What is this? (LSPV Valve)

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Grit dog

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^ Makes sense why it's sort of a jigsaw puzzle....because there are no other orientation marks.
I've gotten mine to work a couple times full power, trial and error, you can feel it "click" inside the valve at some point and before or after that is where it is free flow.
Just haven't been able to get a good mark and keep it there.
It's kinda frustrating, but like I said, mine works and its one less project, once i get it on the road, maybe can hook it back to the linkage and keep it open empty or loaded if I clock it right?
 

Grit dog

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@Blue Ox , do you have a better pic of the parts of that one you posted disassembled?
Can't see the cam and not certain how that spring doohickey on the plastic piece works
Interested how many degrees of rotation is "free flow" vs the prop valve in closed position.
 

Craig 85

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I’d toss it in the garbage except my brake lines are perfect and haven’t found or fabricated a fitting to simply swap it out without messing with the factory brake lines.

On my '87 K2500 back in the early 90's I disconnected the lines off the valve and made an adapter line to fit between the two OEM lines.

For my K30 here's how I did it. I don't recall if the K20's are set up the same. Once I removed the valve, I pulled the OEM brake line away from the frame and connected it throught the bracket for the valve.

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Grit dog

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^ Thanks for sharing.
Yes, it wouldn't be too difficult and the setup looks the same on the 3/4 ton.
It's just one of those, "if it ain't broke" type of things. I still haven't even got my frame as shiny as yours....much less optional projects!

That's the thing, if I could just get it clocked right, I could lock it in place with the OEM bracket which is also all in tact and would take mere minutes and cross it off the sht to do list!

Speaking of Hirsch. That's our sons hockey nickname...you know since all good hockey players have a nickname...Jonesey, Schmitty, etc.
He's Hershey or on the ice it's Hersh. For Hershberger.
 

Blue Ox

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@Blue Ox , do you have a better pic of the parts of that one you posted disassembled?
Can't see the cam and not certain how that spring doohickey on the plastic piece works
Interested how many degrees of rotation is "free flow" vs the prop valve in closed position.

It's more about setting the cutoff point than degrees of rotation for either event.

Here's a pic of another cam I have laying around. Obviously this one is in rough shape, but hopefully you can see the step in the cam.

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It's the step on the right side at about 2 O'clock that changes it from on to off as it turns counterclockwise. There's nothing you can feel as to where that is, which is why they used the plastic gauge tool.

The valve itself sits vertically on the centerline of the brass shaft, if that helps.
 

Grit dog

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^ perfect so it’s off for about 120deg.
 

Blue Ox

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No, it's the opposite. The cutout is the range where the extra proportioning is active. The high part of the cam locks it out.
 

Craig 85

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I still haven't even got my frame as shiny as yours....much less optional projects!

Speaking of Hirsch. That's our sons hockey nickname...you know since all good hockey players have a nickname...Jonesey, Schmitty, etc.
He's Hershey or on the ice it's Hersh. For Hershberger.

It's spray paint FYI. I had a clean California truck to begin with that was off the road for 10 years before I got it.

My Youngest son's nickname is Hershey, lol.
 

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