So thanks to my new found leaks, (https://www.foreforums.com/index.php?topic=43761.0) I'm unable to build enough pressure to get one corner of the coach high enough to insert safety stands. I'm only off by about 2 inches so I think the solve here is to temporarily turn up the pressure at the governor to compensate for the leak-down. Then I can slide under and fix those leaks.
My question is, how high is too high? 150psi? 200?
The alternative is to have a couple more safety stands cut at a shorter length but that's a bigger hassle.
Your maximum air system pressure should never exceed 150 psi. You should have a safety pressure release valve on your wet tank which should open at approximately 150 psi. If it opens it will be very loud.
Don't ask how I know.
I set mine @ 150psi.
The governor pressure won't go above the front air bag regulator set pressure which is around 70 psi. I believe.
The leaks are before the front tank and why I can't get one of the front bags all the way up so I don't think I'm hitting the top end of that regulator.
You need volume to compensate for the leaks not pressure. Do you have a 120 volt air compressor you could put in the air fitting on the coach? I have a male to male fitting for emergencies like you are having.
So you are saying your D2 governor is set to cut out the air compressor at 150psi? Your dash air gauges both read 150psi when your air dryer purges?
I don't have the fitting. I've been meaning to make a connector with inline air dryer for a compressor but haven't yet. Maybe it's time
I think Elliott is talking about his D2 governor...unless I completely misunderstood his question.
If your air compressor is cutting out at 130psi that is plenty of pressure to raise both ends of your coach.
If it is a front corner that will not reach full height, you could try raising the setting on the front 6-pack air pressure regulator. Normal setting is 60-65psi. Raising it to 70-80psi won't hurt a thing.
That is what I assumed also. Raising the pressure won't compensate for the cfm loss due to the air leaks very much he needs more volume or cfm.
Yes.
Easier to inflate tires
Elliott,
Just to be clear - is it a front corner that will not go up high enough?
Are you able follow the procedure below all the way through the 4 steps, or are your air leaks preventing you from doing so?
1. Running the engine with coach at normal ride height, let air pressure build up until the dryer purges (compressor cuts out).
2. Hold down the RAISE button. The air pressure on your dash gauges should drop down below cut-in pressure as the coach goes up.
3. Continue holding the RAISE button until the air compressor cuts in and air pressure comes back up to cut out pressure.
4. When compressor cuts out and dryer purges, the coach is as high as it is going to go. Turn ignition switch off, THEN release RAISE button.
At this point, if all 4 corners of your coach are not high enough to insert your safety stands, then you have some other problem. It is not lack of air pressure OR air volume (cfm) that is causing the problem.
OK... It's your coach, so DWMYH.
If you are going to run your air system at 150psi on a regular basis, I would recommend checking the safety pressure relief valve on your wet tank to ensure it is functioning properly. If it is dirty or corroded it may not open at the designated pressure. The opening pressure should be indicated on the valve body.
Safety relief valve wet tank (https://www.foreforums.com/index.php?topic=41925)
Not to mention compressor life will be reduced being operated at its upper range. And this comes with the added fuel to run at higher pressures and extended run times.
It's my front right corner that won't go up high enough. The coach isn't perfectly level and this is the highest corner by just a little bit.
I follow that process to raise my coach normally and it works fine. Currently, when I hit RAISE all three corners go up and the forth doesn't quite make it to full height, regardless of how long I try. I don't THINK I've heard the dryer's purge valve when raising the coach but I do when in travel mode. Prior to it sitting for a couple months, I was raising it all the time without issue in this exact spot.
I'm going to get out there tonight after work and turn the governor up to 150psi and see if that does the trick
The reason I would wait for the compressor to cut out (Step #4) is to insure that the leveling system has full max system air pressure (120-130 psi) to work with. ALSO, if the air compressor cuts out, it means the compressor is putting out more air volume than is being lost through your leaks. In that case, the leaks are not preventing the coach from reaching full height.
The pressure to the front 6-pack during manual leveling or using the RAISE button is controlled by the 6-pack pressure regulator. For most coaches, having this regulator set at 60-65 psi provides plenty of pressure to insure full air bag extension. However, there have been cases when a member reported having difficulty with the front end raising, and increasing the setting on the regulator seemed to solve the problem.
It wouldn't hurt a thing to try raising the regulator setting to 70 or 80 psi and see what happens.
