Replaced engine on my PT422

[BobRip]

I put a new Robin Subaru 22 horsepower engine in my PT422. I have an older PT year 2000 with pumps on both ends of the engine.
The most difficult thing was cutting the drive shaft to the correct length. It seemed to be a hardened steel and my Sawsall would not touch it. I ended up using the Dremel tool with a ceramic disc on it. I did finish the cut with the Sawsall. I used a lot of disc.
Also the shaft on the new engine was smaller than the old one and I had to get a smaller Lovejoy connector from Power Trac.
The old engine was using a lot of oil and it was hard to start. The new one starts so much better and seems to have more power.
I had about 1300 hours on the old engine and it was 18 years old. I also used It on slopes that were too steep at our Church. I always used synthetic oil and changed it every50 hours. I am glad that is done.

 

[MossRoad]

Nice summary. I'm happy to know the options when my Kohler's time is up. :thumbsup:

 

[ernemats]

Bob could you give more details on how you changed motors, I have a 422 1999 with pumps on both ends and I am in the process of changing motors. Did you have to disconnect the hydraulic hoses ? Terry told me the easiest way was to disconnect the hoses. I thought I could just unbolt thr pumos. I have a 22 hp Robin I bought 6 or 8 years ago off a member that replaced his with a larger motor.

 

[cqaigy2]

I bet it's nice to have replaced your failing engine!

I had just to opposite problem with the original lovejoy jaw for mine being too small, 1 1/8" that fit the robins 22hp and had to get one bored to 1 7/16" I found lovejoy jaws in a "farm store" in town that had a number of different sized shaft, none that would have worked for the kohler, but they ran about $8. I'm curios about how the pumps on both ends are arranged.

 

[MossRoad]

Here's some pics of my 2001 425 with the Kohler. PTO/Steering pumps behind the engine, variable volume tram pump in front of engine.

The PTO/Steering pumps are attached to the factory output shaft on the Kohler.
The VVP is attached to a stub shaft that comes through a hole cut into the fan guard. That stub shaft is a factory part from Kohler for those kinds of applications.

I'm gonna guess the 422 was set up the same way.

 

[jfh28]

great job Bob!.......you make it sound so easy.........Jack

 

[jfh28]

Here's some pics of my 2001 425 with the Kohler.

look how clean that engine is!!!!! if I didn't see the snow on the treads I'd swear it was in the showroom.......lol........Jack

 

[cqaigy2]

Thanks Moss.

I'm guessing the piece the VVP pump bolts to is mounted at the bottom of your tub, separate from the engine.

 

[MossRoad]

Thanks Moss.

I'm guessing the piece the VVP pump bolts to is mounted at the bottom of your tub, separate from the engine.

I'd have to look. :laughing: I'll be back in a bit.

 

[MossRoad]

Thanks Moss.

I'm guessing the piece the VVP pump bolts to is mounted at the bottom of your tub, separate from the engine.

The engine and VVP are mounted to the same plate assembly. If you look at the VVP pump picture, you'll see a thick black vertical plate between the VVP and engine. That vertical plate goes down and meets the end of the horizontal engine mounting plate. I'm guessing those plates are welded together, but can't see it due to..... GASP! DIRT!!! :laughing:

 

[Marks481]

If you look at the VVP pump picture, you'll see a thick black vertical plate between the VVP and engine. That vertical plate goes down and meets the end of the horizontal engine mounting plate.

I was wondering how the pumps bolted to the engine on the stub shaft mounted on the fan end, since the fan would get in the way of any bolt holes.

I guess I see why PT went to stacking the pumps; a lot less work then using both ends of the engine.

Would be nice, however, to put the exhaust manifold at the back end of the tub instead of in the middle over the top of the pumps (and right next to the gas tank).

 

[MossRoad]

Yeah, they have a little more cost with adding the stub shaft, but I'd guess they have a little more cost getting a VVP with an output shaft to drive the stacked PTO and Steering/lift pumps.

On you folks that have all three pumps in front of the engine, is there a bracket that hold up the pumps, or are they all hanging off the engine mount?

 

[BobRip]

I removed the gas tank with support bracket. I did not disconnect any hoses except the fuel line. Just unbolt the pumps from both ends of the motor and unbolted the engine from the support base (4 bolts). I also pulled the exhaust system off and removed the battery. The motor to support base bolts were a little difficult to get to. A neighbor, bless his heart, helped a whole lot. I borrowed an engine hoist from another neighbor, bless him to.
I changed the hydraulic filter while the engine was out.

It sounds easier than it was. But it was not real difficult. There is a connector you unplug for most of the electrical wires. Also you must pull the battery cable and a couple of more wires off the starter and remove the engine ground. Take a picture of the throttle and choke cables before you remove them.
I hope I did not forget anything here. Oh, don稚 forget to align the Lovejoy connector before tightening the motor support bracket bolts. Instructions can be found on Lovejoy web site.

 

[BobRip]

Here's some pics of my 2001 425 with the Kohler. PTO/Steering pumps behind the engine, variable volume tram pump in front of engine.

The PTO/Steering pumps are attached to the factory output shaft on the Kohler.
The VVP is attached to a stub shaft that comes through a hole cut into the fan guard. That stub shaft is a factory part from Kohler for those kinds of applications.

I'm gonna guess the 422 was set up the same way.

View attachment 563747

View attachment 563748

View attachment 563749

Looks very similar.

 

[MossRoad]

The way you write it up, sounds like an hour job!

Nice overview. :thumbsup:

 

[BobRip]

The way you write it up, sounds like an hour job!

Nice overview. :thumbsup:

I think more like 12 hours.
I had to wait over the weekend for the new Lovejoy connector.
Oh, I also spent over an hour cleaning the tub of oil, grass, sticks and what ever else. I started with a vacuum cleaner then compressed air and then a garden hose. I also painted the battery shelf.

 

[Marks481]

On you folks that have all three pumps in front of the engine, is there a bracket that hold up the pumps, or are they all hanging off the engine mount?

All of them are just bolted to the side of the engine. No support bracket.

 

[jfh28]

On you folks that have all three pumps in front of the engine, is there a bracket that hold up the pumps, or are they all hanging off the engine mount?

on mine the pumps are bolted together and then the rear flange is bolted to the engine mount....there are no brackets or seats it just cantilevers off the flange bolts
....Jack

 

[MossRoad]

All of them are just bolted to the side of the engine. No support bracket.

on mine the pumps are bolted together and then the rear flange is bolted to the engine mount....there are no brackets or seats it just cantilevers off the flange bolts
View attachment 563893....Jack

Interesting. I'd have thought there'd have been a support bracket. Thanks. Just curious as to all the different setups/generations that we've seen over the years. Hard to believe mine is 17 years old already.

 

[MossRoad]

I think more like 12 hours.
I had to wait over the weekend for the new Lovejoy connector.
Oh, I also spent over an hour cleaning the tub of oil, grass, sticks and what ever else. I started with a vacuum cleaner then compressed air and then a garden hose. I also painted the battery shelf.

I've noticed my battery shelf is also getting a bit rusty. Next time I remove the muffler to change the battery, I'll be scraping and painting as well.