Spend a Saturday With Your Coach

            Just imagine it is a rainy Saturday, no golfing, and nothing to do. It’s a great opportunity to play with the bus. You can accomplish a lot even if you don’t have a 5 foot Snap-On tool box or mechanical skills. Crank up the radio, grab a cup of coffee and get ready to play with your coach without burning a gallon of fuel or getting real dirty. There are a lot of things that are always worth doing but we never seem to take the time. Start with getting the coach maintenance history in order. Get all the receipts, get copies of the shop work orders, and begin by sorting them chronologically. If you don’t have a log book now is a good time to create one. I actually have two log books which have two different purposes. My driver’s log book lists all my driving activities. I record the date and mileage when I get to my destination such as a rally or my return home. I also record all my fuel purchases which includes the gallons, cost per gallon, and location of the place where I fueled. My flying has gotten me into the habit of keeping a log book, and if kept over a long period of time it is an excellent tool. I use my log for remembering where we have been, what we have paid for fuel, how much fuel we have burned per mile (I use a one year average because individual trip data is inaccurate) and it is a record for tax purposes if you do use your coach for any business activity.

The maintenance log is the book in which I track when I do oil changes and all other routine maintenance tasks. But I also created a form with all the scheduled maintenance items listed (along with part numbers for filters, belts, air bags, etc.) so I can not only list them as completed, but forecast when events are due. My form lists when I have to do such things as replace differential fluid, coolant, brake chambers, air bags, tires etc. My maintenance form is for my coach exclusively. Each coach may be equipped differently even from the same converter so make yours specific to your coach in a format that works for you. Look in the articles section of this web site for my maintenance form.

Every maintenance event or repair is then recorded along with as much information as possible so I can remember the part numbers, what work was involved, and from that I am able to predict replacement dates rather than experience repairs after a failure. Along with my records I also retain all the associated paperwork such as installation instructions, copies of invoices and packing slips. I not only know where I bought the components or devices, I also have the information relating to installation. My log books are not only good memory aids, but when I decide to sell the coach I can advertise it has been well maintained and I can prove it with the detailed records. I will pay extra for a coach (or car or plane) that has a provable service history.

With the paperwork out of the way just kind of poke around doing things that we should all be doing but always seem to find other things more important. A good place to start is at the engine area. Check the fluid levels. We probably always check them, but this is a good time to even check the power steering fluid level, the cold coolant level, and the oil level in the engine and the oil reservoir. While back there take a look at the belts. Make sure they are not frayed, don’t have signs of teeth missing, and generally show no signs of cracking or splitting. If needed replace any that look questionable and keep the old one as an emergency spare. Get a flashlight and look under the engine and transmission for wet spots, and look at the engine and transmission for any signs of leaking of any fluids. The engine doesn’t have to be polished, but it does need to be free of any signs of leakage.

Look at the batteries. Not just chassis, but the house also. Are the terminals clean and free of corrosion? If not, this is a good task. How old are the batteries? If they are lead acid are the cells up to the proper level? Now would be a good time to write a date when they should be replaced on a piece of masking tape which is stuck on the batteries. You can wait until your batteries fail, but when they start to fail you may experience some weird electrical issues and life starts to get complicated. This usually happens when you are far from home. I use 5 years as the replacement interval.

When is the last time you used a tire pressure gauge on your tires? Even if you have a tire pressure sensing system this is a good opportunity to check each tire using a gauge (that has been checked against a master gauge at a tire shop) so you can compare the pressure reading against what the sensor system shows. While you are at the tires look at the date codes, and if they are 6 years or more old, give the tire a very close examination. Look for sidewall cracking or any evidence of aging. Also run your hands across the tread. Long before you can see signs of unusual wear patterns you can feel them. It is nice knowing your tires are in good shape, within six years of age and are wearing true.

Before you leave the tires verify your hub seals are not leaking. Our wheels all run on a pair of bearings and those bearings have a life of only a few miles if they are not properly lubricated. That means the steer and tag axle hubs need to have the oil level up to but not over the oil level mark on the clear plastic cap on the hub, typically out of sight behind a hub cap. Pull the hub caps and verify the fluid level. Then because the tag and steer tires are not likely to show leaks until they get bad, stick a finger through one of the holes in the wheel and rub the finger in the dirt and grit on the back side of the rim. If the finger shows a dry dust you have no hub seal leak. The drive axle wheel bearings are lubricated by the differential oil. Unless you have a pit or good stands to support the coach you should not attempt to check the differential fluid level. You also are unlikely to see evidence of a hub seal leak on the exposed portion of the outer drive axle wheels. But you may see signs of greasy dirt or grime if you shine a flashlight between the two drive axle wheels. A leak is going to show up on the most inner part of the inner drive wheel, but you are likely to see evidence of grease between the two wheels, and maybe even on the tires themselves.

If you find evidence of leaking on any axle don’t delay a repair. You not only risk losing a wheel bearing, or worse having the bearings seize, you also get grease or oil on the brake shoes or pads which compromises your stopping distances.

Next check the lights. A lot of our coach lighting is dual bulb. Often a light will work, but only one of the two bulbs is working. This is a good opportunity to get every single light and all bulbs working. We also seem to overlook our aging wiper blades. Now is a good time to pull off the rubber wiper and replace with a new one. It is always nice to not have streaks across the windshield in the rain. While working around the coach check and fill the windshield washer fluid.

