| Author |
Message |
Sean Mormelo (Sventvkg) (66.58.223.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 19, 2004 - 10:09 pm: | |
WE replaced the Truttle valve on my bus today and now there was no leak..The bus would air all the way up to 120psi If we reved it and the back would air up no prob..but the front axle will not....There is a slow leak somewhere that will not allow it to come up..Any Idea what it could be? Bus has been sitting for 2 years..Is there some sort of a manual valve near the front bags that could have frozen open a bit? We do not think it's the bags as they are new... |
Derek (Derek_L) (24.83.196.239)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 19, 2004 - 10:14 pm: | |
A leak that doesn't allow the suspension to come up is far from a slow leak. I would use shop air if possible to keep air pumping into the suspension, and start listening for leaks (WHILE THE COACH IS PROPERLY BLOCKED, MIND.). If it's that big that the front won't air up, it's bound to be a big leak. |
Jim Stacy (209.247.222.99)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 19, 2004 - 10:32 pm: | |
Sounds more like a front leveling valve with issues (disconnected link, no air available, etc).
Derek is correct that it would take a BIG leak to cause your problem.
Jim Stacy |
Jayjay (152.163.100.73)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 19, 2004 - 10:43 pm: | |
At 120 PSI try the air horns or wipers, if they don't work, then the pressure regulator near the front air tanks is out of adjustment. Screw the knob CW to increase the pressure. Try disconnecting the "out" fitting from the regulator to see if the line or regulator is clogged or not.
If the above helps, remember to not screw the regulator knob all the way in, 'cuz 120 psi may be enough to "pop" your air bags. Most of them are at normal ride height at around 100 PSI. Cheers...JJ |
Sean Mormelo (Sventvkg) (66.58.223.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 19, 2004 - 11:45 pm: | |
everything works..Air horns, wipers, doors, etc etc..the only thing, is the front suspension will not air up..We are hearing no leak in the air system to speak of...I'm thinking some valve must just be open..Need to jack and block up the bus in the next couple days to see what it is....Thanks. |
Derek (Derek_L) (24.83.196.239)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 12:01 am: | |
Or it might be a valve stuck closed? Front levelling valve perhaps, as Jim Stacy said. For some reason your front bags are not getting air, or losing it fast (but you said no leaks?), work your way backwards, I'd say. |
Richard Jones (63.80.251.75)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 2:46 am: | |
If your bus has a "Kneeling Mode", you may have a broken or loose wire to the solenoid valve. This will not allow air to the front bags.
Richard |
Sean Mormelo (Sventvkg) (66.58.223.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 3:56 am: | |
I think it does have a kneeling mode..It's an MC5C...Anyway, I don't know where this solenoid valve might be...looks like I need a service manual.. |
TWO DOGS (63.185.73.171)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 7:56 am: | |
if the front aired up before you installed the treddle valve....that is where your problem is...in the instalation of the treddle valve |
loren bailor (208.24.179.27)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 2:34 pm: | |
When I bought my Prevost the front would not air up and it had no leaks. I found " after I drove it home a hundred and eighty pounding miles later"
that the little rubber end on the shaft that works the valve to increase and decrease pressure
to the bags was broken and needed replaced. If I had known this I would be taller today.
Loren |
Derek (Derek_L) (24.83.196.239)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 2:39 pm: | |
No critisism intended, just curious... How was the drive back? I once rode on a MCI 102DL3 that was kneeling and the driver drove for about 3 blocks... About 15MPH max... By the time we figured out what happened, whilst driving, the bus was probably bounching off the front tires. |
Sean Mormelo (Sventvkg) (66.58.223.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 5:01 pm: | |
Two Dogs, The Treddle Valve was leaking so we thought that was the problem sowe replaced it. Afterward, the bus aired up as far as PSI..The back, the wipers, horn etc and I could put it in drive...Just the front axles will not air up.. |
TWO DOGS (65.177.144.174)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 5:10 pm: | |
sure sounds like the sensor that tells the bus how high it is...should be an arm on a valve... |
Sean Mormelo (Sventvkg) (66.58.223.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 20, 2004 - 10:23 pm: | |
Thanks man..We are blocking it up tomorrow and getting under there to see what it is. Hopefully we'll have it solved! |
Glenn (166.102.79.94)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 6:46 am: | |
Sean,
After our 4104 sits for a while the front goes down. So far I've just taken a jack and put it under the front bumper and lift the body a little.
This will work the leveling valve enough to get her started up.
Glenn |
Jim-Bob (12.46.52.74)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 1:37 pm: | |
The front of my 4104 goes down too, after the air pressure goes to "0". Evey time somebody goes in or out, the suspension valve tries to adjust for the weight difference. Once you run out of air, it just goes right down.
And jacking up the body is going the wrong way. When you raise the bus, the valves bleed out air from the air bags trying to bring the bus back down where it belongs. Try that when the air is up & the bus is shut down. When you raise it, air bleeds out immediately. You need a small 110 volt compressor to keep the bus air up & all corners should stay up then. |
Glenn (146.126.61.241)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 2:58 pm: | |
Oh well, it works for me.
Glenn |
t gojenola (66.58.192.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 4:55 pm: | |
I have found that on my 4106 the leveling valves need to be exercised. Sometimes, but not always, after sitting a few months, one or more of them will not do its job when aired up. A trip or two round the block, and it will work fine. This phenomenon may explain Glenn's results accomplished with the jack.
tg |
Tom Caffrey (Pvcces) (65.74.66.104)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, September 21, 2004 - 11:57 pm: | |
Jim-Bob, I don't know if you're aware of it but there is a check valve in each leveling valve. It's job is to prevent exactly what you're seeing, so it may be bad.
These check valves are designed to be replaceable without removing the leveling valve. They are right at the air inlet on the valve, so replacement only involves disconnecting the supply line and unscrewing the valve and screwing in a new one.
If the front of your coach goes down even with a good valve, it means that there is a leak somewhere after the check valve. In that case, it's time for the soapy water spray to find the leak.
Leaky air bags will often show up with the appearance of a foam on the outside of the bags, sometimes over a large area.
Good luck finding the leak.
Tom Caffrey PD4106-2576
Suncatcher |