Auto Park Brake converted to Manual Lever

[JerryPeck]

Originally Posted by tropical36

How much does your toad weigh? Are you over with the combined weight? I'm thinking it's hard not to be, unless one is towing a smart car or the like.
Again, I'm thinking that many are, and like someone once said....Nothing has broke, fell off, or any other mishap, as yet. Do have some concern about climbing in the Rockies though. We have done so more than once, but without a toad.

I am sure that we are over the combined weight, have not weight it yet for that. We tow a 2011 Chevy Malibu on a tow dolly - with electric brakes - many tow on a dolly without electric brakes, I want all the help I can get. That is another reason I want the tag axle brakes to work - everything helps.

We used to tow a 2002 Chevy Malibu, but gave that car to our daughter and bought the new a year ago.

We don't plan on towing the toad in the mountains, only in flatland Florida. We have compared the cost of driving the motor home (gas mainly) to the cost of renting a house in the mountains (we usually go to the NC mountains) and we can rent a car (no mountain abuse on our car) and rent a house overlooking the mountains, for the less than the gas cost to drive the motor home there.

Besides, there are several 6%, 7%, and 8% grades of 3 miles or so to get over. We used to have a 38 foot 5th wheel and F350 diesel dually 4x4 crew cab long bed and could pull that 5th wheel (combined weight was almost 23,000 lbs) over those mountains at 60 mph and actually gain speed and pass someone if I wanted to ... going up an 8% grade.

Not even going to try in this motor home, it would probably barely pull itself up and over those grades.

[DAN L]

my experience with dot 5.1 brake fluid in motorcycles indicates that it is very wet in less than a year. i reverted to castrol lma dot 4 fluid with good results.

[tropical36]

Originally Posted by DAN L

my experience with dot 5.1 brake fluid in motorcycles indicates that it is very wet in less than a year. i reverted to castrol lma dot 4 fluid with good results.

That's good to know, but just for clarification here, you're not talking about Dot 5 Silicon, are you?

[tropical36]

Originally Posted by JerryPeck

I am sure that we are over the combined weight, have not weight it yet for that. We tow a 2011 Chevy Malibu on a tow dolly - with electric brakes - many tow on a dolly without electric brakes, I want all the help I can get. That is another reason I want the tag axle brakes to work - everything helps.

We used to tow a 2002 Chevy Malibu, but gave that car to our daughter and bought the new a year ago.

We don't plan on towing the toad in the mountains, only in flatland Florida. We have compared the cost of driving the motor home (gas mainly) to the cost of renting a house in the mountains (we usually go to the NC mountains) and we can rent a car (no mountain abuse on our car) and rent a house overlooking the mountains, for the less than the gas cost to drive the motor home there.

Besides, there are several 6%, 7%, and 8% grades of 3 miles or so to get over. We used to have a 38 foot 5th wheel and F350 diesel dually 4x4 crew cab long bed and could pull that 5th wheel (combined weight was almost 23,000 lbs) over those mountains at 60 mph and actually gain speed and pass someone if I wanted to ... going up an 8% grade.

Not even going to try in this motor home, it would probably barely pull itself up and over those grades.

Well, we're not talking Diesel here with our rigs, but having said that, I have no complaints about the pulling power of the 7.4 so far. In fact it's much better than I could have ever imagined and would be even better with a six speed Allison behind it. It's been up and down the Rockies and the Appalachia's and has even passed some DP's, but still not saying that it wins hill climbing races and I will only allow it to rev just so much, whether it's well below red line or not. Now pulling over 2 tons might change my perception here, but still have no concerns in that dept. as long as it doesn't overheat (never has) the engine or the tranny and it would be nice to have a tranny temp. gauge on these rig, instead of some other, both expensive and worthless crap.
As for the economics of RVing vs renting somewhere, I don't even attempt to differentiate or calculate. I just refuse to leave home when traveling, besides the hobby and lifestyle of it all.