See threads below for some old discussions on "What the heck is the purpose of that front pressure regulator?"
Air Suspension Pressure regulator (https://www.foreforums.com/index.php?topic=43015.0)
Six pack left front not raising (https://www.foreforums.com/index.php?topic=41631)
air leaking, what is this? (https://www.foreforums.com/index.php?topic=37314)
The front regulator is under the coach though, right? :'(
That WILL NOT HELP. That adjust tank pressure, not pressure to the front air bags.
Remember, only one ride height valve in front.
The two in the rear control left/right height.
Yes - under the front end, tucked up near the two air tanks. Looks like a common regulator on shop air compressors. Has a adjustment knob - gauge shows set pressure.
If you have a bottle jack you can raise the frame to insert safety supports.
My issue is that the leaks are after the rear tank and before the front tank. My hypothesis is that they're severe enough that the front tank isn't building enough pressure to get the front bags all the way up. I'm hoping increased pressure in the rear tank will translate to adequate pressure in the front tank..
I don't know what you are calling your "rear" tank. Do you mean the wet tank?
You don't have to guess what the pressure is in your front and rear brake tanks - just look at your dash gauges.
If your dash air gauge shows 120-130 psi in the front brake tank, then air
system pressure is not your problem.
As mentioned above, the front 6-pack regulator will determine what pressure goes to the front air bags.
Rear brake tank.
Pressure in both gauges reads at 120psi before I hit raise. Once I hit raise, they almost immediately drop to the cutoff around 75psi. Not sure if the front gauge ever gets back up to 120psi as I'm hitting "raise'. That's something I'll check tonight.
If your D2 governor is set to cut out the air compressor at 120-130psi, then the compressor should cut in at about 90-100psi. Your dash gauges should never get down to 75psi during the RAISE operation.
Your HWH low air pressure alarm (light or beeper) should go off when system pressure drops below about 80psi.
However, even 75psi in the front brake tank should be sufficient to raise the front end of the coach (as long as your front brake tank protection valve does not close).
You just need to make sure that pressure is getting
through the front pressure regulator, through the 6-pack manifold, and on to all 4 air bags.
Hold in the raise and see if pressure on gauges builds. If it holds and does not build, then let off raise until pressure is up again. Once pressure is up hit raise again, then repeat until air bags are full.
My "raise" button is latching. I just click it once and it stays in the raise mode until I click a different button.
So here's what I know:
1) I put coach in high idle and get tanks completely filled. Wait until I hear the purge.
2) I put it in raise mode and let it run. At this point pressure in the front gauge drops by about 25 psi almost immediately. Coach begins to raise.
3) let coach raise until I hear purge again. Both tanks back at "full" (I tried it with a few different governor settings from 120-150psi)
4) all corners but the one in question extend fully like I would expect, front right corner continues to not fully extend.
It does not matter how long I wait, that one corner just won't go up all the way like it used to. No change in behavior if I adjust the governor to 150psi like you guys suggested.
AFAIK nobody (in this thread) suggested you raise your D2 governor setting to 150psi. One member did say he runs his coach at that pressure. That was a comment - not a suggestion.
Take a look at the air pressure regulator for the front 6-pack. If it is set on 60psi try raising it to 70 or 80 or 90 and see if that helps.
You misunderstand my comment. Changing it to 150 psi had no affect. That is exactly the results you guys predicted.
I can't get to the regulator for the front six pack because it's under the coach, and I can't get my safety stands in.
I'm going to play around with positioning of the coach and see if I can get it a little more level. If not I'll just bite the bullet and go have a couple more safety stands made at a shorter length
Do you have some blocks that you can drive the front up on to get some working clearance?
Yea I do. It's probably enough to get me to the regulator, just not to do much other work. Good idea
On a side note, other one of my %#*@ing good year bags failed internally after six months.
Use a bottle jack to finish raising the right front then put in the safety stand then adjust the regulator for the front 6 pack. If after adjusting the regulator it still won't raise it could be caused by the raise solenoid valve or maybe the check valve in the 6 pack.
Got it up on ramps and slid under. I can't even read the regulator's gauge, too much gunk on the inside of the class. I've got enough room to work on my back though so I'm just going to start replacing everything including the regulator. Somebody put one of those damn plastic shark fittings on one of the big airlines and it leaks tremendously, the tanks bleed out in a matter of minutes.