Rubicon Locker Pump Function

[XCRN]

How do the factory pumps actually function when the locker switch is engaged?
Do they stay on the whole time and are regulated to 5psi or do they turn on and shut off when they hit 5psi and holds pressure?
How do they decompress to unlock, does the pump have an integrated valve to vent pressure when the locker switch is disengaged?

Instead of purchasing used pumps for $400 that look like they have been sitting in a lake for a few years I am looking at making my own setup. I am planning to use a small 12v air pump capable of 30psi and a boost pressure NC switch that is set for around 5psi to shut off the pump when it reaches operating pressure. The pump is like $5 and the boost pressure switches are about $40-80 so quite a bit cheaper than used factory lockers. Just trying to make this setup function as close to the factory lockers as possible.

 

[Alex01]

When the switch is activated, the factory pumps turn on and build pressure up to around 5 psi, then automatically shut off. They’ll only cycle back on if the system loses pressure. You should hear the pump run for just a few seconds, then stop. If it keeps cycling on and off, that indicates an air leak somewhere in the system.

 

[jjvw]

The Rubicon locker pumps shut off at whatever the prescribed cut off pressure is and will hold that pressure until power is removed from the pump.

 

[XCRN]

When the switch is activated, the factory pumps turn on and build pressure up to around 5 psi, then automatically shut off. They’ll only cycle back on if the system loses pressure. You should hear the pump run for just a few seconds, then stop. If it keeps cycling on and off, that indicates an air leak somewhere in the system.

Awesome, just what I was looking for! Any idea on when the lockers are turned off what happens? I am wondering if the pump on the outlet side any check valve has to hold pressure and a separate valve to release pressure when disengaged.

 

[jjvw]

Awesome, just what I was looking for! Any idea on when the lockers are turned off what happens? I am wondering if the pump on the outlet side any check valve has to hold pressure and a separate valve to release pressure when disengaged.

All you care about is whether or not the pump shuts off after couple/few seconds.

 

[Alex01]

Awesome, just what I was looking for! Any idea on when the lockers are turned off what happens? I am wondering if the pump on the outlet side any check valve has to hold pressure and a separate valve to release pressure when disengaged.

When you turn the locker switch off, the factory pump vents air out through its internal solenoid valve, releasing pressure and unlocking the differential. In short once you turn the switch to off its vents to the atmosphere.

 

[XCRN]

When you turn the locker switch off, the factory pump vents air out through its internal solenoid valve, releasing pressure and unlocking the differential. In short once you turn the switch to off its vents to the atmosphere.

Ok easy enough. I can probably find some inexpensive solenoid air valves and run a single pump for both lockers and run them to different switches for selectable lockers.

 

[JKP]

Just be sure you have the pressure well regulated or you'll blow the actuators in the axles.

The FSM under Resources describes how it all operates.

 

[XCRN]

Just be sure you have the pressure well regulated or you'll blow the actuators in the axles.

The FSM under Resources describes how it all operates.

Thats the point of the boost pressure switch I plan to use. Its normally closed under 5psi, when it reaches 5psi it will open the circuit. Plan is to run the 12v wire from the dash switch through the pressure switch to the pump. So when it hits 5psi the pump shuts off.

 

[XCRN]

This is my crude diagram.

 

[GATORB8]

Ok easy enough. I can probably find some inexpensive solenoid air valves and run a single pump for both lockers and run them to different switches for selectable lockers.

I would be a little picky on the solenoids and reasonably protect them (or carry a spare). On our recent Rubicon trip one of the rigs had the front ARB locker solenoid fail open (blow off valve stuck) and he had to do the run without his front locker.

 

[cpwolf]

This is my crude diagram.

View attachment 650883

There are threads on this, this is one https://wranglertjforum.com/threads/project-basketcase.67755/post-1258036

He put in an ARB, his comment, but he has pics too "Then used a low pressure regulator,manifold,10 psi blow off valve and arb solenoids with 3/16" emissions hose to the diffs. It works great and is set at 5 psi." His thought, he could use this ARB, and if his Rubicon goes out, he's ready to put an ARB locker in.

 

[cpwolf]

All you care about is whether or not the pump shuts off after couple/few seconds.

Doesn't he care that when he turns off the pump, it let's air out and disengages the locker? That was his question from the way I read it.

 

[XCRN]

Doesn't he care that when he turns off the pump, it let's air out and disengages the locker? That was his question from the way I read it.

I was questioning both situations, what happens when you flip on the locker switch and what happens after you switch the lockers off.

 

[cpwolf]

I was questioning both situations, what happens when you flip on the locker switch and what happens after you switch the lockers off.

Understood, Just that his response was all you need to care about is when you turn it on that it shuts off at 5 psi.

Just seems that when you turn it off you need a pump that lets air out so that the locker disengages as well, otherwise lockers stay engaged, correct?

 

[mrblaine]

Thats the point of the boost pressure switch I plan to use. Its normally closed under 5psi, when it reaches 5psi it will open the circuit. Plan is to run the 12v wire from the dash switch through the pressure switch to the pump. So when it hits 5psi the pump shuts off.

You may consider a pop off pressure valve set at 5-6 psi in case the electrical side malfunctions.

 

[mrblaine]

Understood, Just that his response was all you need to care about is when you turn it on that it shuts off at 5 psi.

Just seems that when you turn it off you need a pump that lets air out so that the locker disengages as well, otherwise lockers stay engaged, correct?

Most solenoid air valves vent to atmosphere when turned off. Or at least most of them I've messed with do.

 

[mrblaine]

I would be a little picky on the solenoids and reasonably protect them (or carry a spare). On our recent Rubicon trip one of the rigs had the front ARB locker solenoid fail open (blow off valve stuck) and he had to do the run without his front locker.

If you have ever opened one up, they are stupidly basic and likely got a spec of dirt in it. You can literally take one apart and rebuild the whole thing in 10 minutes.

 

[cpwolf]

Most solenoid air valves vent to atmosphere when turned off. Or at least most of them I've messed with do.

That's my experience, but if people are building something custom....I've been shocked before. I'm probably just jaded, having to tell folks at the company to check the obvious, that's what burns us repeatedly.

 

[GATORB8]

If you have ever opened one up, they are stupidly basic and likely got a spec of dirt in it. You can literally take one apart and rebuild the whole thing in 10 minutes.

I have not, but ARBs are going in this one, so I'll be sure to do a practice tear down when I set the system up.