Kohler K361

[Eugen]

Picked it up today. Guy said he had lots of people interested, including higher offers. The tractor pulling crowd. Hope its head is not busted.

[thebuildist]

Thanks Noel, indeed I've come across all those reports about the valve seat problems. So, aluminum head with steel valve seat inserts. People say that if the head's damaged, bye bye engine, as those heads can't be found.

Not sure what to say about the fuel consumption, you know how it is, you want more power, you pay more.

I'd be skeptical of The engine needing to be trashed just because the head has gone.

If it got made, it can get fixed.

Bob

[propane1]

I wonder if it could be converted back to a k341?


Noel

[Jancoe]

Just doing a little poking around at the k361 on the net and it does seem to have its issues but given the issues it still seems like a desired engine. Came across a forum that people were referring work to this company. Seems they do alot of work to them. Just passing this info along.
http://gardentractorpullingtips.com/a1e ... headrepair

Sent from my SM-S906U using Tapatalk

[DavidBarkey]

The number one issue with valve seats in Aluminum heads is heat . Iron/ steel expands slower that aluminum but expands greater amount . So if it gets to hot , it will stretch the pocket it is in and come loose when cooled . This is metallurgy fact . Doesn't mater liquid or air cooled . Bronze is almost the exact same expansion rate making it a better choice . This is what happens to the Onan valve seat if run without oil filter seal . This also happen to all the other makes if the cooling system is plugged or is run lean and over heats . Some engines have better cooling that other so are less prone to it . The same can happen to valve guides in OHV engines if overheated due to cooling issues , typically mouse nest under fan shroud . This engine has a higher compression rate than it flat head counter part , so it will naturally run hotter . Making sure the head stays cool and run a slight bit rich will definitely help it out .
My 2 cents worth . You may keep the change .

[Eugen]

I wonder if it could be converted back to a k341?


Noel

I think the block is different, as it doesn't have valves like that.

[Eugen]

Just doing a little poking around at the k361 on the net and it does seem to have its issues but given the issues it still seems like a desired engine. Came across a forum that people were referring work to this company. Seems they do alot of work to them. Just passing this info along.
http://gardentractorpullingtips.com/a1e ... headrepair

Sent from my SM-S906U using Tapatalk

Thank you Evan, I know the site and since I like the Kohler engines, I've been using it quite often.

[Eugen]

The number one issue with valve seats in Aluminum heads is heat . Iron/ steel expands slower that aluminum but expands greater amount . So if it gets to hot , it will stretch the pocket it is in and come loose when cooled . This is metallurgy fact . Doesn't mater liquid or air cooled . Bronze is almost the exact same expansion rate making it a better choice . This is what happens to the Onan valve seat if run without oil filter seal . This also happen to all the other makes if the cooling system is plugged or is run lean and over heats . Some engines have better cooling that other so are less prone to it . The same can happen to valve guides in OHV engines if overheated due to cooling issues , typically mouse nest under fan shroud . This engine has a higher compression rate than it flat head counter part , so it will naturally run hotter . Making sure the head stays cool and run a slight bit rich will definitely help it out .
My 2 cents worth . You may keep the change .

This is good info Dave, thanks! It seems that there is at least one company that offers brass valve seats for this engine. If it turns out that the steel valve seats came off I'll try to find some brass to turn new seats out of brass. Same with the valve guides?

Tried to start the engine last night using some starter fluid spray, but no go. It does have spark. The guy who sold it said he was able to start it with gas down the carb throat. Now I'm really curious what's inside.

[DavidBarkey]

The number one issue with valve seats in Aluminum heads is heat . Iron/ steel expands slower that aluminum but expands greater amount . So if it gets to hot , it will stretch the pocket it is in and come loose when cooled . This is metallurgy fact . Doesn't mater liquid or air cooled . Bronze is almost the exact same expansion rate making it a better choice . This is what happens to the Onan valve seat if run without oil filter seal . This also happen to all the other makes if the cooling system is plugged or is run lean and over heats . Some engines have better cooling that other so are less prone to it . The same can happen to valve guides in OHV engines if overheated due to cooling issues , typically mouse nest under fan shroud . This engine has a higher compression rate than it flat head counter part , so it will naturally run hotter . Making sure the head stays cool and run a slight bit rich will definitely help it out .
My 2 cents worth . You may keep the change .

This is good info Dave, thanks! It seems that there is at least one company that offers brass valve seats for this engine. If it turns out that the steel valve seats came off I'll try to find some brass to turn new seats out of brass. Same with the valve guides?

Tried to start the engine last night using some starter fluid spray, but no go. It does have spark. The guy who sold it said he was able to start it with gas down the carb throat. Now I'm really curious what's inside.

Seats need to be bronze not brass and to that there are different grades of it . Do a compression test on it first . Wet dry . Should be over 100 psi.

[Eugen]

You know the Kohlers, they got the Automatic Compression Release, can't run a regular compression test. I'll think of something.