This thread is a carryover from the Septembers Barthowners GTG in Tenn.
You can follow that thread over here.

quote:

Originally posted by Mary Ray:
Which is least mountainous. Memphis to Nashvile to Chattanooga or Memphis to Decatur to Chattanooga. Time is not a factor, I travel about 55 miles per hour and enjoy the scenery, in other words I am the tortois not the hare.

At this point Mary Ray's request for help extended to a PM in which she asked me to help teach her to bleed the brakes and change the brake fluid.

I've decided that this deserves it's own thread with other people pointing things out too.

Moved Reply:

quote:

Originally posted by Mary Ray:
Which is least mountainous. Memphis to Nashvile to Chattanooga or Memphis to Decatur to Chattanooga. Time is not a factor, I travel about 55 miles per hour and enjoy the scenery, in other words I am the tortois not the hare.

The route via Nashville then I-40 to Harriman, then US 27 to Chattanooga has lesser grades. Eastbound I-24 west of Monteagle has about 5 miles of 5-6% climb, then east of Monteagle, there's a 5 mile 6% downgrade.

Since you have drum brakes (at least in the rear), avoiding brake fade on an extended downgrade is important. The trick is to brake sharply, drag the speed down, then let it build up, then brake sharply again. This avoids overheating/glazing the brakes.

Obviously, the brakes should be checked beforehand.

Moved Reply:

Rusty, She will be going to the shop to help her run as well as she can, and I will ask them to make her stop also lol We just redid the front brakes (disk) and took her to the shop to make sure all was well and she has only been about 600 miles since then, by the way she passed her inspection of brakes. I know about braking hard and then coasting, do I need to know anything about downshifting etc? Don't have tachometer.

Moved Reply:

I assume you have a Turbo-Hydramatic 400. Without a tach, downshifting is discouraged. You'll get only a minimum of engine braking, but your Barth isn't overly heavy to depend on wheel brakes.

Moved Reply:

Rusty, again I thank you for your expertise.

Moved Reply:

quote:

Originally posted by Rusty:
Without a tach, downshifting is discouraged. You'll get only a minimum of engine braking, but your Barth isn't overly heavy to depend on wheel brakes.

I would never go down some of the stuff we go down without downshifting. Montezuma, Kennedy Meadows, Kern River, to name a few. It can be done quite well without a tach if you are properly informed beforehand.

My tire size and ratio is not the same, but perhaps someone here with the same ratio and tire size as your coach could post some advice on the appropriate speed range for downshifting into what gear. This information can be scientifically acquired by use of a tach or seat of the pants or intuitively acquired by an experienced 454 driver to be shared.

My trans is modified, but most stock TH400s cannot be hurt by shifting down at too high a speed. They just won't shift until it is safe for them to do so.

Some of this depends on how steep the downhills are, of course. Some of our grades require low gear at 25 mph or so, and the brake heat can be smelled.

The technique Rusty mentioned on braking is very, very important. It can make the difference between boiling your fluid and not.

Oh yes, if you do any downhill work at all, change the brake fluid yearly, and use one of the fluids mentioned in earlier posts. http://barthmobile.com/eve/forums/a/tpc/f/3631087061/m/...181088061#9181088061

Did your mechanic change the fluid completely? What fluid did he use? Was it from metal cans or plastic bottles? Or was it from a bulk dispenser? Old fluid boils. Economy fluid boils very soon, and ordinary, decent name-brand fluid boils only a little later. Use the best. It is very cheap insurance. And, if you do not choose to downshift, then the best brake fluid is even more important.

One more thing............be aware that sometimes both feet on the brake pedal can give you a little more braking when things get dicey. I have never had to do this, but I know a couple of people who saved things by doing so. When going down steep hills, tilt the steering wheel full aft so it can take the strain of both feet pressing hard on the pedal. It is very upsetting to have the tilt mechanism suddenly release at such a time. And it will.

I do not intend any of this to be alarmist, but forewarned is forearmed, if I may indulge in platitude.

Moved Reply:

What say you, 454 experts, can you help me out or do I need to get a tach before Sept?

Moved Reply:

We drove from northern Illinois to Ashville North Carolina in two days. The whole second day was up and down Kentucy, Tenn., and N. Carolina. I was able to keep up with any truck and pass if needed. No problems with breaks, but we do rest stops for my wifes back problems. We have not pulled a toad yet but plan on it with a Saturn and Break Buddy, no need to go half way on safety. All who wander are not lost.

Moved Reply:

Thanks Sloop, your Barth and mine are comparable in size so think I will be fine. Been driving 51 years so experience should help. lol

I've received several requests in the past to help someone out via a PM. I don't mind doing it, it's just that the lesson is closed to one person and no one else learns from this.

quote:

Originally posted by Mary Ray in a PM to me:
I am very interested in knowing how to change the brake fluid in my Barth. Tell me how, I am mechanically inclined so I think I can do it.

Mary

In the interest of all, and Bill H's superior knowledge of brake bleeding and brake fluid types, I wanted to hear other points of views too. The last time we had this discussion, Bill H pointed out something I never thought of and Rusty pointed out the correct fluid types to use and not mix.

