Wheres the best place to put Check valves?

[Rahstyles]

i have a vu4 set up and water trap between compressor and tank.. only 1 compressor.

[Oh Damn, it's Sam]

Anywhere between the compressor and the tank will be fine. Viair mounts their check valve at the end of the leader hose, which works well enough.

[NycCustomizer]

I agree with what's posted above. I always add a Check between the compressor and my water traps in case the trap leaks or is left loose. In somecases you may see checks installed between the tank and diaphragm valves. When installed there it prevents the fill valve from leaking back into the tank when the tank pressure drops below the bag pressure. This happens when there is a leak or when you are leveling a car with low tank pressure. VU4 manifolds don't require that.

[Alex@BagRiders]

Depends on what you are trying to do. Compressors already come with check valves installed on their leader lines although Viair's aren't the best. If you are trying to replace those, it is best to take off the current compressor check valve and install the new, upgraded one in place of it.

If you are trying to make your tank independent from the rest of your system, you can put a check valve on each supply line (between your tank and your manifold). This way, if you ever needed to do maintenance on your management, you can completely drain your tank/ take it out without airing your car out. Do not put check valves on the lines to the bags..

[TheNeek]

Do not put check valves on the lines to the bags..

Would be a funny prank though.

[Rahstyles]

Dont you need back pressure from the check valves to keep it closed? Also.. is it wise to put a check valve between tank and vu4 ?

[NycCustomizer]

Check valves are spring loaded. No back pressure needed. VU4s dont need any pressure on the supply side to keep it closed so there's really no point to add one between tank and manifold.

[Rahstyles]

if thats true then why did my bags leak out when my water trap broke.. which was between the compressor and tank?

[TheNeek]

if thats true then why did my bags leak out when my water trap broke.. which was between the compressor and tank?

leaking manifold?

[Rahstyles]

I highly Doubt the Vu4 Holding air in all bags.. IM shure it needs some back pressure... IF you pumped your bags and took out the inline tubes to the vu4 im pretty shure the air will bleed out from the vu4 .. with no back pressure..

If im wrong please let me know..

[Alex@BagRiders]

Dont you need back pressure from the check valves to keep it closed? Also.. is it wise to put a check valve between tank and vu4 ?

Putting a check valve on your supply line(s) between your tank and manifold is a good idea but it really isn't necessary by any means. It's more of a convenience thing if you want to work on your management/ tank without having your car air out completely.

Check valves are spring loaded. No back pressure needed. VU4s dont need any pressure on the supply side to keep it closed so there's really no point to add one between tank and manifold.

Most VU4s will need back pressure on the supply (tank) side of the system to stay closed. Usually they will just air one corner out, sometimes two. The thresholds of the valves don't seem to be consistent so when the tank pressure drops below the pressure in the bags, a valve will lift allowing air to back flow into the tank. Not all VU4s do this though and you may get one that doesn't lift valves but they don't seem to be as common.

[Rahstyles]

So does that mean mine is malfunctioning?

[Alex@BagRiders]

So does that mean mine is malfunctioning?

Nope, that's normal with the VU4.