Replacement engine options for a 720K?

BrownCoat

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Look up the specs for your engine .
The only important things are the shaft size and the height from the base to the shaft.....
If your hopper does have a flywheel PTO make sure you fit the blow out covers which your engine should have been fitted with.
If not buy a pair of them and cut the housing to fit them then most important, use them regularly to keep the cooling fins clean.

Gotcha. Ok, I'll check into that and what those places have to offer. I'm not sure what the "blow out covers" are. Mine has shrouds around the heads but I had to practically take the whole engine apart to get those off and clean the fins.
Thanks for your help.

I know you don't want to hear this but I like kohlor engines. I went threw 3 Kawasaki engines on a toro in less then 1000 hours. Went with a kohlor pro and after 500 hours put them on my other 3 mowers.
I have not liked Briggs since they stopped making the opposed twin.

I don't have anything against them, really. I'm a little miffed at how much you have to disassemble to get simple stuff off and some funky component placement issues. My main problem with them at the moment is the cost to replace one. I just don't have $1500+ to drop on a 20+ yo mower that still needs work in other areas. Still though, my dad replaced it with a Hustler and we all hate that thing. We'd much rather have the Grasshopper rolling again.

Thanks for the help. I'll take some measurements as soon as I can and see what's available. I was hoping that someone would say "oh yeah. this one and that one are direct replacements" :)
 

bertsmobile1

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part number 34 in the diagram below.
http://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/kohler-engine/command-pro-twin-ch-cv17-25-ch-cv620-750/ch18/ch18-62653-walker-mfg-18-hp-13-4-kw/blower-housing-group-6-24-262-ch18-750

They go over holes cut in the blower housing ( not shown ) in front of the cylinder heads .
You can remove them then blow out the debris around the cooling fins without removing the whole cover which for front PTO fittings is near impossible to do so never gets done.
When ever I get a horizontal shaft , flywheel PTO engine in for service I fit a pair of them.
You would not believe what I find under the covers, dead reptiles, rhodents, bird- rat- mouse nests, grass, clay etc etc etc.
Engine can not cool properly whith all that crud in there so it overheats, alloy gets soft, threads start pulling, valve guides shift in the head etc,etc,etc.
 

cambre

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These guys on this forum gives very good info. If I had to grade them I would put bertsmobile1 at the top. It would be hard to pick second as there are several who are extra good. I've owned a lot of different mower engines. Kohler is my favorite. I have a 26HP sv735 Kohler with 1775 hrs. that still runs very good.
 

173abn

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brother has the Kohler on his CubCadet.less than 30hrs on the motor and it has a cracked block.he did use JB weld and so far it's held...russ
 

BrownCoat

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part number 34 in the diagram below.
http://www.jackssmallengines.com/jacks-parts-lookup/manufacturer/kohler-engine/command-pro-twin-ch-cv17-25-ch-cv620-750/ch18/ch18-62653-walker-mfg-18-hp-13-4-kw/blower-housing-group-6-24-262-ch18-750

They go over holes cut in the blower housing ( not shown ) in front of the cylinder heads .
You can remove them then blow out the debris around the cooling fins without removing the whole cover which for front PTO fittings is near impossible to do so never gets done.
When ever I get a horizontal shaft , flywheel PTO engine in for service I fit a pair of them.
You would not believe what I find under the covers, dead reptiles, rhodents, bird- rat- mouse nests, grass, clay etc etc etc.
Engine can not cool properly whith all that crud in there so it overheats, alloy gets soft, threads start pulling, valve guides shift in the head etc,etc,etc.

Oh, ok. I see. That's what I think happened to this. When I finally got the covers off there was some packed in grass and oil which was blocking some flow. I'd say maybe 20% flow blockage. It still overheated though. Now it's like you said... all the metal is soft and useless and everything is stripping. Oh well. What can ya do. I'll have to pull the clutch off and measure that shaft and see if I can find an engine to match like you said to. I guess it's a crap shoot with these engines from what I'm reading. I'm not partial to any particular brand. I just need to get it mowing again. FYI - those Hustlers ride insanely rough unless your yard is glassy smooth. It's intolerable for someone like myself with lower disc problems.
 

BrownCoat

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These guys on this forum gives very good info. If I had to grade them I would put bertsmobile1 at the top. It would be hard to pick second as there are several who are extra good. I've owned a lot of different mower engines. Kohler is my favorite. I have a 26HP sv735 Kohler with 1775 hrs. that still runs very good.

brother has the Kohler on his CubCadet.less than 30hrs on the motor and it has a cracked block.he did use JB weld and so far it's held...russ

Extremely helpful people here. I'm used to motorcycle forums where everyone bickers and fights. Way nicer here :)

I guess you either get a good one or a bad one. I wonder if different engines are made in different plants or locations. Maybe that has something to do with the inconsistencies.
 

bertsmobile1

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Oh, ok. I see. That's what I think happened to this. When I finally got the covers off there was some packed in grass and oil which was blocking some flow. I'd say maybe 20% flow blockage. It still overheated though. Now it's like you said... all the metal is soft and useless and everything is stripping. Oh well. What can ya do. I'll have to pull the clutch off and measure that shaft and see if I can find an engine to match like you said to. I guess it's a crap shoot with these engines from what I'm reading. I'm not partial to any particular brand. I just need to get it mowing again. FYI - those Hustlers ride insanely rough unless your yard is glassy smooth. It's intolerable for someone like myself with lower disc problems.

It will either be a 1" or 1 & 1/8" and most likely the former.
Your only real problem will be the PTO height.
If you don't mind a bit of metal work you can get superceeded Briggs around that size for around $ 800 with a warranty .
Kohlers go about 20% more
Add another 20% for Kwaka and
Add 10% for a Vanguard

The biggest headache from changinf brands is finding a muffler to fit or modifing the existing one to fit.
These are specific to a particular mower and in many cases the only difference from one spec to another
 

NorthBama

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brother has the Kohler on his CubCadet.less than 30hrs on the motor and it has a cracked block.he did use JB weld and so far it's held...russ

Must be a Kohler Courage
 

173abn

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NorthBama...spot on.Don't know why they named them courage.where's the courage if you can only do 30hrs...russ
 

Mad Mackie

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Go to smallenginewarehouse.com, click on repower old equipment, click on Grasshopper, click on Grasshopper 720K to see their recommendations for repower.
 
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