# John Deere 4500 Compact Tachometer drops to zero



## tgillar (5 mo ago)

I am new to the site. I just got a John Deere 4500 compact tractor. Brought it home changed the hydraulic oil (HyGuard) and filter. Took it out to shred a little. Noticed the tachometer it will go up to about 2200 rpm. If you throttle up further the tractor revs up but the tachometer drops to zero. This is well below the PTO speed shown on the tachometer. Also the PTO runs but if it gets in under a moderate load the PTO cuts out. The previous owner (a friend) just had a PTO valve put in. 

I am not new to tractors. I grew up on my farm. Just thought I would see if someone had a place to look?


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## thedukes (Jan 9, 2022)

Take a look and see if it drives off a cable.

The previous models did.

Look under dash and around pump on upper left side of engine. For a Cable like a SpeedO cable.


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## tgillar (5 mo ago)

I am away from it right now. I do believe it is an electronic tach. I will check.


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## tgillar (5 mo ago)

Will I think I researched the Tach issue. It is aftermarket. So I think that might be the issue. The real issue now is why the PTO loses power when it gets under a moderate load?


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## sixbales (May 18, 2011)

Howdy tgillar, welcome to the forum.

See attached data sheet for your tractor from tractordata.com


https://www.tractordata.com/farm-tractors/002/9/6/2966-john-deere-4500.html



From the above, you can see that your tractor has an independent PTO, which means that your PTO is driven by a hydraulic actuated clutch pack. You will need to get a service/shop repair manual to learn how to check the actuating pressure to the clutch pack.


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## An Brown (Aug 15, 2020)

tgillar said:


> I am new to the site. I just got a John Deere 4500 compact tractor. Brought it home changed the hydraulic oil (HyGuard) and filter. Took it out to shred a little. Noticed the tachometer it will go up to about 2200 rpm. If you throttle up further the tractor revs up but the tachometer drops to zero. This is well below the PTO speed shown on the tachometer. Also the PTO runs but if it gets in under a moderate load the PTO cuts out. The previous owner (a friend) just had a PTO valve put in.
> 
> I am not new to tractors. I grew up on my farm. Just thought I would see if someone had a place to look?


It covers every single detail on yourJOHN DEERE 4500 4600 4700 TRACTOR Service Repair Manual . This manual significant in the treatment and fix. This manual went with the total document. By having a strong fix manual, you put aside money just as get the chance to experience DIY fix your own vehicle.


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