When was the last time you have looked into the belly of the beast? Look at the generator and make sure it has full fluid levels and has not been leaking or dripping. Open up the plumbing bays and look behind the fascia panels. Look at the guts and make sure there is no leaking of water or coolant (almost always used to heat the water heater or to keep the bay warm in cold weather). Do you have water filters or a water conditioner? This is a good opportunity to service those. Don’t forget to record the date of service. I have been in the habit of adding a small amount of chlorine to the holding tank every six months or so. On my most recent water system service I added about a cup of Chlorox. If you find the odor objectionable run treated water through all the sinks, the toilet, the shower and even the washer(s). Let it sit for an hour or two, drain the water holding tank, the HW tank, and refill with fresh water. Then flush all the water lines and items that have had the Chlorox pass through them.

If you have any heat or AC system filters in the bay(s) replace them or clean them. Record the date of cleaning. If you have Cruise Airs or any other type condensing units in the bays try to access the condensing coils and clean them. Even if it is impossible to completely clean the coils any cleaning is going to be an improvement in efficiency.

Finally, take an inventory of what you have in the bays. Weight is bad, space is good so if you have been carrying extra stuff you never use, pull it out of the coach. Why drag it around if you never use it. But there are things that are good to carry even if you never use them. Spare parts are sometimes worth their weight in gold. This is a good time to make sure you have spare bulbs, relays, switches, fuses and circuit breakers, belts, fuel filters, and maybe even some cabinet hardware such as latches or hinges. Even if you are not a mechanic it is also good to make sure you have a good selection of hand tools for the simple repairs we all seem to have to make occasionally. I also carry extra fluids such as coolant and transmission fluid.

By now you probably have not only done what has been listed above, it is probable you have found other things on your coach you have been wanting to do, or found needing some attention. The devil is in the details so I use opportunities such as a free day to lube the bay door locks, make sure the bay lights are working, and generally make sure everything is up to snuff. Now start the engine and get the air pressure up. While it is building air pressure chock the wheels so the coach cannot roll. With the air pressure built up, shut off the engine and begin a DOT brake check. First release the emergency brake. You should see a small drop in air pressure and then no change. The DOT test allows the loss of air pressure after the emergency brake is released over and above the initial drop as the brakes are released. That allowable loss is slight, such as one or two PSI per minute. As far as I am concerned there should be no loss of pressure. If you are willing to tolerate a slight pressure drop consider this: are you losing pressure because a brake chamber diaphragm or air hose is failing, or is it just a leaky fitting. A leaky fitting might be OK, but a leak in a hose or diaphragm could be the first sign one of them is about to fail. Do you want to take a chance?

After the emergency brake has been released and the pressure drops determined, next apply the service brakes. Step down hard on the brake treadle and hold the pedal, observe the initial pressure drop, and confirm there is no further pressure drop. Again the DOT allows a slight ongoing drop in pressure, but in my opinion there should be none. After confirming the leak free service brake operation, turn the key on to verify brake system pressure alarms. Fan the service brakes to bleed air pressure. At 60 to 70 PSI you should observe the brake system warning light and operation of the audible brake system alarm or buzzer.

Continue fanning the brakes and at approximately 45 PSI the emergency brake knob should pop up and the emergency brakes should automatically re-apply. This procedure should be followed prior to every day of driving. Not many of us do it, so it is not a bad thing to do when you have an opportunity. At the very least, when getting ready to roll on a trip watch your pressure gauges as you release the emergency brake for dropping pressure, and then apply and hold the service brakes  and look for pressure drops. You haven’t verified alarm operation or emergency brake automatic operation, but at least you know your brake system is leak free.

A job everyone avoids is changing air conditioning filters but it needs to be done. Some converters make it easy to find and access the filters, others less so. Bottom line however is for efficient AC operations the filters need to be clean and kept clean. While working with the air conditioners it is a great time to check and record the temperature difference between return air and supply air. Why do you care? At some point air conditioners need service. Service can be cleaning the evaporator or condensing coils, or it can be recharging a system that has lost its refrigerant. An easy way for me to check temps is to aim my infrared temperature gun at the return air and the supply air. Then I record the numbers (take the temps after the units have been running for a while, but not when it is cycling off and on) and retain them. I can then periodically check the temps again and compare the recent readings with previous readings. The greater the temperature spread between return and supply air the better and more efficient the units are working.

There is nothing worse than finding out on a sunny 100 degree day that one of your 3 air conditioners has failed so keeping accurate temperature readings over time will show if your air conditioners are continuing to work well or if they need attention. A good temperature spread is likely to be in the 15 degree to 20 degree range. This holds true regardless of if the system is a Cruise Air, a roof air or even an over the road full bus air system.

There is rarely a trip when I don’t find something to fix, adjust or replace. An inspection inside the coach will reveal if you have any loose hinges, drawers out of adjustment or any light bulbs not working. All are easy things to take care of. I usually go further and open all the cabinets and drawers to see what is in them. Then I get a big garbage bag and throw out all the extra stuff we have gathered since the last time I cleaned out the drawers, cupboards, or closets.  Don’t ask me why we always tend to save the map we get of every campground we stay in.

By now you should feel pretty good about the coach and what you have accomplished by giving the coach a little attention. You will have more confidence in it, you verified it was in good shape and all you need now is an excuse to go on another trip.

Jon W. Wehrenberg

12/23/2011