Although two people make easier changing the fluid and bleeding the brakes, one person can do it with the proper tools:

1. Open-end wrench of the proper size to fit the bleeder nipple.

2.a. About 4' of 1/8" or 3/16" (ID) clear vinyl tubing.
2.b. Small nut to thread onto the tubing (as a weight)

3. Plenty of fresh DOT3 brake fluid. For a system the size of a Barth, I plan on having at least three quarts on hand.

4. Rags.

5. Plastic or glass container for bleeding (preferably one that's sealable).

6. Another container for spent fluid.

7. A couple of 1 gallon zip-loc plastic bags.

NOTE: Brake fluid is an excellent paint remover. If your brake cylinder is 'way up inside thew cowl like my Breakaway, also get some large plastic trash bags to protect from spillage!

NOTE: Some bleeder screws DO NOT have a nipple; one person can't flush and bleed the system if this is the case. Check all four corners first.

Here's how I do it solo (the engine is off):

a. To flush, start with the cylinder/caliber closest to the master cylinder (left front). This is the opposite of bleeding, and the reason is we want the fresh fluid to be "upstream" from the old.

b. Place the tubing (nut end) into the discard container (6.)

c. Remove the cover on the master cylinder reservoir. If there's a full rubber gasket (and there should be), remove and place in a zip-loc bag. Replace the cover loosely (we want air to enter the reservoir and vent the system at this stage).

IF THERE ISN'T a gasket, STOP - get a gasket! These gaskets have pucks (expandable, accordion-pleated sections) in them that allow the reservoir to drop as it keeps the master cylinder full while keeping air (and moisture) out of the fluid.

d. Slightly loosen the bleeder nipple.

e. Attach the other end of the tubing to the bleeder nipple, and loosen until fluid flows freely.

When there's a couple of inches of fluid in the container (covering that end of the tubing), you can speed things up by pumping the brake (Press slowly, release quickly). Gravity will prevent the spent fluid from returning to the brake cylinder.

Only empty the reservoir - when it's down, stop pumping the brake. We're going to flush the master cylinder in the next step.

f. Fill the reservoir with fresh fluid (recap the container immediately - brake fluid will absorb moisture).

g.1. Pump the brake pedal some more - check frequently to see that the reservoir doesn't become empty. You will see when the lighter new fluid replaces the darker old fluid in the tubing and the container.

g.2. Allow the reservoir to become nearly empty, then repeat. This will flush the master cylinder.

h. With the bleeder still dribbling, close it.

i. Repeat g.1. next for the right front, then the left rear, then the right rear.

j. Now you're ready to bleed the system. If you've been careful not to allow the reservoir to become empty, there should be very little air entrained. Top off the reservoir.

k. Fill the container (5.) with about 4" of fresh brake fluid; transfer the nut-end of the tubing to this container.

l. Start with the right rear brake; crack the bleeder (only enough to loosen it).

m. Attach the other end of the tubing to the bleeder nipple, and open no more than one turn. Look for bubbles in the tubing; they'll appear first at the topmost section.

n. Pump the brakes (apply slowly, release quickly) several times, then back under the coach and check the tubing for air. If none is seen, close the bleeder.

o. Top off the reservoir and repeat l., m., and n. for the left rear, then the right front, then the left front.

p. When done, press the pedal, checking for firmness. Pump it a few times. The resistance should be felt at the same position from the first to last application. If not, repeat l. though o., in the same order as above, until the position is consistent on each application.

q. When p. is OK, start the engine and again check the position for consistency. It'll likely be lower than before; we're not concerned about the actual position here (except for all-wheel disc brakes), just that the point of max resistance is at the same position, but it should be well off the floor. For disc brakes, the position should be proper, well off the floor.

If the position is low and you have drum brakes, this is a sign that adjustment is in order. Most units will have automatic adjuster, and most can be made to adjust the brakes by backing up and braking sharply. Do that in step s., below.

r. Top off the reservoir, reinstall the gasket with the pucks retracted, and replace the cover.

s. Test drive. Obviously, start slow, and speed up; if they work OK at 20 mph, they'll do fine at 60 mph.

Container 5. can be resealed and used for subsequent bleeding, and that fluid won't reenter the system. The old fluid (container 6.) can be disposed of; some public entities require it to be treated as hazardous waste, but it can be effectively neutralized by mixing with lots of water (now you know why we don't want any moisture in the system), but DON'T pour it into the sewer system...

Thank you Rusty for the excellant instructions. I will print them off so they will be handy in about a month when the weather clears up enough to tackle this job. Now what do you know about a 1990 Isuzu Amigo that has a leaking brake booster, lol just kidding, and thanks again.
See you in Chattanooga

My Barth is only two years newer than yours, I would not have any problems driving in the mountains. I have been to Gatlinburg TN many times with no problems. Not too often I see a Barth OLDER than mine. One more thing I can add to conversation is make sure you have a fresh set of quality belts. If the belts were to come off the hydroboost system you would loose power brakes AND power steering. Not good when descending long steep grad. The same thing would happen if the engine quit running, you would have one stab at the brakes before the power brakes were lost. I recommend anyone with the hydroboost system to find a safe place and turn the engine off while they are moving. This way you will be able experience what you have to deal with if you loose the hydroboost system. My Barth is light enough that with enough room I can stop it. With some of these big SOB's on GM chassis I dont know what you would do to stop, the hand brake would be useless. With good maintenance and if you use your head you should not have a problem.

Neil.

"What say you, 454 experts, can you help me out or do I need to get a tach before Sept?"

No. Since you don't do your own work (as we "experts" do) a tachometer isn't worth the money and effort required.

My suggestion about a tach is based on not overspeeeding the engine, not on concern for the tranny.