Z425 Motor replacement

rubantin

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My mower stopped running today. When I turn it over there is a very loud double clunk with each rotation of the crank. So, I don't think I'll be taking the time to investigate. It has 800 hours and when I took the shroud off there was a lot of fur packed around the cylinders :(. So, I am sure it's toast. Anyways it is a 24hp 44L777-0144-G1 and I can't find a replacement for less than $1200. I found a new 20HP 40N877-0059-G1 that should drop in for $600 new.

What do you think?
 

Rivets

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I’m not sure of the compatibility between those two engines, but if you are patient I’m sure StarTech will see your thread and be able to help you out. I really don’t like the guy, but you can trust his recommendations. Really good head on his shoulders, but I think it might be cross threaded.
 

StarTech

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You don't want to drop 4 hp especially with 48" or 54" deck.
 

StarTech

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JD Parts don't even show a 42" for the Z425 model.

But they do show an Briggs 40H777-0152-B1 as a replacement.
 
Last edited:

rubantin

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I dread the idea of pulling that engine apart....
 

rubantin

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well? I just found a new 44S9770032G1 for $925... Would that work?
 

StarTech

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That is the Briggs recommend replacement for the current engine.
1686768459021.png
And you getting a fairly good discounted price and it is actually less what the short block costs me. Now you know why we don't rebuild many engines anymore.
1686768551166.png
 
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