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truk4u
09-19-2006, 09:02 PM
Just a little FYI regarding the level low. A few times I have parked the bus and within two days the front end has dropped it's nose. There are no leaks that I can find in any of the valves or front bags. No leans, just low in the front end.

The solution is to once again cycle through the various positions with the level low switch and then go back to the drive position and leave it there about 1 minute before shutting off the engine. Then it seems to hold for probably months with no problem.

It seems like the level low switch is very touchy and if you turn it quick from any of the adjustment positions to drive and shut off the bus, it kinda of acts like the valves don't catch up quick enough to hold when you kill the power.

I don't have an aux compressor, so I hook shop air to the aux tank valve, turn on the key and then play around with the switch positions without having to run the engine. It's amazing how much air is sucked out of the aux tank when trying to raise the rear sides or front. This also helps when looking for air leaks since there is no engine noise.

Now if there was just a way to not get a bath in soapy water while looking for valve leaks.:rolleyes:

Orren Zook
09-20-2006, 05:06 AM
We have an ultrasonic leak detector in our service department that emits a digital sound through earphone/headset when leaks are detected. A shop that works on bulk (blow down) tankers should have one these in your area... any cement or limestone fleets nearby?

Jon Wehrenberg
09-20-2006, 07:03 AM
I have seen an ultrasonic leak detector in use and it is an excellent way to pinpoint leaks, but there is a poor man's leak detector and that is a $5.00 stethoscope.

A while back I had a leak somewhere in the engine bay and my ears told me it was on the RH side, forward of the big alternator near the starter. My stethoscope, with a small funnel on the end located it on the small bellows that tensions the fan belt, and it located the leak in seconds.

lewpopp
09-20-2006, 09:59 PM
Relentless.. Thanks, I got the bolt today. I think you sent it to me. What kind of business are you in?

I rebuilt the Microphor toilet piston because it was giving me troubles. I would have to flush it twice to shut it off. I was afraid a stranger would flush it and leave it running. Now it's fixed and go to go again.

I had a few problems because I didn't have an owners manual. The instructions that came with the rebuild kit was dofficult to digest. I'm sure the book would have broken it down better.

Jerry Winchester
09-21-2006, 11:12 AM
Lew,

Not that it would help you on your cell phone dial up system, but I think the manuals and stuff for your toilet are posted on the information part of the POG website. Or at least I sent them to Jim Skiff some time back.

If you have a manual issue, don't forget to look at the site for pdf manuals and such. Also, I have most of these manuals downloaded on a USB drive that I keep in the coach. Very handy when you are in BFE without any internet service.

http://www.iomega.com/media/direct/images/products/image_xlarge/xlarge_33027_2_dd49.jpg

lewpopp
09-21-2006, 09:31 PM
Thanks Jer,

What were those things pictured below message? I noticed some plug ins and what the frig was the chain and clasp? Was that bounty you got from the last firgate you stormed? Arrrrrggghhhhh

It would be nice to get a CD for all of the manuals.

I guess I'll just fade into the sunset and hope for the best and hope some pirate doesn't raid me. He'll get really angry when there is nothing to pilage.

Jon Wehrenberg
09-21-2006, 09:40 PM
Winchester,

I see the chains....where are the whips?

rfoster
09-24-2006, 09:35 PM
Truk4u: I read with great interest your comment about the level low - and hooking up to your shop compressor. I hooked up to mine and at 110 psi, wouldn't lift up- How much PSI at your place? Or maybe I just couldn't get enough volume. It seems there is a restriction in flow going in, but flows out quicker than I want it to. Must be the added weight of the generator baffle - I just realized how much they weigh from Mango's photo

truk4u
09-25-2006, 08:53 AM
Roger Dodger,
Mine will go to 120, but 110 sould be enough to get you to ride height. The front end comes up a little, but the only way to really get it to raise is to dump the tag axle. Mine also has an air filler valve stem in the steering bay, looks like a tire valve, that will also pump up the aux tank. When I use either fill method, it seems to go in as fast as it comes out.

186
Valve stem air is just below and a little right of the aux gauge

Jon, I'm stumped!:mad: Now the front end is down overnight. No leaks at any of the valves in the steering compartment and nothing at the valves under the front end. If I cycle the level low valve to one of the three positions and then turn the valve back to drive, when I turn off the key, there is a quick small blast of air from somewhere under the bus. This blast of air must be coming from a valve and maybe it's not sealing off, but I can't hear anything leaking. Looking for help from the master to narrow down my search!;) POG is near, gotta hurry...

MangoMike
09-25-2006, 11:20 AM
Tom,

As the weather gets colder we're going to find that those small leaks will no longer "heat" seal. It will be an eye opener in SF w/ 30* mornings.

Get out the soapy water.

