Large difference in compression on 2020 John Deere X380

Green machine

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  • / Large difference in compression on 2020 John Deere X380
Hi,
I just bought a used John Deere X380 with a 22 Hp Kawasaki. I checked the compression and the left cylinder as sitting on the Tractor,
measured 90 lbs while the right cylinder measured 75lbs. Oddly enough I had looked at a 2022 x350 I think it also had the same 22 Hp
Kawasaki and it measured 90lbs on left and 80 on the right. Does anyone know is this normal on this engine to see this discrepancy?

Thanks, Kevin
 

Bertrrr

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  • / Large difference in compression on 2020 John Deere X380
None will be exactly , those are close enough and it should run fine.
If you have one that is 50 percent lower than another you might have a problem - why were you testing compression ? is there a problem with it's running ?
 

bertsmobile1

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  • / Large difference in compression on 2020 John Deere X380
In the repair manual which is a free download they specs are 64 to 90 psi
Remember it could have a decompressor and a very slight difference in the valve lash left right will cause a big difference in compression.
As an old school long time engine fiddler with I am staggered at the number of people who do compression tests BEFORE they adjust the valve lash
Auto maintenance 101
set valve lash THEN check compression .
 

7394

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  • / Large difference in compression on 2020 John Deere X380
Just my .02 after valve lash confirmation to spec..

Then get engine up to full heat. & remove spark plugs, Open throttle WFO & then test compression, in each hole..
 

Tiger Small Engine

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  • / Large difference in compression on 2020 John Deere X380
Just my .02 after valve lash confirmation to spec..

Then get engine up to full heat. & remove spark plugs, Open throttle WFO & then test compression, in each hole..
Typically you are looking for no more than 10% differential between cylinders. In this case it is about 15%, so a little less than ideal.
 
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