alternator bearing and hydraulic noise on JD 750 tractor

   / alternator bearing and hydraulic noise on JD 750 tractor #1  

rmroper

Member
Joined
Aug 24, 2012
Messages
27
Location
Fort Collins, Colorado
Tractor
John Deere 750
I have a JD 750 tractor that has a noise coming from the alternator, Mt guess is that the bearings are going out. The dealer doesn't build build them, any idea how to find someone that can rebuild it? Perhaps some repair shop that rebuilds car alternators (if I can find one) ?

I also have a loud buzzing sound anytime the trctor is running, except when I am using the hydraulics (it stops when I raise / lower the bucket or tip the bucket).
It starts again immediately when I stop using the hydraulics.

Thanks for your thoughts.
 
   / alternator bearing and hydraulic noise on JD 750 tractor #2  
The generator (alternator) is rather simple on these tractos. Perhaps order the bearings from JD and have a local machine shop install them for you.

This place has a complete unit for sale. John Deere Tractor Parts: Electrical System Parts || Weaver's Compact Tractor Parts & Compact Tractor Salvage

FYI: P/N MIA10312 (old # CH15587)

Here is an explode view and part breakdown: OEM Parts

Bearing P/N from JD: M800123 Bearing old p/n: CH15994

Another source for new alternator: Alternator

Before messing with the hydraulics, I'd make certain the Hydraulic fluid is new and the screen cleaned, or if it has power steering to make certain the filter isn't old.

Good luck and let everyone know how you make out.
 
   / alternator bearing and hydraulic noise on JD 750 tractor
  • Thread Starter
#3  
Thank you for the information on the alternator, I will probably just order a new one.

The hydraulic filter and oil are both new, I don't think it has a screen.

The hydraulic noise started recently and goes away when the FEL is in use, but it comes right back when I stop moving the FEL. Kind of like the noise is there unless I am making the hydraulic pump work. Noise when FEL is not being used, no noise when FEL is being used. Could air in the hydraulic lines be causing this problem?
 
   / alternator bearing and hydraulic noise on JD 750 tractor #4  
JD 750 have a screen that is accessed from the side (Remove one of the rear wheels and it is there). The hydraulic filter was an add-on when the optional PS was added. It's simple enough to verify the screen is there and clean. Other than draining the hydraulic fluid again and your time it doesn't cost anything and is a place to start.

Is it the correct hydraulic fluid being used?

JD750 Screen.png
 
Last edited:
   / alternator bearing and hydraulic noise on JD 750 tractor
  • Thread Starter
#5  
Thank you for the information on the hydraulic screen, I will look into it, might be a little while as we just got 2+ft of snow in northern Colorado and the tractor is outside. I'm using John Deere hydraulic oil and the level is ok.

Thanks for your help.
 
   / alternator bearing and hydraulic noise on JD 750 tractor #6  
my 750 was making the same hydrualic noise and cleaning the screen did wonders. The hydraulics work amazingly now.
 

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