I did the test you recommended twice. I can hear no leaks whatsoever. When the brakes are applied and when I'm looking under the coach I do see a small puff of air hit the dust below, but I believe that is normal. No leak noises. Air bags are full. Gauges reading good now.
Air is used to release the parking brake.Spring pressure will slam it in if air pressure drops to low. You normal brake is held out by spring pressure in the cans. When you push the peddal down it applies air to put your brakes on. If you loose air pressure first you will lose control of your foot brake then when air pressure drop lower you parking brake will try to engage. to sto you. I say try because when you get rolling it is going to have a had time stopping that rolling mass of weight. I don't know if you have seen those run-away traps of some of the mountain road, Do you know what they are for? If you can't find that air leak or why your air gauge pressure is going down.. Don;t go down the mountain. Leaks could be in air lines or diaphrams in the cans. Is the air leak only when you apply foot break?
How is your air pressure when Parking brake is released? Does the AP stay up or is it dropping? Thinking on one of the post you said you where walking around checking air leaks. Does this mean you parking break is engaged while you are walking around? If so the parking break would not be using air? You might have to release the PB find the air leak. Block you wheels good, than check again for air leaks.
Does the gauge go from normal to 0 and back to normal as quickly as if you turned a switch on or off, if so sounds like a sending unit or electrical problem with the gauge. If it takes a few seconds to drop while applying the brakes then I would look for an air leak. Do not take a can apart if you have a leak in one without proper tools as the spring in the can cause serious injury when it comes apart. The puff of air is the valve dumping the air out of the chamber when you release the brakes.
Do not take a can apart if you have a leak in one without proper tools as the spring in the can cause serious injury when it comes apart.
X3 do not mess with the cans. techs get killed working with those things. leave it up to the pros.. the springs that are in the emergency side have a lot of preasure on them so it WILL stop if there is no air.
2000 K3500 CCLB DRW 6.5 TURBO
2009 Cougar 320 SRX
2007 atlas 24 auto hauler
1987 GMC origional low miles
Like Moses, I came down the mountain ! After consulting with some mechanic friends, I made a judgement call that I did not have a brake issue, but an electric/elecronic issue. Early in the morning, I unhooked my Jeep from the coach and tested the brakes several times on the summit area where I could get up some speed and apply the brakes hard. No problems, so I headed down the mountain using the exaust brakes as I do anyway. This was near Challis, Idaho. From there all the way to Darby, Montana (over a very steep pass on the Idaho / Montana border), I had not the slightest sign of brake problems. However , near Darby, Montana, I started getting other warning lights coming on. In addition, the voltage gauge went suddenly from 12 to 9. I came to a NAPA auto parts store which had an area in back I was able to pull in to. (Here it gets interesting.) I stopped in the lot and tried to put the coach in neautral. IT WOULD NOT SHIFT. So, I circled around the back lot to put the coach in a position where a tow truck could hook up to it if necessary. I set the brake, chocked the wheels and shut down. I let it all cool down and tried to restart it. It would not start without a boost form the house batteries. (It then shifted to neautral) I asked the NAPA guys to test my batteries and the batteries were completely dead, shot, tested as low as their equipment would test. They tested them hooked up and unhooked. So, I bought two new batteries, and the coach started immediately. I then proceeded to my site just south of Missoula with no problems. The voltage registered around 13.5 to 14 on my gauge. Bottom line, I suspect the entire issue was battery related: very low batteries doing some strange things with my gauges and warning signals. So, I believe it's fixed for $214. I did have one outfit in Idaho (they called Newmar with no coach information from me, and having never even seen the coach), and with Newmar Service diagnosed the problem and came up with a fix estimate of $1600, parts and labor (no batteries). They concluded (sigtht unseen) that the problem was electronic and was in a control box (some cold solder issue). Anyway, I think the alarms were all false alarms; that I never really had a brake problem; that I had a battery problem instead. Thanks to all of you who provided input . It all helped in the decision makiing process. I really appreciate this site and you readers/contributors.
* This post was
edited 06/03/12 10:37am by USMC46 *