2001 PT425 Kohler CH25 Oil Leak - Pull The Engine

[MossRoad]

My 2001 PT425 developed an oil leak. About 1/2 a quart every 20 minutes. Can't seem to locate it, other than a pool of oil under the engine. So time to pull the engine, put it on a stand, clean it up, and run it to locate the leak.

Trying to avoid disconnecting hydraulic hoses.

Pulled the gas tank and fuel pump all on the bracket. Just 4 bolts and a hose clamp.


Pulled the muffler. 4 nuts. Didn't break the exhaust studs this time.


Pulled the battery.


Unmounted the hydroback assembly.
Disconnected the wiring harness and positive battery cable from the starter.

Disconnected the tram pump from the mount on the front.


Disconnected the PTO pumps from the engine on the rear.


Removed the 4 bolts that hold the engine mount to the bottom of the tub.


Started lifting the engine and found one (1) hydraulic hose that goes through the engine mount. Grr.


Pulled the right rear tire, cleaned the fitting, bagged it and pulled the hose.


Pulled the engine.


Took about an hour and a half. Overall, not too bad.
I'm going to get a cap/plug kit and pull the hoses off the pumps, reassemble everything after locating and repairing the oil leak, and put it all back in as one unit. That will be much easier.

 

[MossRoad]

Yuck!

 

[2manyrocks]

I was curious to see more of the detail of how these are put together. Lots of information in those pictures.

I had to clean a similar mess off my Terramite recently. Used a plastic paint scaper to scoop off the mix of caked, oily dirt without scratching the paint, and then wiped it down with paper towels that I burned.

 

[m5040]

Yuck!

View attachment 831636

I know, it looks so clean on the top!

What is that black cylinder shaped object at the end to the tram control cable?

 

[m5040]

Looking at your oil cooler hoses, you have to wonder if replacing ALL the original hydraulic hoses in the tub would be advisable? Wonder what the cost would be? Too bad PT doesn't offer a complete package, but maybe the price would scare everyone away.

If you find a good package for the hose plug fittings, please post the info.

 

[MossRoad]

I know, it looks so clean on the top!

What is that black cylinder shaped object at the end to the tram control cable?

That's the hydroback. My tram pedal is cable controlled. I do not know what is inside of that cylinder. All I do know is that the cable pulls or pushes it, and the hydroback then operates the direction lever on the tram pump. The bracket that it mounts to has slotted holes, so I'm guessing that's how you adjust it for neutral with all 4 wheels off the ground.

Maybe there's some spring dampening in that cylinder to lessen shock from treadle movement?

 

[MossRoad]

Looking at your oil cooler hoses, you have to wonder if replacing ALL the original hydraulic hoses in the tub would be advisable? Wonder what the cost would be? Too bad PT doesn't offer a complete package, but maybe the price would scare everyone away.

If you find a good package for the hose plug fittings, please post the info.

Yep. I've been keeping an eye on those cables for a few years. If I'm in this deep, I might as well look into replacing them.

Once it's all cleaned up, I'll do a thorough inspection of everything and replace what needs to be replaced. Then it'll be good for another 20.

 

[MossRoad]

As far as the plug and cap set....

'someone' on this forum purchased one, and I'm kinda hoping they'll chime in with details.

If not, I'll search TBN for it.

 

[arto98607]

I have a very similar design Vanguard 35 hp engine in a Vermeer stump cutter and am very interested to hear where the engine oil leak was once you have located it?

The oil filter/oil cooler setup would be the first place I would take a look at, followed by oil pan & crank seals.

 

[2manyrocks]

Lot of plumbing going on in there.

I don't know what fittings you have there. The Terramite has a bunch of 1/4 NPT stuff that can be capped with plumbing fittings so long as you don't let any galvanzing flake off into the system. Some other members found a set of standard hydraulic caps/plugs on Amazon as I recall.

It's begging for a diesel repower, too.

 

[arto98607]

Originally factory fitted Diesel model would probably be better choice but may be hard to justify the cost?

