Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 11, 2025 ...

Air system question

November 13, 2016, 08:34:01 am

If the two foreward air tanks are drained, should the wet tank still retain a quantity of air, or is it depleted through the venting of the forward tanks?
Thanks, Mike

Quote Selected

Re: Air system question

Reply #1 – November 13, 2016, 08:56:54 am

Answer B:  Flow from the wet tank to either (or both) front and rear tanks is automatic, through check valves.  Draining either the front or rear tank will drain the wet tank.

In the reverse situation, if you drain your wet tank, the check valves on the front and rear tanks should retain the pressure in those tanks.  This is a good thing to verify once in a while - the check valves can become fouled with junk, and cease to function.  In that case, pull them off, clean them out, return to service.  Or replace, as required.

Quote Selected

Re: Air system question

Reply #2 – November 13, 2016, 09:04:28 am

Ok, thanks.  As you know, I am in the process of the six pack Rebuild; front is done, now starting on the rear, which is a bit harder to access the airlines.  Still getting air leak from both tanks overnight; about 50 psi in 15 hours.
Mike

Quote Selected

Re: Air system question

Reply #3 – November 13, 2016, 09:28:23 am

Mike,

You are not alone - I also have mystery air leaks which I cannot locate.  I can only offer general suggestions, like if you are losing air out of both front and rear tanks (at the same rate), then concentrate your sleuthing on the air lines and devices that use both tanks as their air source.  This requires careful study of your air system diagram.

For instance, the front and rear six packs each have their own dedicated air tank, so you can eliminate them and everything connected to them (unless both six packs were leaking at exactly the same rate, which would be rare).

Items on your coach like air horns, air step cover, parts of the braking system, etc. might be fed by both front and rear tanks.  The brake system portion of the air flow diagram gets pretty complicated and hard to follow (to me).

All you can do is keep plugging away, until your coach is tight enough that you are happy.  Every air system will leak a little!

Quote Selected

Re: Air system question

Reply #4 – November 13, 2016, 11:31:55 am

Quote from Chuck

The brake system portion of the air flow diagram gets pretty complicated and hard to follow (to me).

me two

Quote Selected