HDJ80 LSPV

[bugs007]

Hi all.

I purchased a new genuine LSPV through Amayama and have noted the piston on the device does not move. Tried grabbing it with long nose pliers but it wont move either in or out. Is this normal ? Does it require fluid pressure once installed to move out ? I removed the rubber bungs which were in the fluid line threads but made no difference.

The FSM states the valve piston should move down smoothly when pulling down on the load sensing spring (see photo) when it is installed but I cannot see how it can do that it seems stuck. I assume it just rides on the spring.

Have attached photos of the front and rear and looking down at the piston.

Unsure if I have a faulty unit or not. Could anyone who knows please advise. Thanks.

 

[Malleus]

I've never been able to move one without using the sensing arm. I'd think it's OK.

 

[NeverFinis]

Watching because I would like to know. I replaced my LSPV years ago, and then the truck sat. I assumed it was bad because of no movement of the pin, and bought another one. I haven't installed the new one yet.

 

[bugs007]

Watching because I would like to know. I replaced my LSPV years ago, and then the truck sat. I assumed it was bad because of no movement of the pin, and bought another one. I haven't installed the new one yet.

Can you move the pin in your new one ? I tried to on mine using long nose pliers it would not budge.

 

[NeverFinis]

Can you move the pin in your new one ? I tried to on mine using long nose pliers it would not budge.

Nope. The pin doesn't budge with needle nose pliers. They slip off before any movement.

 

[bugs007]

Nope. The pin doesn't budge with needle nose pliers. They slip off before any movement.

Same as mine. Ok lets see what others have to say about this whether normal or not.

 

[bugs007]

Found this video where you can see the piston moving as he bleeds the LSPV. It likely needs a lot of pressure to move

 

[NeverFinis]

I just checked my original LSPV that is currently installed.

The pin does come down when the brake pedal is pressed. It happened only once with the engine off, but did repeatedly move with the engine on. I think this might be because there might be air in those lines.

I will hold off on replacing it for now as it seems to be working as intended, just I need to do a better job at bleeding.