by lowering the motor to the ground, with hoses attached. Unfortunately that left me trying to loosen hoses with nothing but my good looks and one wrench. VERY difficult. After I got the hose with the female connector off I could thread the male hose out through the strap. That allow the use of a large vise to clamp the motor into while loosening the hose. From there on it got quite easy. I used Locktite on all bolts to keep them in. Also, something that will offend some, but I don't use teflon tape on pipe fittings. I have had terrible luck over the years using it. I use the Permatex Red or Black high temp RTV on all fittings, plastic, metal, water, oil, anything. It has NEVER leaked after assembly and will come loose if and only if a wench is applied. I put an English Triumph engine togather with this stuff and it never leaked oil. That's much better than new! They leaked on the showroom floor.

The motor was filled with oil from the manufacturer with some plastic screw-in plugs so I left as much as possible in there. When I fired it up the first time, without the wheel installed, it made a bit of noise so I backed off the mounting bolts a bit. They must have put motor into a bind because it quieted up a lot. The wheel and shaft were sprayed with Lithium grease and the wheel went back with only a few small taps. It is a lot quieter that the previous motor.

Now, can someone tell me how a motor that is running in gallons of oil gall a bearing? It just doesn't seem very easy to do. The old motor only had maybe 6 hours on it. The stump grinder just isn't used that much.

Thanks everyone for your support. BTW, if anyone is looking for hydraulic parts of any type, checkout Baileynet.com. They sent a catalog along with the motor. They seem to carry just about anything hydraulic we'd ever need and their price on this motor was $119, vs. PT's price of $276.

 

[Charlie_Iliff]

<font color="red"> with nothing but my good looks and one wrench. </font>
With my looks, maybe the wrench wouldn't have been necessary. /forums/images/graemlins/grin.gif

Sounds as if things went pretty well, considering.
I echo your recommendation of Bailey. I've gotten their catalog for years. They've given me good advice on the phone, quick delivery and good prices.

 

[Sedgewood]

Rick_Taylor: <font color="red"> Now, can someone tell me how a motor that is running in gallons of oil gall a bearing? It just doesn't seem very easy to do. The old motor only had maybe 6 hours on it. The stump grinder just isn't used that much.
</font>

Could it have been commissioned dry? /forums/images/graemlins/tongue.gif

Sedgewood

 

[duane]

Rick,

Thanks for the info. I wonder if some debris went through the motor and damaged it?

Duane