Engine swap! (and or upkeep)

PyhooyaBooya

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So I have a new MTD 42 inch rider with a 15.5 briggs and stratton engine. I don't need a new engine on this thing as of yet, but I seem to have horrible luck making things I get pre-owned last.

Lets say at some later date I want to do an engine swap. Am I opening a can of worms, or is it really not that difficult? Maybe even a different brand of engine.

Also, I put 10-30 into the engine, would putting some sort of oil stabilizer keep my engine better protected?
 

KennyV

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Engine swaps are not very difficult...
You will have to do a bit of measuring & some research to determine what will fit. But you ccan get almost everything you will need to find on line anymore...
It can be a fun project, so enjoy...
As to oil additives... If you are thinking of increasing your oil costs by adding things to it.... save some research time and $$ and simply switch to a good synthetic oil.. . I (and many others) run Rotella T6 in every engine I have... :smile:KennyV
 

mullins87

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Engine swaps in mowers are easy. As long as you stay within a reasonable horsepower range of the original engine, everything should bolt up. Beyond that it's just a matter of paying attention to such things like the exhaust location, which way the throttle linkage works, etc....

Oh, and shaft diameter and length should match or be very close. Otherwise you'll have to buy new engine pulleys.
 

PyhooyaBooya

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Engine swaps in mowers are easy. As long as you stay within a reasonable horsepower range of the original engine, everything should bolt up. Beyond that it's just a matter of paying attention to such things like the exhaust location, which way the throttle linkage works, etc....

Oh, and shaft diameter and length should match or be very close. Otherwise you'll have to buy new engine pulleys.

Well I sure would rather go up in HP. Throttle linkage I assume would be the most difficult part. Are most choke slides in the same position? Are there any more cables other than that? I can't think of any.
 

jmurray01

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Although swapping a lawnmower engine would be a nice small project, as long as your current engine is running well, you can easily keep it running well by changing the oil once every season and... That's it!

It is so easy to maintain an engine, especially a lawnmower engine as they are less powerful than motorbike/automobile engines, which means less wear on things like wrist pins that could go on bigger engines.
 

mullins87

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Well I sure would rather go up in HP. Throttle linkage I assume would be the most difficult part. Are most choke slides in the same position? Are there any more cables other than that? I can't think of any.


Almost nothing is impossible when swapping mower engines, and by that I mean as long as you keep the same shaft orientation, horizontal versus vertical. Things such as exhaust orientation can be a real limiting factor if you don't want to fabricate your own exhaust system. Throttle/choke slides can be anywhere, but that obstacle can be overcome with new cables. The mounting holes are easily changed with a bit of measuring and a drill. The shaft diameters can be different, depending on how big or small your replacement engine is, but you can find replacement pulleys at most farm supply stores. The physical size can present problems, but usually a little trimming of the hood will take care of that.

I've got an old Snapper that I'd love to put a 25-35 hp diesel in, right now it has an 18 hp Kohler twin. Now that swap will take some serious hood and frame mods!
 
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