[bikestuff]

Gang,

I have been inspired to find air leaks by the posts on here.  I don't usually fret about air leaks and fix them when I have time, however, I have found a problem that needs to be fixed ASAP.

From what I understand the 12V system will supply air to the slide seals, to the air door and to the toilet.  This is "backed up" by the 120V system.

In my case, If I turn off the 120V pump but leave on the 12V pump, I eventually lose the air pressure to the front slide seals and to the toilet.  The rear slide seals stay inflated.

Does anyone have an idea as to where to look?  I suspect that a check valve is blocked somewhere, but I can't imaging how to start to find the problem.

The 12V pump seems to be working properly.

Short Version:  The 12V pump does not supply air to the front slide seals.

Cheers,
bill

[rheavn]

"Short Version:  The 12V pump does not supply air to the front slide seals."

You have made your search easier by eliminating the 12V system.  I would put my leak down tester on the air line right before the shut off valve(if you have one) and the slide seal regulator.  This will tell you whether your leak is on the slide seal side, on the air source side, or both.  Then finding the leak is just a matter of following air lines and checking fittings & components.

Let us know what you find..................................

[bikestuff]

Steve,

I am not too worried about the leak..I will eventually find it. But why doesn't the 12V pump feed the seals? If I lose my 120V pump (has already happened a couple of times), the seals will deflate and let water in the coach.


Am I thinking about this right?

bill

[smagown]

Are your sure the 12v pump is pumping air?

[rheavn]

I misunderstood your post.  When you said the 12V pump does not supply air to the front slide seals, I thought you had eliminated the front seals from being supplied with air from the 12V air compressor.  If I understand you correctly you are saying that the 12V air pump is supposed to supply air to the front slide seals, but isn't.  

If the 12V air system leaks down below 60 psi when the 120V air compressor is shut off, then you have to look at a couple of possibilities.  When the main air system is above 60 psi, the 12V air system is joined with it. If the main air system has an air leak and leaks below 60 psi, then there is a check valve that is supposed to keep your 12V air system from leaking off.  If the check valve is stuck open then your 12V air system will leak down at the same rate as the main air system.  But in this case the 12V air compressor should keep the 12V air system between 40 & 60 psi unless there are leaks that it can not fill quick enough to keep up.  

Completely drain your air system with both air compressors off.  Turn on the 12V compressor & see if it can bring the system up to 60 psi.  This will tell you if your 12V air compressor is good. Verify that you have air in the 3 gallon air tank in the right rear wheel well.  If it does, then shut off the 12V air compressor and drain the system.  I would now put my leak down tool on the air line going to the front slide seal before the slide seal regulator.  Turn the 12V air compressor back on and see if it is supplying the slide seal with air.  If it does, then check which side is leaking.  If the slide seal regulator is not being supplied air pressure, then follow the line back to the air source.  The air source should be either directly from the 12V air compressor or that 3 gallon air tank in the right rear wheel well.  Now determine why air is not getting from the air source to the slide seal regulator.

Finding your air leaks will most likely eliminate your loss of air slide seal problem.  An air source blockage or a kinked air line is possible, but not as likely.

You have only referred to one 12V air compressor so I'm assuming you only have one. The newer coaches now have two 12V air compressors.

Let us know what you find...............................

[bikestuff]

That is exactly what I was hoping for! Thanks Steve. Will be back at the coach in a week or so, and I will come armed with my leak tool and a bunch of compression fittings to replace the push on ones.

I will report back with findings.

Thanks!

[Richard]

Bill,

you said you lose air to both the front seal and the toilet, did you not?

[bikestuff]

Yes Richard. No air to toilet when 12V only is on.

I *think* that the 12V pump is making air, but have not double checked that.

[Richard]

Check the pump first. If the rear seal piping is tight it could explain what you are seeing. Steve's excellent instructions will point you to the problem

[Chester Stone]

When I have the coach in storage, I shut off the 120v compressor and turn on the 12v compressor. At what pressures should the pump turn on and off? When the 120v compressor is running, the 12v gauge stop out at 60 psi to protect the down stream assets. Should that stop be reduced any?