Cub Cadet RTZ 42 inch

[doug in missouri]

Low hour 258 hours,, but engine locked up.
Oil was changed before it was due. Every 25 hours, operator manual says every 50 hours.
Was using a NAPA Gold filter on it. Engine locked up 2 or 3 hours after an oil change. Was using Castrol full synthetic in it.
From the first day we owned it, bought brand new, it would smoke like crazy for 45 seconds to a minute. Not operator error, would discontinue choke as soon as it started.
Anyhow, it was a KOHLER 7000 series engine 22 horsepower. 2 cylinder.
Found a brand new engine from Surplus Center. But, it is only an 18 hp single cylinder. Will it work? Not so sure we want to put another KOHLER back in. DOUG
 

[doug in missouri]

[Jo Bird]

Mowers take a lot of power. Yes it will work, but no way I'd replace it with anything smaller. I had a similar situation with a Ex-mark mower, found this place in Ca. and bought a new one from them, very satisfied with it.
https://www.kohler-engine-parts.opeengines.com/index.php?main_page=index&cPath=781_68
They have complete engines and short blocks if you want to go that route.
 

[T.R.K.]

The mechanic in me wants to know why it locked up. Have you tried to turn it over with the spark plugs removed? I'm wondering if it has gas in the oil and a cylinder is fluid locked.

As far as the replacement engine goes, I would stay at least 20 hp. or over, being that the OEM thought it needed a 22 hp. And Hydrostatic transmissions are power hungry. You need the right diameter and length crankshaft on the replacement engine. And if you go with Briggs, you need a charging system with enough capacity to run your electric clutch. I say this because some of the cheaper Briggs engines have a low amp charging system that is not meant to power an electrical clutch. Low amp systems mainly power the fuel solenoid and recharge the battery.
 

[504]

THere was one of those Kohler's that had an oil cooler that would plug with dirt and grass. It was
near the oil filter. Might look for that,may not even be your model.A hone job ,rings might be all it
needs.
 

[doug in missouri]

Both spark plugs are out. Removed enough plastic to access the vertical shaft. Have tried turning it both ways, not even a wiggle. Engine seems to be locked solid. DOUG
 

[T.R.K.]

One other thing to check: is the electric clutch free to turn? Sometimes their bearings fail and the engine appears to be locked up but it is really a frozen bearing in the clutch.
 

[ztrmowers]

when was this unit last running and what did it do, did it smoke, make noise or just quit.
 

[tractorguy2]

I would check the starter is not jammed up in the ring gear.
 

[DR. EVIL]

I'd check with SMALL ENGINE WAREHOUSE, in Indiana, I think they're around Indianapolis, 1-800-321-6725. They offer all kinds of replacement engines, my Tractor Show Buddy bought a OHV V-twin Briggs 23 HP from them to replace the KT-17 Kohler in his 317 Deere. Everything to install the engine along with complete instructions came in the box. The old KT-17 wasn't one of Kohler's better engines either.
My 5 yr old Cub Cadet TANK LZ has 199.1 hours on it, same as you I did the first oil change early, and every other oil change at 1/3 to 1/2 the recommended 100 hours, used Rotella 15W-40 as the owners manual recommends, use the Kawasaki filter, and have never had a second's problem with the engine or mower.