| Author | Message | ||
| bobm (198.81.17.187) Rating: N/A |
one of my front air tanks has a pin hole leak. big enough to keep from building up pressure past 30lbs. bus is a 1980 crown atomic the tanks are tough to get at but i can put my finger on the hole. any suggestions for a quick fix so i can get the bus home | ||
| Don Peter (172.140.47.246)
Rating: N/A |
Drill the hole out a little and use a sheet metal screw with rubber faucet washer under it. Clean the area around the hole well first and sand lightly. -- Don | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Sorry Don, I have to disagree strongly here. I sure wouldn't trust a sheetmetal screw for that task! They aren't very good metal and not much thread there either, especially for a job that your life will depend on!! At least, I'd drill the hole out to 10/24 size, tap it and screw in a #10 machine screw with some loctite "permanent" sealer on the threads to permanently lock and seal it in place. A larger screw would be in order if the metal isn't "clean" with that size hole....remember, a rusted out pinhole is like an iceberg...the tiny hole is just the first part to rust all the way thru, of a very large area of internal rust. THAT SAID, I'd strongly recommend that you get a new tank, period. If it's rusty enough to have a pinhole it's probably bad all over inside. I certainly wouldn't want to find out the hard way as my tank blows while I'm cruzing my 22,000 pound vehicle at 70 MPH!!! Be safe Gary | ||
| bobm (198.81.16.29) Rating: N/A |
thanks. I plan on replacing the tanks but need to get it home so i can work on it | ||
| Peter Broadribb (Madbrit) (216.67.217.15)
Rating: N/A |
If you can get to it, try placing a piece of sheet metal with some sealer over the hole and secure it with a couple of loooooong hose clamps, or join a few together. Try to get one to be directly over the hole when you tighten it down. That should be good enough to get you home. Madbrit. | ||
| OAE Palmer (208.164.96.121) Rating: N/A |
And the winner is...... MADBRIT..!! Here is one as good...GO BUY a portable air tank and 3 fittings and either use the tank in place of the bad one OR...mount it inside the coach and plumb it thru the bulkhead using steel or copper tubing....in the end you get to keep the tank for "spare air anywhere". You'll spend a couple of $20's and be on the road safe, and so will those on the road around you. | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
I SECOND OAE's idea ! It doesnt matter if the bus is "just getting home" or out on a 3000 mile trip...safety is safety and a bad air tank is just as dangerous 500 feet from your house as it is on a freeway! Gary | ||
| degojoe (198.81.17.38) Rating: N/A |
Gary, what exactly is the danger. if the air leaks out faster than the compressor can supply it, the brakes will apply and the bus will stop. an observant operator will notice the dropping air pressure and pull over. if a patch holds for the initial build up of pressure and then fails, the risk is being stranded on the roadway. | ||
| Don Peter (172.175.169.242)
Rating: N/A |
I was wondering about the danger, too. We blew an air line under the dash of our 4104 when we were about 100 miles from home. I heard the hissing and saw the pressure dropping so I got off the road. I was able to feel where the leak was with out removing any of the dash so I got some black elect tape and taped it by feel. It still leaked a little, but the compressor could keep up. We drove home and I replaced the bad hose the next day. -- Don | ||
| Steven Gibbs (12.148.43.7)
Rating: N/A |
The danger isn't in the failure of the repair causing a small leak. It is in the further weakening of the tank while trying to make the repair. Compressed air packs quite an explosive potential due to the fact that it keeps expanding (exploding) for so long. What would happen if the tank pieces take out a tire or hits another vehicle? If the tank is not building beyond 30 psi it must be quite a leak. Even using the patch and clamp method poses a danger to you. How do you know that this tank will hold 120-130 psi? It apparently hasn't been called upon to do so since the leak developed. There you are checking to see if your repair is holding -- then BANG. Is this the parking brake tank? If so, if it fails your drive axle locks up right now and you will be leaving a set of those "mystery" quad skid marks leading to the shoulder of the road. | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Steven pretty much said it. The dangers are two: (1) almost instant application of the brakes if the side of the tank blows out (a hose breaking presents a much smaller "leak" that **might** allow you time to pull over. A tank blowing will have you stopping instantly. (2) the explosive force of the tank itself blowing shrapnel, etc all over the place. Bottom line here is that you're dealing with things that are safety related and there's NO fudging allowed. Fix it right or don't drive it, even if it's a two block trip!! There's a big reason that tank manufacturers go thru all the hassles and expense of periodically testing pressure vessels, and if one has even a tiny rust hole, no matter what application it's for, if it's for pressurized service it gets scrapped. At this point, I hope you get the point, and I further hope I don't read about you in the "accidents" section of the paper... fix it right... Cheers Gary | ||
| OAE Palmer (208.164.96.34) Rating: N/A |
There is another term for "mystery quad skid marks leading to the shoulder of the road".... we have called them suprise or sudden autograph sessions... 9 out of 10 times the evidence has been left on the road "due to pilot error" ...and FWIW, if the wrong tank blows suddenly from 90 POUNDS OF PRESSURE PER SQUARE INCH OF TANK SURFACE.... it can be way more exciting than a front tire failure, roundin a bend on a wet road with the rear axle locking up allows you to see where you have been and who is following you, of course a REALLY sharp driver can quickly use his back-up camera to see if there is anything interesting happening in the direction you are traveling.....! think about it! :D BTW...IF you want to test that tanks integrity around the leak hole, put a 1/2 inch socket extension on the pinhole and whack the other end with a 5-lb. Maul, if it breaks thru, you were dead meat waiting for the axe, if it doesn't think about how saving $40.00 will compare to seeing your coach on its side in a ditch and the meat wagon pulling away with your loved ones inside. DO NOT COUNT ON ANY FORWARNING. | ||
| Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A |
Man OAE, you make me chuckle!!! That's the best belly laugh I've ever gotten and you're DEAD on!! You oughta write a book on safety...everyone would read it and they'd probably actually learn!!! WELL SAID Gary | ||
| OAE Palmer (208.164.96.106) Rating: N/A |
(blush) awe...you're too kind....  I post on another mechanicaly related forum, where the atmosphere is every man for himself, it is a daily bloodbath of insults, character assasination, foul inuendos and verbal assualts. Coming over here is my relief valve, it gives me a chance to work on word usage that is not defensive or a double edged sword. I have been online and posting to forums since the spring of '95, and this place is without a doubt, one of the most comfortable , relaxed and informative sites I have come across. Ian deserves ALL the credit for his insight and efforts. This board is a precious jewel, in addition to Ian, the people who post here make it such and I hope everyone here appreciates the fact...! | ||
| OAE Palmer (208.164.96.41) Rating: N/A |
BobM.. Did you ever get your coach home us know what method you used and if you are any farther along now. | ||
| bobm (198.81.16.163) Rating: N/A |
i used a small self tapping screw with some JB weld.i didn't drive it very far to where i could work on it. the pressure held fine and now i've got the tank out | ||
| OAE Palmer (208.164.102.113) Rating: N/A |
Thank God you had a safe run. When I was a kid waiting for a paper route to open up, I took a job sweeping the garage area of a regional trucking company. The mechanics there would toss any air tank that was dented or showed any rusting, they would check the tanks integrity by ball peen hammering them in half a dozen places to check for internal rust or wall shrinkage, you could hear them rattle full of rusty flakes sometimes. I am lucky and haven't had the thrill of a full lock-up at speed, my Dad was an OTR driver and had many a line break emergency to deal with, I frankly think that learning how to deal with problems like a lock up are best not discovered or refined on the public roadway, in the presence of non-paying spectators, or Rubes who have no appreciation of a 29,000lb. 4 wheel drift while doing an impression of a Deer in the headlights. Thanks for letting us know how it went, I was really concerned for your success. | ||
| bobm (198.81.17.152) Rating: N/A |
good or bad thing about a 4104 is that it doesn't have the braking capacity to lock up the wheels. the only way the wheels will skid is on oil, wet, ice or sand | ||
| FAST FRED (65.56.24.241) Rating: N/A |
The 04 was designed to be gentle on stops , and for that reason the treddle valve does NOT allow full line pressure to the brakes. Seems this was done on many style coaches. IF you just want to lock the wheels go get a replacement treddle that DOES allow full pressure to the breaks. To check what you have install a gage at the wheel and stomp on the treddle. FAST FRED | ||
| Richard Bowyer (Drivingmisslazy) (66.190.119.82)
Rating: N/A |
I really do not think that an application of emergency brakes (spring brakes) will throw a coach into a skid unless you are on wet or icy roads. The brakes are only on the drive wheels and this is simply mechanically applied brakes. Anyone have an actual experience of this happening and what the results were? Richard | ||
| Buswarrior (Buswarrior) (64.229.210.131)
Rating: N/A |
You can do it yourself at slower speeds and take all of the mystery out of it. Go down the parking lot bravely at 20 mph or so (make sure you aren't being followed!) and put on the parking brake. Whoopee! It stops like a moderately firm brake application. (or, it should....)Spring brakes will bite a bit sharper, DD3's will rub a bit softer. Rather boring after you've done it once or twice. Of course, fasten down the spouse and the coffee maker, but then you do that before you go for any drive, don't you? As noted, you are only getting the spring applying the rear brakes. The spring is not as powerful as the air pressure that you can put to the same axle with the brake pedal. Simple extrapolation will let you figure out how it will feel at higher speeds, or, what the heck, find an open road... If you can't tell the difference between a joke and good advice, please ignore the "find an open road" reference, and sell your coach immediately. Encourage safer experiential learning where you can find it! happy coaching! buswarrior | ||
| OAE Palmer (208.164.96.94) Rating: N/A |
In all these replies no one addressed this problem.. (it came to me before I fell asleep) ..a sudden loss of air pressure would cause my engine to shut down, I would lose steering, electrics and then the brakes would suddenly not respond as expected. All of these things happening on the curves going thru OK City on I-40 at rush hour is a nightmare I would pay to avoid. | ||
| RJ Long (24.127.8.58) Rating: N/A |
Not quite, OAE, not quite: A sudden loss of air pressure in the system will only cause your emergency brakes to be applied. The engine will keep right on running - remember, you have to have about 30 - 40 psi minimum of pressure to activate the fuel shut off cylinder, which won't take place until you hit the master/ignition switch. If the sudden air loss happens, there should be enough air in the emergency tank (unless that's the one w/ the screw in it!) to hold the button down long enough to get your coach off to the side of the road, but then that's it, it's tow time. HTH, RJ PD4106-2784 Fresno CA |