 

[MossRoad]

Lot of plumbing going on in there.

I don't know what fittings you have there. The Terramite has a bunch of 1/4 NPT stuff that can be capped with plumbing fittings so long as you don't let any galvanzing flake off into the system. Some other members found a set of standard hydraulic caps/plugs on Amazon as I recall.

It's begging for a diesel repower, too.

I dislike diesel.

Can't stand the smell of it if it gets on my clothes. And, I've never failed to get a gas engine to start in cold weather. The little CH25 Kohler has started as low as -15F with just a shot of starting fluid.

Diesels, on the other hand... I used to work with a lot of them when I worked at the airport back in the 70s and 80s. Gelled fuel was the biggest problem. All required pre-heating. All cost a lot more, etc.

Now it does not get as cold here as it used to, but I need it to start if it does. I don't want to have to treat fuel, pre-heat, etc.

When you think about a machine like the PT425, all it is is an engine spinning pumps. 25HP is 25HP, no matter what makes it. The pumps do not know. I'll lose traction and spin the tires way before the engine bogs down.

In my opinion... hahahahaha, I see no need for a diesel for my own uses.

For that matter, my first tractor was an IH2500b tractor loader. 8000# machine. 50PTO hp. Cab. Dedicated loader on the front and 3pt hitch on the rear. It was hydrostatic and had a gas engine.

Did I mention I dislike diesel?

 

[MTGreen]

Lot of plumbing going on in there.

I don't know what fittings you have there. The Terramite has a bunch of 1/4 NPT stuff that can be capped with plumbing fittings so long as you don't let any galvanzing flake off into the system. Some other members found a set of standard hydraulic caps/plugs on Amazon as I recall.

It's begging for a diesel repower, too.

Brass plumbing fittings avoid the galvanized flaking potential

 

[2manyrocks]

I dislike diesel.

Can't stand the smell of it if it gets on my clothes. And, I've never failed to get a gas engine to start in cold weather. The little CH25 Kohler has started as low as -15F with just a shot of starting fluid.

Diesels, on the other hand... I used to work with a lot of them when I worked at the airport back in the 70s and 80s. Gelled fuel was the biggest problem. All required pre-heating. All cost a lot more, etc.

Now it does not get as cold here as it used to, but I need it to start if it does. I don't want to have to treat fuel, pre-heat, etc.

When you think about a machine like the PT425, all it is is an engine spinning pumps. 25HP is 25HP, no matter what makes it. The pumps do not know. I'll lose traction and spin the tires way before the engine bogs down.

In my opinion... hahahahaha, I see no need for a diesel for my own uses.

For that matter, my first tractor was an IH2500b tractor loader. 8000# machine. 50PTO hp. Cab. Dedicated loader on the front and 3pt hitch on the rear. It was hydrostatic and had a gas engine.

Did I mention I dislike diesel?

Yes, but some day you may see the light.

 

[MTGreen]

Yes, but some day you may see the light.

I'm on the no-more-carburators crusade myself. Diesel or fuel injection from here on out. Not quite there yet but getting closer

 

[arto98607]

..................Snip......................


Pulled the muffler. 4 nuts. Didn't break the exhaust studs this time.

................Snip...............

I have switched to using brass nuts in all exhaust manifolds etc. I've had to take apart. On some applications I've used two nuts together for locking & extra strength.

So far it has worked out pretty good if or when having to reopen them, sometimes years later....

 

[ponytug]

As far as the plug and cap set....

'someone' on this forum purchased one, and I'm kinda hoping they'll chime in with details.

If not, I'll search TBN for it.

Here you go;

Amazon.com

It has been great to have for me.

All the best,

Peter

 

[MossRoad]

Here you go;

Amazon.com

It has been great to have for me.

All the best,

Peter

That's the one! Thank you.

 

[ponytug]

You are welcome!

Happy to help.

All the best,

Peter

 

[2manyrocks]

So how goes finding the leak?

FWIW, I've read a number of people on other websites who say that the Kohler CH25 is the best air cooled gas engine in that HP range.