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

Pressure gauge

September 30, 2022, 12:36:57 am

The green hand goes down from 120 to 60 lbs in an hour. Red hands stays steady. Rear of the coach goes down. Not sure which pressure tank controls breaks or aor shocks. Leaving for a 1000 mile
trip in a few days. May not have time to correct the problem. Not sure of I should chance the trip. Want to get the coach out of Bend, Or for the Winter. Both hands on pressure gauge does come up to 120 lbs in less than 10 tban.ins and stays at that level as long as the motor is running. This problem just occurred all of a sudden. Any advice is appreciated.

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Re: Pressure gauge

Reply #1 – September 30, 2022, 07:39:35 am

 Pedrodo,

With this being your first post welcome to the group.

Now would be a good time to swing by the $ store (yellow, green, orange) as all has big bottles of kids bubbles. While there pick up a spray bottle to put the bubble liquid into. This makes the best bubbles to detect an air leak. You must have a cracked air line, a hole in an air bag or air valve. Raise coach and block up the frame so you don't get squished incase the leak gets massive all at once. Listen for an air leak and spray every fitting that carries air to the rear looking for bubbles. Depending on what coach you have you need to check ride height valve and 6 pack for leaks.

It will help out to tell us what year and model coach you have as a FTX air system is quite different than a Unicoach or IH

Mike

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Re: Pressure gauge

Reply #2 – September 30, 2022, 08:43:20 am

One standard is 3 psi loss per minute:

http://dotmobileinspections.com/wp-content/uploads/2020/03/DME-Seven-Step-Air-Break-Test-1.pdf

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Re: Pressure gauge

Reply #3 – September 30, 2022, 09:25:59 am

As Mike says, would be nice to know what year/model coach is under discussion.

Assuming it is a model with 8 air bags and two brake pressure tanks...

I think the OP's big concern is not so much the overall rate of pressure decline but rather the fact that the rear brake tank pressure drops rapidly along with a commensurate drop in the pressure in the rear air bags, while at the same time the front brake tank pressure holds steady. 

Although not specified, if we assume both corners in the rear suspension fall at the same rate, then the air loss must be from some point common to all 4 rear air bags, and downstream from the protection valve on the rear brake tank (another assumption, since he said the pressure "goes down to 60 psi" which is approximately where the protection valve should activate).

HMMmmmm....

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