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Discussion Starter #1 (Edited)
STX38 Yellow deck

I replaced my main drive belt, brand new, john deere not after market.

Install seemed to go ok, but now I have no clutch pedal.

Just goes to the floor.

l look underneath and I can see what the clutch does, it pulls the idler to let the belt slip for shifting.

Belt seems so tight that the clutch idler is actually in the position it should be if the clutch were fully depressed??

see drawing below-

With the belt off (during the switch) I could shift with ease, now even with the engine off, I cannot shift at all. ???

Looking for your expert advice.

Please advise thanks!

I know someone is going to say check to be sure belt is routed correctly. I really did check it a few times and I will go out and check it again right now.

Belt is "right" part number for the stx38, I think it is M74747 (from memory)

Do I need to let the belt stretch? (doesn't seem so but I never replaced this belt b4.)

 

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I don't have time right now, but when I get home from work this afternoon I will try to remember to look at my STX38 manual to see what the routing is. Is it too late to compare the 2 belts without major dis-assembly?
 

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Discussion Starter #3
I don't have time right now, but when I get home from work this afternoon I will try to remember to look at my STX38 manual to see what the routing is. Is it too late to compare the 2 belts without major dis-assembly?
yup, I was thinking about that too... I was going to compare at install, but figured the old belt is "so old" it probably would not be the same anyway... (wish now I had at least tried it probably going to have to come off...)

really does look routed properly??? BUT

any help is appreciated!
 

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Possibilities:
1) If you misrouted the belt the wrong way around the main drive pulley it may have consumed the slack normally left for the clutch linkage.
2) The belt routing through the idlers is wrong. Guessing that the green pulley in your drawing is the v-pulley (engages the V-side of the belt, not the back) it looks like the back of the belt could go over the red pulley 1st and then around the green. This is also assuming the tensioner is on the right side of the tractor.
3) The dealer gave you the wrong belt (unlikely but possible).
 

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Discussion Starter #5
Hey HOD, I appreciate the help.

start with #2 first: The drawing is correct at least as it is on my tractor, the drawing is with the tractor flipped over on its back with its wheels looking skyward... sort of like a belly-up tractor... and you looking down on it... The green pulley is the idler (clutch), the red is the V pulley.


#1 has my interest, just not sure what you are calling the Main Pulley, but I am assuming the one attached to the crankshaft. If we are talking about the same thing, all "seems" correct there. both a v-pulleys

#3 with the luck I have been having buying almost anything lately this one is all too possible :) I know the package the belt came in was the spec'd part number, I was too dumb to ever check to be sure the correct belt was in the sleeve however, I will go out and do that now.

any other insight is appreciated.

notice (per my drawing) how the green pully is "pulled back" that is how it shoud look with the clutch engauged... correct?

keep it coming! dying to post some before and after pics as it is coming alonge nicely, well if it worked that is... the paint looks nice :)

thanks m :trink40:
 

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#1 - yes. main pulley = crankshaft pulley. The belt can be misrouted and appear perfectly normal, at least on a 175 Hydro. When you throw it in forward and start backing up it all becomes perfectly clear :duh:

#3 was a ong shot - if you used a dealer belt I'd be surprised if they gave you the wrong one but I threw it out there because its not impossible either.

If you want a #4 maybe a tensioner spring came loose during the belt install.
 

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Discussion Starter #8 (Edited)
How's this?
Thanks for the reply.

OK, that is a pic of a known good and in the same orientation as my diagram. (bottom drawing) My problem per the diagram, is that my clutch idler is pulled way to the left (left as referenced in your pic) see top drawing, everything "appears" to be routed properly, the only thing think I can think of that would cause my perticular problem is a belt that is a bit short... :-(


Let me ask another question, of you or anyone that has changed this belt b4 as this is my first time.

With the clutch and brakes locked per install instructions, is it "hard" to get the new belt over the pulleys or shoudl it just slip over???

Mine was hard to get on, I am going out now and remove the new belt and compare it to the one I just un-installed, oh joy :)

any more ideas are greatly appreciated!
 

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Discussion Starter #9
GOT IT!

the idler on the transmission was 7" in diameter, the proper idler is 6" in diameter! And when you consider circumference I will get the 2"+ I was missing!

I mentioned in an earlier thread this was an inherited mower, sitting as junk on a piece of property I just bought.

a neighbor said "You will never get that thing going!" so I had to take the challenge!

I had no experience with JD and did not relaize how much they are worth used or how good the quality was.

going out the install the new tranny idler and give it a test!

the guy doing lawn maintenance just lost a job, as I now have a JD to do the cutting with... :thThumbsU

Pics to come! :thanku:
 

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Glad you got the problem figured out! Not sure if the picture helped or not but it's one reason why so many of us ask for pictures to help in diagnosing issues!
 

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Discussion Starter #11
Glad you got the problem figured out! Not sure if the picture helped or not but it's one reason why so many of us ask for pictures to help in diagnosing issues!
not this time, but I surely understand the pics thing!

just seemed that it was the last thing it could be after I compared the correct belt to the one I took off and the take off was LONGER!

*** weekend machanics... (oh, yeah I am one of those) :trink40:
 
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