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DTV Converter Question We hope you can clarify the DTV converter box issue with our motorhome. Do we need to purchase a converter box for our motorhome TV, or will the place we camp at have the right digital connection for us? Please clarify this dilemma.
Richard Johnson
Via e-mail That depends on whether the campground you stay at provides cable or satellite hookups that you can plug into. If these are not available, and you want to watch over-the-air TV, then you’ll need a converter for each TV that is not a digital model. If you use your motorhome's rooftop terrestrial antenna, you’ll need the converter(s).
Bad Brakes I have a 34-foot 1998 Newmar Dutch Star motorhome on a 1997 Ford chassis and have been having brake trouble for quite a while. The brakes just don’t seem to want to stop the coach. I replaced the brake pads awhile back, which didn’t help a bit. I've replaced all of the brake fluid, and I thought that helped. I also replaced those pins, or whatever you call them, that fasten the calipers to the frame. A month ago when backing into a parking spot on a little bit of a grade, the coach didn’t seem to have enough power. My hubcaps were very hot on all four wheels. Three days later when it was time to go home, the brakes seemed okay. I drove the coach home and the brakes didn’t get hot. I decided that I apparently overheated the brakes and that I would change all the calipers and brake pads again. I also took the front rotors off to have them turned. They were not really bad, but while I had everything apart, I did it. I left all the brake lines hanging while I was having the work done, and I also had some other things to do. I wasn’t worried about the brake fluid draining out, as I was going to replace all of it again. Well, I gravity-bled all the wheels and replaced the fluid, and when done the brakes didn’t seem right, so a friend and I pumped the brakes up with the pedal and bled them again. This seemed to help, but when the vehicle sat for two days, I went back to check the pedal and it basically went to the floor. I could pump it numerous times, and eventually the pedal would firm up again. I then read on the Internet where I must have gotten air in the ABS and would need a tool or scanner to bleed them. So I took the coach to a local garage, and they bled them for me. The brakes seemed better and I drove the vehicle to another campout. The brakes really didn’t feel spongy, but the pedal was soft. Also, when it sat for two days, the pedal would go down, and I would have to pump it numerous times to build the pressure again. I took it back to the shop and had the system bled again, and now I have a very hard pedal when the brakes are up, and I feel confident that they will stop the coach. But once again, when it sits a couple days, the pedal will go way down and numerous pumps are required to get the full pedal. My question is, what can be causing this problem? I ran three quarts of fluid through it — I am not sure how much the garage had run through it — but it sure seems like all the air should be gone. Am I having master cylinder trouble, where one side is not holding fluid like it should be and will finally pump up? I am at a loss. Paul L. May, F243341
Kemp, Texas When discussing hydraulic brakes in motorized vehicles, the following criteria apply: - Always use the D.O.T.-approved hydraulic brake fluid for the specific vehicle as stated by its manufacturer.
- Always ensure that the brake fluid bleeder valve (the hollow bolt) is located at the uppermost portion of the respective brake shoe wheel cylinder or disc brake caliper. I always take the bleeder screw out beforehand to verify there is no restriction to the brake fluid flow.
- Successfully bleeding all of the air out of a hydraulic fluid brake system is rarely achieved via the old-fashioned two-person way — pump up and open the bleeder valve. Here’s what really works: a small but constant amount of air pressure (30 psi from a tire on the vehicle you’re working on) is applied to the diaphragm (the internal part of a brake bleeder ball — a special tool is needed) and provides a steady and controllable flow of brake fluid from the master cylinder to each wheel cylinder. The next part is very important: at connect a short bleeder hose to the top of the bleeder screw (fitting), and submerge the lower end of the hose (or tube) in brake fluid in a small, suitable container.
This allows you to see the last bubble of air exit that portion of the hydraulic fluid brake system.
- Of super importance: most vehicles that I know of with ABS brakes also include a powertrain control module (PCM). Therefore, a control program for the ABS brake system exists within the vehicle’s PCM. Consequently, the ABS device must be commanded (electrically locked) open by the dedicated scan tool (for that vehicle line) during the entire brake fluid bleeding procedure. Obviously, the choice of a qualified service provider is critical. Research your service provider carefully to ensure they have adequate equipment and experience to work on your brake system.
| The "Tech Talk" column is coordinated by Jim Brightly, F358406. In addition, Bill Hendrix, F761S, and Ray Hobbs, F10175, serve as technical correspondents for the column. Questions may be addressed to "Tech Talk," FMCA National Office, 8291 Clough Pike, Cincinnati, OH 45244. We cannot accept phone calls. Questions may also be sent via e-mail to techtalk@fmca.com. Please include your name and address with your query. Because of the volume of letters received, it isn't always possible to draft individual responses, but representative samples will be published in the magazine. Letters that are chosen for publication in this column may be edited for space and clarity, and they also will appear on FMCA's Web site: www.fmca.com. |
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