Air compressor keeps running

[PeterH-350LE]

Here is an odd one.
My Air compressor continues to run after the rear air bags are full, but the bags hold air for many days. I figure there must be a leak on the compressor side of the check valve, maybe a faulty shut-off relay. Any thoughts ?
I also noticed that on the tag axles Moho's, the Air bags will deflate once the tag axles gets pulled off the ground by the leveling system. I assume this to keep the rig leveled, in case the bags deflate slowly?
Thanks for your thoughts

[Inland RV Center, In]

Originally Posted by PeterH-87MH

Here is an odd one.
My Air compressor continues to run after the rear air bags are full, but the bags hold air for many days. I figure there must be a leak on the compressor side of the check valve, maybe a faulty shut-off relay. Any thoughts ?
I also noticed that on the tag axles Moho's, the Air bags will deflate once the tag axles gets pulled off the ground by the leveling system. I assume this to keep the rig leveled, in case the bags deflate slowly?
Thanks for your thoughts

Peter.

Several things could be the cause.

The air supply line, before the check valve, could have a leak.

The pressure switch could be bad.

The compressor might be worn out if it cannot bring the pressure up to the pressure switch rating.

If the tag axle is off the ground, the air pressure in the bags, will drop to minimum, as the leveling valve is sensing that the tag axle is too high.

Andy

[bkahler]

Originally Posted by PeterH-87MH

Here is an odd one.
My Air compressor continues to run after the rear air bags are full, but the bags hold air for many days. I figure there must be a leak on the compressor side of the check valve, maybe a faulty shut-off relay. Any thoughts ?
I also noticed that on the tag axles Moho's, the Air bags will deflate once the tag axles gets pulled off the ground by the leveling system. I assume this to keep the rig leveled, in case the bags deflate slowly?
Thanks for your thoughts

Peter,

Our 310 had the same sort of problem when we first bought it. It was the check valve. After replacing it the bags would stay up for a few days and the gradually deflate. That problem turned out to be in the leveling valve (only one valve on a 310) itself. If your air bags are somewhat old you might also want to check them for leaks.

I'm not sure how the wiring is configured on the 1987 345s but if it is anything like it was on our 310 and if you haven't already done so one thing to consider doing is reworking the power feed for the air compressor.

Apparently on our 310 the air compressor ran for long periods of time and had such a high current draw that it melted the connectors in the fuse block on the dash. Same thing occurred with the dash A/C fan fuse holder and connector.

Anyway if you're interested I can provide you with a sketch on how to rework it so power for the air compressor is drawn from the coach batteries directly.

Brad

[92landyacht]

Normal for the air to dump when the TAG wheels are off the ground.

[PeterH-350LE]

Thank you for all the replies. I finally got around to moving the mattress to gain access to the compressor space. Now, I feel really stupid, because the noise i heard was not the air compressor, but it was the electric fuel pump instead.
I may have to mount the pump on some rubber to keep it from making such a racket.
The compressor I found is a new Pacific Scientific (Thompson) TA 3101DC rated at 1/4 HP and it was installed very professional (thank you Dennis!!) with new heavy gauge wiring (they draw like 26 amps).
1 more item off the todo list