Mike

Jon Wehrenberg
09-25-2006, 03:06 PM
Tom,

Mango is on target on his comments about cold. But to get to the heart of your problem requires a methodical tracing of the system and soapy water or a listening device.

There is absolutely no way anyone can diagnose this type of problem because there are so many potential failure points. As a short example I had the leans on the LH rear two days in a row. I exercised the valves and shut it off using the normal procedure and on two successive days the LH rear was down.

On the third day I raised the entire coach (not just the rear) because I had some work to do under it and it sat fully raised for a couple of weeks. When I went to lower it all the way down, the LH rear wouldn't move. After screwing with the switch and hearing air several times, the rear left finally went down as I had commanded despite the fact I did nothing more than cycle the switch about 10 times. My point is it could be a leak, a valve not "switching", a failed solenoid in the valve pack, or even a leak in the ride height valve.

On this forum there are a whole bunch of us guys who are about to get up close and personal with our level low systems. You, Mango, Roger, Jeff, Trims30, Reelentless, and me all have coaches that are bumping up against 10 years old, which is exactly how old my old coach was when I bit the bullet and went through the whole system. I think Ed Roelle has already been playing with his level low system.

Kevin Erion
09-25-2006, 03:41 PM
I also have a "LEAN" problem that has arrived in the last few months, I am waiting untill after POG2. I hope to be a lot smarter due to Jon teaching us how to rebuild the famous Norgen valves. 99 built in late 97, I guess 9 years is close to the 10 year window.
Kevin
99 Marathon XL45

Jeff Bayley
11-01-2006, 05:52 AM
Regarding air leaks, I recently went into Prevost to have them track down an air leak since my coach would fall within a few hours. 3 days and $4,000 later they had replaced this valve and that one and kept on replacing one item after another w/o solving the leak. I finally was boarding the coach while still in the shop and when I heard a hissing noise and said to the tech "What's that coming from under the steps here?". Turned out the air operated piston added by the converter to run the step cover was the culprit. This was tied into the coach's air system.

The tech's also explained to me that the archeitecture of the way the valves work on the newer set ups is different than my bus (97 title but 95 chassis). Don't know what year they changed it but the way the new method works prevents the coach from falling with a check valve method or something of that nature. I can't quote you chapter and verse but you could find out by asking Prevost. They have a way to update the old system to the new system and they changed an adequate number of parts on mine to nearly complete the revision but not all the way.

Related, I just took care of an air leak on the air flush toilet. I rebuilt my Microphor toilet about a year ago (what a pain) but this air leak was coming from air leaking back out of the worn out rings on the electronic two cyclinder air pump for the toilet in the bay. I installed a check valve to keep the air from leaking out backward through the supply line and it holds air 100% now. I was turning the air pump off every time after using the head but I learned the hard way that if you turn that pump off before it is done cycling after the flush then some valve (that lets the water in) doesn't shut off completley and it overflows. Trying to train guests how to shut this off properly was a real pain.

Jon Wehrenberg
11-01-2006, 07:16 AM
Jeff,

You may consider yourself a newbee, but you have now gotten a very expensive education thanks to Prevost. You are now a seasoned old timer, and anytime you hear or suspect anyone intends to take their coach to Prevost or any repair shop to cure the leans make sure you repeat your story.

For $4000 I could have replaced every aux system component and had money left over to have taken the bling award away from King Roger.

BrianE
11-01-2006, 12:15 PM
The solution is to once again cycle through the various positions with the level low switch and then go back to the drive position and leave it there about 1 minute before shutting off the engine. Then it seems to hold for probably months with no problem.

Tom, As soon as the temp dropped as we got near the NW, we also started seeing air system problems. Suspect that you could drive yourself nuts trying to keep ahead of these transient misbehaviors. Am curious though, about switching back to the drive position for that long (1 minute) before shutting down. In my bus, that length of time will ruin my level job as it re-seeks the drive level. In our experience (limited) for some unexplained reason it does help to go back to the drive position and immediately shut down. :confused: Misery loves company!

BrianE
94Liberty XL

Jon Wehrenberg
11-01-2006, 03:12 PM
Brian,

The way you describe is how I do it. I pause in the road position for about one or two seconds and then shut the bus off. Any longer and it goes out of level.

The cold weather is just a way of forecasting level low problems. If you can get your system to function properly, leak free in the cold, it will generally work perfectly in warmer temperatures. When we lived in the western NY area we were always leaning one way or another until I just went and rebuilt the system.

truk4u
11-01-2006, 09:04 PM
Brian,
Sorry for the wrong number, I haven't a clue where I got a minute, I should have said a few seconds otherwise you lose the level. That's what I do and it seems to work out pretty good. Cold temps will sure bring out the air and coolant leaks.:(