pt 422 new engine

[porkysbbq2656]

Hi all got a quick ? I have a pt422 with a eh65 engine had any one replaced the eh65 with a new eh65, and if so what parts do I need from the old engine. The 422 I have the pumps in the front and rear of the engine, do I need to use the old flywheel or will the lovejoy bolt to the new engine just blew today at least 1200 hrs on it any input would be appreciated

[ernemats]

Sorry to hear about your engine. I also have a 422 with the same engine and setup on the pumps, it has almost 1,800 hrs. on it and still runs good. Several years ago I bought a eh65 replacement engine from another pt 422 owner who replaced his motor with a larger motor and I bought the old one he took out in case I ever needed it. I used the ignition coils off his engine to replace mine when they went bad. I can't help you much as far as what is needed to be reused when replacing the engine. Welcome to the forum.

[3238dpw]

Well there is always this. What you want to see starts around post 96

http://www.tractorbynet.com/forums/p...tering-10.html

[Tim_in_CT]

Do what kma did, and replace it with the fuel injected 27hp.

http://robinamerica.com/pfeatures.aspx?pid=223

Sounds like essentially a drop in replacement, with better winter starting performance. There have been at least three people here who are running the 27hp engine in a PT422 now.

I believe your setup is different, because you have pumps on front and back of the engine. Fortunately, the "flywheel stub shaft" accessory on your old engine is a universal attachment which you can use on any of the subaru v-twins, so you don't have to pay an extra $125 to get another one.

You may need to get another log-joy coupling, either because your old one has a worn insert, or because you might end up with a different size shaft on your engine then what you have now. Subaru sells a multitude of models with different shaft sizes.

[KMA]

Yeah, I'd recommend going with the EH72FI. It wasn't a difficult swap, and even though you have a slightly different setup you should be able to use the pics in my thread as a general reference.

http://www.tractorbynet.com/forums/p...eted-pics.html

The photos and description Vacuous_One posted in the thread Scott linked up should be more like what you will be experiencing. If shaft size is different for the coupling, contact Terry at PT. I think the newer models use the bigger shaft now and they have the proper couplers available. The only other difference is the extra fuel line back to the tank, and that the motor might get a bit hotter than the EH65. Otherwise the effort should be similar to swapping in the same model. I've had some issues with heat soak of the fuel line when mowing for extended periods since the upgrade. I have an extra fan turning on with the hydro cooler fan switch, but still lift the hood when shutting off and letting it sit... that seems to keep the engine starting up easily once I get back in the seat. You can still use the stock exhaust too. Check my thread for the company I purchased the engine from (equipatron.com). I had a good experience with them and the total price was $1880 with the shaft size upgrade (1 7/16") and shipping.

Good luck!

[BobRip]

Yeah, I'd recommend going with the EH72FI. It wasn't a difficult swap, and even though you have a slightly different setup you should be able to use the pics in my thread as a general reference.

http://www.tractorbynet.com/forums/p...eted-pics.html

The photos and description Vacuous_One posted in the thread Scott linked up should be more like what you will be experiencing. If shaft size is different for the coupling, contact Terry at PT. I think the newer models use the bigger shaft now and they have the proper couplers available. The only other difference is the extra fuel line back to the tank, and that the motor might get a bit hotter than the EH65. Otherwise the effort should be similar to swapping in the same model. I've had some issues with heat soak of the fuel line when mowing for extended periods since the upgrade. I have an extra fan turning on with the hydro cooler fan switch, but still lift the hood when shutting off and letting it sit... that seems to keep the engine starting up easily once I get back in the seat. You can still use the stock exhaust too. Check my thread for the company I purchased the engine from (equipatron.com). I had a good experience with them and the total price was $1880 with the shaft size upgrade (1 7/16") and shipping.

Good luck!

Do you see improved wheel motor torque?

[KMA]

Do you see improved wheel motor torque?

Yeah, I think so. It's not monumental, but there's definitely something there. The most noticeable was when I was using the finish mower while going up a relatively steep portion of my property. The new engine seems to get up the hill faster/easier than with the EH65, with no lugging. It's hard to separate perception from actual performance increases, but I'm fairly certain I can feel the slight power upgrade. I'm definitely not disappointed I chose this engine. My only issue was it gets a bitter hotter in the tub, but I don't use it any longer for finish mowing so the vapor lock problem doesn't show up. I may have been able to play around with fuel line routing, or something else to fix it. My best guess was the engine runs a bit hotter, and that the oil cooler is mounted right under the fuel lines. The EH65 didn't have that cooler.

[porkysbbq2656]

Thanks everyone for the input ordered fuel injected 27hp today I will poist pictures of the install thanks again.

[KMA]

Awesome! Best of luck and keep us updated.

BTW, Robin claims 28HP on the EH72FI, although I thought someone posted here that the 25HP EH72 power charts showed similar horsepower at the same shaft speed... 3600 (EH72) vs 4000 (EH72FI) or something like that.

Subaru Robin - Specifications