Engine Kohler TH18s on 618 Grasshopper

Carbur6

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Does any one have this engine? Mine needs top end overhauled. I am not sure the number of hours on my engine but it is likely Very High.


CW4 Earnest Eakins

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ILENGINE

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Does any one have this engine? Mine needs top end overhauled. I am not sure the number of hours on my engine but it is likely Very High.


CW4 Earnest Eakins

Retired

The TH series engines aka triad engine had a bad habit of pulling the cylinder sleeves out when the engine didn't get proper cooling air flow. I know the oil pump and a few other parts are no longer available. Just replaced one with a command on a walker last summer due to a failed timing belt, and the oil pump gear would turn about 1/4 turn on the shaft from wear.
 

Dieselbob

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When I bought my 618 (2004), my dealer had a couple of used units with the TH engine (taken in trade) and he REFUSED to sell them, saying that if he sold me one, I would be uhappy with the mower, with him and with Grasshopper, and it wasn't worth it. I think he was going to re-power them with CH engines. My CH engine is approaching 1200 hours and runs like the day I bought it.
 

ILENGINE

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The Kohler OHC engine used was was called lost foam casting technology. the heads, intake manifold, cylinders, and upper crankcase was molded as one piece. The problem with the engine was the cylinders were bored from the bottom of the crankcase and then sleeves where then pressed into the cylinders. Under high heat situations the sleeves would creep downward, where the top ring would then grab the top of the sleeve and then pull it in to the crankcase breaking the rods.
 

relangle

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The TH series engines aka triad engine had a bad habit of pulling the cylinder sleeves out when the engine didn't get proper cooling air flow. I know the oil pump and a few other parts are no longer available. Just replaced one with a command on a walker last summer due to a failed timing belt, and the oil pump gear would turn about 1/4 turn on the shaft from wear.


I have a Grasshopper Model 618 purchased in 2000 and the engine is a Kohler TH18S. I purchased parts for the timing belt. I need help and instructions on how to set the timing on this engine. Can you provide instructions or a link on how to do this?

Thanks
 

bertsmobile1

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I have a Grasshopper Model 618 purchased in 2000 and the engine is a Kohler TH18S. I purchased parts for the timing belt. I need help and instructions on how to set the timing on this engine. Can you provide instructions or a link on how to do this?

Thanks

Same answer as given on your original post
Believe it or not Kohler have all of their repair manuals on their web page as a free download.
It is a bit klunky to navigate around so some prefer to use this site https://www.mymowerparts.com/pdf/Kohler-Service-and-Repair-Manuals/
 
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