John Deere 375 Backhoe

[abundyg]

I just purchased a 375 backhoe and after using it i was alittle disappointed I found that the backhoe couldn't lift the back of the tractor off the ground is this normal? I have the 3720 tractor with a cab and loaded r4 tires. Also does anyone know if there is a way to increase the pressure to gain more power out of this unit?

 

[Mechanos]

I have a 7 backhoe I recently bought and noticed that it's main relief valve is set at 1700psi. This seems odd to me since my tractor operates at 2700psi. I don't think it's set that low to protect the hydraulic components as much as it is to protect the hoe itself.... to keep from bending things, etc. Either that, or with the relatively light weight of the tractor, they're trying to keep the hoe from dragging the tractor around.

 

[abundyg]

Does anyone know if there is a different relief valve that can replace the existing to increase the pressure

 

[mguitas]

I just purchased a 375 backhoe and after using it i was alittle disappointed I found that the backhoe couldn't lift the back of the tractor off the ground is this normal? I have the 3720 tractor with a cab and loaded r4 tires. Also does anyone know if there is a way to increase the pressure to gain more power out of this unit?

I don't think it's normal , your hoe is made to fit your 3720. Should be able to lift it right off the ground. My backhoe is smaller then yours in size an weight, but will lift my tractor right up. Just my opinion.

 

[Mechanos]

Does anyone know if there is a different relief valve that can replace the existing to increase the pressure

In the case of the 7, there is a shim stack in the relief valve. To alter it's set point, you'd have to either add or remove shims or swap out the spring to a different rate. Either way, you'd better know what you're doing and be fully prepared to accept the consequences of your actions.

 

[Cocre]

On the 3x20 series the system relief pressure should be set to 2500 psi. This is set by adjusting the relief valve on the SCV. To increase pressure turn it clockwise. If you break something don't blame me. This should be done using calibrated gauges and such. Mine is set @ 2300 psi according to an uncalibrated gauge and the 447 hoe (same as 355 mostly) can lift my open station with loaded tires off the ground.

 

[dfkrug]

On the 3x20 series the system relief pressure should be set to 2500 psi. This is set by adjusting the relief valve on the SCV. To increase pressure turn it clockwise. If you break something don't blame me. This should be done using calibrated gauges and such. Mine is set @ 2300 psi according to an uncalibrated gauge and the 447 hoe (same as 355 mostly) can lift my open station with loaded tires off the ground.

Are you saying that your 447 does not have its own relief valve?! All the hoe
attachments I have owned or operated had their own RV.

Therein lies the problem, err feature. The hoe RVs are very often not set
correctly for your tractor. The 3x20s have a 2500 psi rated pump, so the
hoe should be operated at 2500psi.

Some hoes are only rated for 2000psi, so they are set near that value,
hopefully. But outgoing QA is not always good.

Since many hoe attachments are sold for unknown tractors, they have
their own RVs. It is certainly POSSIBLE that one does not, but unlikely, IMO.
Note that many hoes can be attached to the 3-pt and/or used with a PTO
pump system that has no RV of its own.

As for the OP's 375, his hoe's RV is set way to low, or the boom piston seal
is possibly blown. Even at 2000psi, all these hoe attachments, working
properly, can lift these CUTs no problem.

 

[cjdavis618]

There is a video on YouTube of someone selling a 3720 w/375 and he lifted it of the ground no problem and it was a cab model. I will try and find it. I looked at it this morning.

Also what rpm are you trying this at just be sure?

 

[CinderSchnauzer]

I just purchased a 375 backhoe and after using it i was alittle disappointed I found that the backhoe couldn't lift the back of the tractor off the ground is this normal? I have the 3720 tractor with a cab and loaded r4 tires. Also does anyone know if there is a way to increase the pressure to gain more power out of this unit?

Out of curiosity are you using Power Beyond to run the BH or 3rd SCV?

 

[shadow753]

I have a 3320os with a 47 backhoe and mine will lift the back end off the ground and move it side to side BOB