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Replacement Engine

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I am so confused!!  I DONT WANT to do a lot of re-work by installing another brand of engine. So I am looking at the Commands. So far researching here and GOOGLE says that the OE CH18 -62515 was replaced by the CH620 - 3078.

One company I contacted says the replacement would be CH680-3106 and another company I contacted says CH640-3126.

I assume these have different HP?!?!

all sources state a "rebuild" will cost like $600.00 and I found at BRANDNEWENGINE a command for $999.00 where EVERYTHING is NEW!!! what is all the difference with the different "specs"???

From looking at the pics the $999 engine doesn't have the hole drilled for the "pulse" fuel pump but it that's the only problem that doesn't seem too hard does it?

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The different "spec" numbers refer to the individual parts that make up that engine.  An example is the type of fuel pump, pulse vs the valve cover mechanical.  All the specifics of that engine.  

I'm not an expert by any means, but IMO, any 18 or 20 HP Command is an "easy" replacement with the "easy" depending on the spec of the replacement engine. 

I'm assuming you currently have a Command in your tractor - so you would swap the specific "Simplicity Spec" parts to the replacement engine.  For a Sovereign, the main parts to swap are the pulse fuel pump, blower housing/chopper screen and driveshaft adapter.   I would think the same would hold true for a SunStar, but I don't have any personal experience with a SunStar.  

I wrote a detailed description of converting a non-Sovereign spec Command to be one (spec 62513 - the Simplicity Sovereign Command spec, not 62515 you referenced above),  The post is titled "Kohler Triad Replacement - Command" and can be found in the Tech Tips forum or the Articles section. 

I have done two of these "spec" changes.  Both had plugged holes for the pulse fuel connection:


Note: All of my hands-on experience is with the older CH18/20 engines.  Maybe the newer "CH" engines are different and my advice is invalid.


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11 hours ago, CVSB10JCS said:

how did u open the hole for the pulse fuel pump?


ur right and I am wrong -  (spec 62513 - the Simplicity Sovereign Command spec, not 62515 you referenced above


It is a pipe plug. Remove with a allen wrench.

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