Kohler SV590 19HP Question

Freddie21

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Hello Everyone, I obtained a mower with a Kohler SV590 19hp single on it. I'm pretty sure the connecting rod is broke, as the engine spins free and the piston does not move. I can push it in with a dowel. My question is, what are the chances I can install a piston and rod from another SV590 without changing the rings? The cylinder wall looks good on both engines. Tanx.
 

slomo

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Wear is wear my brother. Old piston will be out of OEM spec. Get a new rod and piston kit. Do it right. Sounds like a nice engine.

Course it's just a mower engine. Not going to Venus just yet. Now I'm confused on what to do LOL. It's your money so door number 1 it is.
 

bertsmobile1

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50:50 chance it will become an automatic mosquito killer .
Pull the engine down first and see what else needs attention
The bucket engine rarely tosses a rod but the counterweights were revised several times before they got one that stayed together .
 

Freddie21

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slomo- my thoughts were the same. Kit come with rings? If so, generic size?

Bertsmobile- can counterweights be reused or best to buy new?

Thanks guys
 

sgkent

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whether you can save the engine to put a new piston, rod, crank in it will depend on whether the connecting rod flailed around and smacked things (which is likely). I'd be saving for a replacement engine, but would still pull it apart and document the tear down to make it easier to put things back in the right place. This sounds like your first rodeo. Good luck but using a worn piston and worn rings in a worn bore isn't going to work. Last engine we broke a rod in scattered all over the race track in hundreds of pieces. There is a lot of energy in that rod when it flails around.
 

bertsmobile1

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Like every other part they have service limits
Some run in a track in the top plate so if yours is one of those, that needs to be well defined and not wallowed out.
I always replace the bolt that holds both sides together as they do tend to come loose ( all of the split counterweights have this problem regardless of the brand ) .
SO pull it apart. take lots of photos.
The only trick with there is the alternator stator .
You undo it and flip it aside as the plug does not fit through the hole the wires pass through
Scratch a line across the top plate & the throttle housing so it can go back in the same place
 

Freddie21

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Gentlemen, thank you all for the advice. I rebuilt a car engine back in the 80s and it was vey important to match the rings to the bore. I have not seen anything related to that or different size rings. Pistons come with rings attached. I am probably jumping the gun as I have not opened to see the damage. Just want to get an idea if I even want to go there. thought it would be a good cold weather project. Based on what I hear, I'm game to give it a try.
 

Freddie21

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Did some matching of part numbers and found that they both are a 94mm bore. Parts such as head, valves, piston, gaskets all have the same 20-xxx-yy part number where only the yy number is different. Any idea of wither the parts will be compatible or not. I want to use the sv620 20hp head with valves, piston with ring and the rod on the SV590 19hp.
 
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