Buying Advice wish to buy a new suburu robin engine to replace current one

[MossRoad]

I see. I notice you don't have a heat shield either. The pumps are right underneath the muffler? In that respect, I might prefer the Robin/Subaru set up, but thats nice to see how the engineering changed from 2001 and obviously that year they built a durable, good running machine.Not that it would be anything significant, but I wonder if the newer PT-425 can lift more than yours, because of there being more weight in the rear of the tub? It looks like you have more available room to work on your engine than mine too?

There's a heat shield between the muffler and the engine. Heat travels up and out, so I don't think the muffler is passing much to those pumps. Mine's rated at 800 pounds lift. However, your's will lift higher, as there was a design change to increase the lift height. I do have pretty good room to work on the engine, however, I've never worked on it other than oil changes, air cleaner and I had to remove the muffler to change the battery, twice in 14 years! :laughing:

 

[ernemats]

I have a 1999 pt 422 with Subaru engine with 2,554 hours on it right now, have never had to do any work on the engine other than replace ignition coils and I think it runs as good as when new. It is set up differently than what MR's 425 with the Kohler engine is it has a pump in front of engine and one behind.

 

[ponytug]

Or, gasp, an air cooled Deutz?

 

[KMA]

View from other side.
View attachment 422900

One nice thing about the older Kohler equipped PT4xx is that cooling air is drawn from the front of the tub through the engine shroud and out the back past the muffler. There is a lot of openings in the rear of the tub for the heated air to exit. On the new machines, the air is pulled the opposite way, and I wonder if it's less effective since it gets pushed up against the front of the tub with nowhere to go. There could be some resulting turbulence that also negatively affects engine cooling. Just a thought...

 

[joshlee]

Sounds like a reliable machine. Good to hear!

There's a heat shield between the muffler and the engine. Heat travels up and out, so I don't think the muffler is passing much to those pumps. Mine's rated at 800 pounds lift. However, your's will lift higher, as there was a design change to increase the lift height. I do have pretty good room to work on the engine, however, I've never worked on it other than oil changes, air cleaner and I had to remove the muffler to change the battery, twice in 14 years! :laughing:

 

[joshlee]

Wow, that great! Maybe I'm not giving these Subaru engines enough credit?

I have a 1999 pt 422 Wwith Subaru engine with 2,554 hours on it right now, have never had to do any work on the engine other than replace ignition coils and I think it runs as good as when new. It is set up differently than what MR's 425 with the Kohler engine is it has a pump in front of engine and one behind.

 

[KMA]

I have a 1999 pt 422 with Subaru engine with 2,554 hours on it right now, have never had to do any work on the engine other than replace ignition coils and I think it runs as good as when new. It is set up differently than what MR's 425 with the Kohler engine is it has a pump in front of engine and one behind.

Which "direction" does your Subaru face? i.e., is the exhaust towards the front or back? Thanks!

 

[MuncyBob]

I have a 1999 pt 422 with Subaru engine with 2,554 hours on it right now, have never had to do any work on the engine other than replace ignition coils and I think it runs as good as when new. It is set up differently than what MR's 425 with the Kohler engine is it has a pump in front of engine and one behind.

On the other hand, I have a 422 with the EH65 that just had major overhaul done at less than 800 hours. I am fairly sure it was heat related and hopefully this weekend I will finally get the side mount fan installed.

 

[buickanddeere]

smallenginewarehouse.com is a treasure trove of replacement engines.