JD X300 mower deck belt

   / JD X300 mower deck belt #1  

jd2210newbie

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I'm having problems with replacing my mower deck belt on a JD X300. The original broke. I measured it and it measures 141". All the replacements I find are 146". I've tried one of them but it twisted and hopped off. I suspect the extra length was part of problem. Googling I see lots of problems/bad reviews with replacing this belt. I'd like to start over with the proper length.
 
   / JD X300 mower deck belt #2  

seville009

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Sometimes the mower deck or mower itself will have a sticker somewhere (under the seat) that provides part numbers for any belts. If not look in the manual. It's possible that a piece of the belt is missing from the old broken belt (so maybe it was really 146").

one you determine that you have the correct belt, if it's still real loose, it has to be something with the pulleys, tensioner, etc.
 
   / JD X300 mower deck belt #3  

tomplum

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Before you go further, Deere has a fix for this that works. Ask about 42C deck belt failure Solution 116525. This assumes that you have the deck w/ belt # M154621 which is slightly more that 146". I've not seen a 141" deck belt.
 
   / JD X300 mower deck belt #4  

Doughknob

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Y not get one from your dealer?
 
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   / JD X300 mower deck belt #6  

JJT

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Your old belt was surely stretched more than an inch or two. I doubt the longer belt is the right belt.

The difference between new and old on my Kubota zero turn was more than 6". The OEM belt lasted 15 years and 600+ hours, I replaced it with an OEM belt. Funny thing, the Kubota belt for my mower comes in two different lengths, (4" difference). I got the short one, (probably original/old stock???) and it was a major pita to get it mounted. I picked up the longer oem as a spare for next time.
 
   / JD X300 mower deck belt #7  

MikePA

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Had TC25D, now JD X310
I'm having problems with replacing my mower deck belt on a JD X300. The original broke. I measured it and it measures 141". All the replacements I find are 146". I've tried one of them but it twisted and hopped off. I suspect the extra length was part of problem. Googling I see lots of problems/bad reviews with replacing this belt. I'd like to start over with the proper length.
Unfortunately, you did not include which deck you have. According to this site, Click Here, the X300 could have a 38 inch deck or a 42 inch deck. Note that you also ned to know your serial number in order to buy the correct belt. I buy almost all the parts I need for my X310 from these folks. Always a great experience.

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   / JD X300 mower deck belt
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jd2210newbie

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sorry, it is a 42" deck. i didn't know that there was something smaller. I see with and w/o tension handle. I don't think I have a tension handle just that bracket in the middle with the spring on it. It has a hole for a 3/8 square drive. I'm going to look around in yard again to see if somehow part of that belt broke off in the middle leaving me with only 141" since I see no references to a belt that short in any belt specs.

tks for all those links.
 
   / JD X300 mower deck belt #9  

MikePA

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Had TC25D, now JD X310
sorry, it is a 42" deck. i didn't know that there was something smaller. I see with and w/o tension handle. I don't think I have a tension handle just that bracket in the middle with the spring on it. It has a hole for a 3/8 square drive. I'm going to look around in yard again to see if somehow part of that belt broke off in the middle leaving me with only 141" since I see no references to a belt that short in any belt specs.

tks for all those links.
I clicked on each of the 42 inch links, there are only 6 of them.

M154621 146.244" This is the belt for the 42" deck on my X310.
M153160 156.614"
M172924 66.062"
M138583 115.000" (secondary drive belt)

Maybe it'd be easier to call greenpartsstore. :)
 
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