Pressure relief valve, update. ESSENTIAL ???

[TMB1320]

Pressure relief valve, update. ESSENTIAL ???

The documentation for the hydraulic chute motor kit that came with the used *NH 836GS snowblower does not include the pressure relief valve (crossover) that now appears in*the online docs. *Nor is it attached to motor. * The paper instruction sheet dated 08/08 for CNH part num 717172026 is absent BER3910018
pressure rv. *The online info clearly shows this part listed without mounting
hardware detail. *There must have been an update since '08 adding this part.

There looks to be some special tube type bolts that attach it to the motor
but again no detail. *Is this another "have to buy the assembly" including the
motor to get the special bolts? **

Another change I noticed was the flow restrictor size was increased from .047" to .063". *

The update must have been added because damage was occurring. *I can only guess where, but the real question is can I get this part and expect to get the 2 unlisted special bolts? * * * **

 

[J_J]

To provide a double relief valve, it should be mounted close to the hyd motor.

Here is one from Surpluscenter hydraulics. The ports are 3/4 NPT

Surplus Center - 3/4 NPT 30 GPM 1500-3000 PSI HYD CUSHION VALVE

Flow restriction change will change the speed of operation.

 

[TMB1320]

Close to motor. *The bulk of this wants me to locate up with *hyd quick connectors
I'm out if it can't do the job up there. *Care to explain why the interconnecting hose
to cylinder length affects performance. *My guess would be the hose expansion range( /_\ psi) *x length. *Relief should still work after the hose(x length) stops expanding.
Time delay perhaps, little more I can think of. *

Any way to tell what type of cylinder is on it from where the SINGLE flow
restrictor was located? Thanks for link. *There must be similar suppliers*
of the device, I'll check around. *

I discussed another solution with buddy. *Make the chute 360, no stops.
I'm in a cab, big deal. *Never need relief with that setup. *It's just operator after that. *Never every take the short cut to the other side with the chute!!

 

[TMB1320]

Putting fittings on. *Want the hose lettering to align with lift blower /pull, and chute cw (top view)/pull. * I can't tell from the drawings for the mb-
20 blb, *A Or B is the out/pressure when PULLING the spool.
I'll guess A, but not sure. Cmon guys, somebody must know how to read
schematics. JJ, my plan is to put some red reflecting tape on the radi of the front bends of the square
Chute, when I see red stop. I want at least 3 teeth before stop on the chute sprocket.
If I remember to check for movement for start up, I should be okay for now.
And my buddy says the spool valve has pressure relief built in. The valve does have one,
And I would like an opinion how reliable they are out of the box. The ad say preset at 1500 psi,
I believe. Should I be nervous here?

 

[Ductape]

My factory installed hydraulic chute rotator has no cushion. Though Kubota, it is made by RAD just like your NH blower.

 

[TMB1320]

No cushion. Well that's what I was trying to find out if the stop is violent given the spool
valve relief. Is no cushion a problem? What happens if/when you hit hard stop?

 

[Ductape]

When I hit the stop, the chute stops. Why wouldn't the pressure relief for the (loader) valve provide relief? FWIW, I wouldn't recommend cutting the teeth all the way around and making the chute 360* rotation. At least not unless all of your snow is very soft and stones don't exist where you live.

 

[J_J]

Putting fittings on. *Want the hose lettering to align with lift blower /pull, and chute cw (top view)/pull. * I can't tell from the drawings for the mb-
20 blb, *A Or B is the out/pressure when PULLING the spool.
I'll guess A, but not sure. Cmon guys, somebody must know how to read
schematics. JJ, my plan is to put some red reflecting tape on the radi of the front bends of the square
Chute, when I see red stop. I want at least 3 teeth before stop on the chute sprocket.
If I remember to check for movement for start up, I should be okay for now.
And my buddy says the spool valve has pressure relief built in. The valve does have one,
And I would like an opinion how reliable they are out of the box. The ad say preset at 1500 psi,
I believe. Should I be nervous here?

On the relief pressure, I would start out with the relief set low as from the factory. and if the chute turns OK, then leave it at that. If the motor stalls, bump up the pressure setting.

 

[TMB1320]

Ty for your comments. I may have just discovered why this blower doesn't look used.
The chute motor gear was installed with not enough clearance from the manual chute drive ring.
It was engaging both sprocket rings. Must have one he'll of a racket if it turned at all.
As I was removing the drive sprocket bolt, the motor became unstuck. I didn't investigate
further, as the sun was beating down hard. Adding a 5/16 spring washer to the motor shaft end
and reinstalling the drive sprocket. While at the blower had a quick look under door 2, reduction
Chain box. The master link keeper is on backwards, and it hadn't seen oil in a while.
Couple of capfulls of castoral 20/50 that has been in shed for 20 years is what it got. Left the keeper the way it was. Should I go back in the hot sun.?