Pressure Relief Block, Curtis plow

[J_J]

Did you look at the pics?

Apparently I did not see that pic. Was it there at the start of the post?

Someone said SA cyl were used. I do believe that is a DA cyl.

Getting old sucks.

 

[kennyd]

Give it up. You are wrong on this. I'm not going to sit here all night and debate with you. Guys from Jacksonville, FL need to be careful handing out snowplow advise. Some of us know a little more about the subject.

:laughing::laughing::laughing:Good luck with that!


To all reading: Note also that these cushion valves/crossover relief valves are also good to have an thumb circuits.

 

[Duffster]

Apparently I did not see that pic. Was it there at the start of the post?

Someone said SA cyl were used. I do believe that is a DA cyl.

Getting old sucks.

Do you think he is trying to put a crossover relief valve on the lift cylinder?

 

[SpudHauler]

Well it looks like I'll go with my #6 post conclusions.

Re-install the pressure relief block for the two sa left/right swing cylinders.

Good protection for shock loads.

I only took it off when trying out the 12v selector valve and didn't realize the benefits of a pressure relief block. And it was removed because the selector valve was out on the plow not in under the hood. When I switched this system from my old 900 to the 1100 I moved the selector in under the hood and forgot all about the relief valve. Until the other day when I spied it in my junk box.

I didn't mean to create such a flurry of activity. But all very educational.

What makes it a good choice for thumb circuits? Shock loads from the boom itself?

 

[kennyd]

What makes it a good choice for thumb circuits? Shock loads from the boom itself?

So the curl cylinder on the bucket cannot try to force the thumb to open, that could likely bend the thumb cylinder or the mounts where it attaches to the boom.

From your post #6:

So the relief dumps the pressure back to the other cylinder in this case and allows some movement of the blade instead of allowing things to get bent. Cool.

100% correct.

 

[PILOON]

I had one on a fisher plow.
Shure saved things whenever my driver hit a curb while plowing.
Most truck plows use 2 single action cylinders and the valve (crossover valve) would dump the excessive pressure load over to the other line.
The unfortunate thing is that only the leading plow corner is protected, i.e. if angled full right and U hit a curb with right corner of blade, there is nowhere for the blade to go.

If blade is square to the front, then both corners are protected.

Spudhauler: check your PM.

Quick note;
The valve in the picture looks to me as a straight PRV and not a crossover valve as a crossover would have 4 ports (2 per side)and the one shown can only have 2 from the PIX.

 

[SpudHauler]

The block does have 4 ports.

The other end looks like this one pictured here.

 

[SpudHauler]

Piloon, No PM.

 

[SpudHauler]

Well I got my pressure relief block back on the curtis plow and my welder finished the last modification to the a-frame. Plowed another 4" of snow this morning, works great.:thumbsup:

Thanks for all the input.