Project 525EXI - 25HP Fuel Injection Repower

[bmsgaffer 2,043]

I am considering repowering my 522xi (for various reasons, but that's not the issue here) and I need the help of some experienced people. Sorry this post is a bit disjointed, I wanted to condense my thoughts without creating a bunch of new topics. 

 

I believe that the Kohler CH730 is a near direct fit for the Kohler CH22S that is in the unit, does anyone know this for sure? Best I can tell it is. 

 

My first issue is with the PTO shaft. The replacement engine I have a lead on has a (proper diameter) 4" long shaft with a 7/16-20 1.5" deep threaded hole on it, the one that came in the 522xi has a 3-5/32" shaft. I am hoping to run it as is, but it looks like it might come dangerously close to the battery, and I dont know if that 27/32" difference will cause the PTO belts to run all amok. 

 

How does the PTO attach to the driveshaft, just bolted straight on?

 

If it is an issue, has anyone cut a crankshaft before? If so, how? Will there be enough threads left for the PTO bolt if I don't have the crankshaft re-drilled and tapped?

 

I called one machine shop that rebuilt my K341 and they said they couldnt do it, but I may check with others. 

 

Thanks in advance everyone!

 

I changed the topic title to reflect my project that was based on the original topic. 

Edited October 15, 2016 by bmsgaffer

[slammer302 2,155]

I would have to look at the 522xi i sold my dad but you may be better off moving the engine back sum and making the drive shaft shorter than trying to cut the crank shaft down. But i think none of this will be necessary. I believe the electric clutch will be fine. Not a expert just going off my memories from the last time i pulled the engine out of a XI.   

[Callen 64]

I wonder if the cranks will interchange?

 

[bmsgaffer 2,043]

16 hours ago, Callen said:

I wonder if the cranks will interchange?

 

 

That is a fair question, but I do want to keep a totally assembled engine to sell if I swap, and I woild be leery putting a 800hr crank in an otherwise 0 hr engine. I might look at buying the correct new crank, but last I checked for another engine Kohler is pretty proud of their crankshafts.

[bmsgaffer 2,043]

 

I looked it up, the crankshaft MAY work with the engine I am looking at, but it runs about $250. 

[bslms 19]

Give Tulsa Engine Warehouse a try, give them your specs and if there is a CH730 with your specs they will find it.  Kohler made the 730 to meet hundreds of specs, there could very well be one out there that will work.  I have used TEW and they did very good work getting a replacement engine for our stump grinder.  I believe if you go to their website there is a form to fill out with your needs, fill it out and send it.  They will get back to you within a day or two after they do the research.. Good luck.

[Dennys502 244]

According to this they have the same dimensions. The shaft was sized by Toro to accommodate the clutch. I don't think we changed the flywheel side - just made the adapter to bolt the driveshaft to. The clutch will not be misaligned as it will seat against the back of the shaft. The difference in length will stick out of the front of the clutch. You will need to put some washers on the end of the shaft to take up the space. You could cut it off and drill and tap it if it is something you would be comfortable doing. I would drill it deeper before cutting it off. and the run the tap in after it is cut off.

Kohler engines.pdf

[bmsgaffer 2,043]

Thanks for the info Denny! I didn't know which end was most important for the PTO, so I'm glad to know its the back end that it seats against. If it all clears I will try to have a spacer made up, as I can't find anyone to drill, tap and cut a crankshaft (and I do not have the tools for it). In the end I think it is less than 1" difference, so I am hoping a decent spacer will suffice. 

[19richie66 17,495]

Any pictures of how the motor sits in the tractor? I was just wondering if it was driven off the flywheel side or pto side.

[bmsgaffer 2,043]

The hydro is off the flywheel side, PTO clutch is off of PTO side. 

 

 

[19richie66 17,495]

Got it. Thanks. I have never seen an XI series before. If you moved the battery forward a lil bit, would the one you're looking at fit in there? Wish I was close to you, might be interested in the ch22. I have a ch730 at the house but it came off of a stump grinder. The crank is 1-7/16" diameter by like 5" long. Going to put it on a frame and build something around it. I belive it will fit under a blackhood 

[bmsgaffer 2,043]

I think I wont even have to move the battery. It is less than 1" longer and there seems to be enough room behind the battery. At this point it looks like it will nearly drop in! (besides the PTO spacer, and maybe an exhaust modification)

[bmsgaffer 2,043]

Its like Christmas! 

[19richie66 17,495]

Very nice!

[shallowwatersailor 3,213]

I know that you won't use the muffler that came with the new engine. But will the air filter housing clear the hood? It looks to be about 1" to 2" taller.

 

Are those the ignition modules mounted to the air filter housing?

[wrightorchid 261]

looks like they are on a tab or something, so the air filter cover can be removed, at least when looking at the second pic (the one just below the big Kohler box).  That should have plenty of power for a long time.

 

[19richie66 17,495]

The fuses should be able to be relocated as can the module box, at least thats how they are on our z mowers. Not sure on the horizontal motors if the wires are long enough. The z turn fuses are mounted behind the crankcase and the module is mounted by the air cleaner housing. Sweet setup there! Nice for winter cold starts

Edited October 14, 2016 by 19richie66

[shallowwatersailor 3,213]

I was curious because on the CH22 they are under the shrouds.

[bmsgaffer 2,043]

30 minutes ago, shallowwatersailor said:

I know that you won't use the muffler that came with the new engine. But will the air filter housing clear the hood? It looks to be about 1" to 2" taller.

 

Are those the ignition modules mounted to the air filter housing?

 

Those things up by the filter are connectors for the oxygen sensor. The computer is right ahead of the starter with a big sticker, and each side has a small ignition module right below the spark plug (you can see where the wire goes on the starter side)

 

The overall height of the engine is actually almost 2" shorter because it just has a throttle body, no carb! And you are right, I will be purchasing a starter-side exit muffler that I will have to have a little pipe made up to exit where the existing one does now.

 

5 minutes ago, 19richie66 said:

The fuses can be relocated as can the module box, at least thats how they are on our z mowers. Not sure on the horizontal motors if the wires are long enough. The z turn fuses are mounted behind the crankcase and the module is mounted by the air cleaner housing.

 

I will have to see if the harness is long enough, this spec of engine is meant to be totally self contained, so the wires are pretty short but I would like to relocate to the firewall at some point.

 

Also, part of the optical illusion is that it has a "high clearance" muffler on it, the regular mufflers on the XI dont have that much of a height rise above the PTO. 

[19richie66 17,495]

http://kohlerengines.dirxion.com/app.php?RelId=6.7.0.19.3&bookcode=kea14flx

 

accessory catalog 

[slammer302 2,155]

Very nice. I like that it has a oil cooler.

[bmsgaffer 2,043]

5 hours ago, slammer302 said:

Very nice. I like that it has a oil cooler.

 

Indeed! I believe that there is plenty of room on the XI's too, so I dont know why they didnt spec the oil cooler. I may eat my words when I try to set the engine, but you can get the oil cooler and adapter to fit on any of these engines!

[bmsgaffer 2,043]

Got the CH22 off tonight and started to try to asses some of the differences. I didnt get a pic of it off yet, but I have more work to do tomorrow.

 

Up to this point there is only one issue that I have not accounted for, but it seems pretty easy to solve. The PTO stop bracket holes line up to untapped holes on the new block, but there is enough of the bracket that lines up with another set of holes that i should be able to re-drill the bracket and there will be no difference. 

 

I still have to purchase the new muffler, and have a spacer made up for the PTO clutch to account for the difference in shaft lengths. 

 

[bmsgaffer 2,043]

I made a bit more progress today. 

 

My first problem was that the shroud on the EFI engine was not setup for the spinning screen and flywheel driveshaft on the xi. I was able to order a shroud from an Exmark that still had the oil cooler cutout along with the proper front screen. As a bonus it also had the clean out plate kit already cut and included!

 

 

My second issue was that the holes I needed on the PTO end of the engine were not tapped, but they were pre-drilled. I was able to drill and tap them to get the PTO stop plate and the lower heat shield mounted. I had to trim the lower heat sheild to fit around the ignition modules and the engine mounted fuses.

 

 

The muffler I think is a bit lower than the stock toro muffler, but it seems like it will do OK.

 

Here's the stock spacer that is stuck in the end of the Electric PTO, but since my shaft is longer I will have to have the "shaft portion" of the spacer milled off and recessed a little bit to hold the clutch tight. 

 

I have to get the oil drain pipe and oil temp sensor installed and then I think I am ready to drop it in! I do have a bit of a wiring adapter to make up but I am hoping that wont be a big deal. 

 

I also got another fun delivery for my project:

 

Good to know that Miller ships them boxed up now, so no tweaked tires to relax before mounting!

[Dennys502 244]

Looking Good - that is going to be an awesome setup!

We tried some Kohler EFI engines for the Dingo - I was impressed.