[tropical36]

Originally Posted by JerryPeck

I'll have to look up the year of the chassis on my 1998 Trop-I-Cal, but I do know that it was a near end-of-model-year unit because some of the items match up to 1999 model items, such as the leveler pump unit and the valve plate. I've met another 1998 Trop-I-Cal owner twice while camping, again just last weekend, and stuff on his is laid out different than on mine.

Mine does not have that yellow button you keep referring to for the APB, there is a rocker switch on the dash which operates the PB when not in park and you want the PB on. The APB comes on when put into Park, the APB light on the instrument panel comes on, the PB light did not come on until the PB switch was switched to on. Now, after the PB lock-up and the repairs, both the APB light and the PB light come on together when placed into Park, or when the PB switch is switched on. Just further evidence that they messed some things up.

They also blew a fuse for my levelers, took me a while to find a manual for the levelers, then to trace down the problem: they changed the wiring up and put +12 V on a wire to the leveler controller pad, when I traced things down using the manual, that wire with +12 V was actually supposed to be the ground wire tied back to the chassis ground and to the battery ground. I could not follow that wire, so I cut it loose, capped the end, and connected the ground wire from the leveler controller to a known chassis ground. I then traced a blown fuse down to one of the fuses in the controller pad, replaced the fuse, and the levelers now work.

I've decided that I need to do as much as I can on this as service people apparently do not understand these chassis very well. As evidenced by you stating that most service people are apparently not even aware of the tag axle brake being separate and independent. I have a lot of learning to do on this as I trace things down and repair them.

Service of any kind, besides being expensive and sometimes unnecessary, can be very scary as well, especially when it comes to AP repairs. As for brake specialist in general, there's not much excuse for it, when even you and I know better.
Your rocker switch and my yellow knob, I'm guessing, is a house thing and mine is located over on the left wall under the driver's side window along with the jack levelers. The yellow knob is probably more pronounced in it's operation and has less chance of operating by mistake, but either way they do the same thing and only have to cut 12v ignition voltage to default the AP in any gear or out, no matter and sure wish I could depend on it for an emergency brake as some have stated here.
Let us know what you find with the tag axle master cylinder and meanwhile I'll check into some part numbers, if you indeed plan to rebuild it. I would be interested in knowing how that might go, as well.

[tropical36]

Originally Posted by tropical36

Service of any kind, besides being expensive and sometimes unnecessary, can be very scary as well, especially when it comes to AP repairs. As for brake specialist in general, there's not much excuse for it, when even you and I know better.
Your rocker switch and my yellow knob, I'm guessing, is a house thing and mine is located over on the left wall under the driver's side window along with the jack levelers. The yellow knob is probably more pronounced in it's operation and has less chance of operating by mistake, but either way they do the same thing and only have to cut 12v ignition voltage to default the AP in any gear or out, no matter and sure wish I could depend on it for an emergency brake as some have stated here.
Let us know what you find with the tag axle master cylinder and meanwhile I'll check into some part numbers, if you indeed plan to rebuild it. I would be interested in knowing how that might go, as well.

OK, here we go with the Tag Axle braking info and something I got from an RV.net member some years back. You might still be able to locate this individual for even further information.
"I have the exact same setup on my Tropical. My cylinder was also dry when I purchased. After filling, the fluid was escaping into vacuum booster due to worn seals in master cylinder. I contacted Mor/Ryd and was told the part was no longer available but a complete unit with master cylinder, booster and proportioning valve was $750. Could be installed with "minimal" modifications. I removed my cylinder and after hours of searching I located a rebuild kit directly from Bendix for $11 plus S/H, $23 total. I rebuilt cylinder and have no other problems. The part number for mine was Bendix 22979 the master cylinder part # is 011049. Any mechanic can rebuild your unit if it isn't too damaged from running dry. If memory serves me the bore was 1 3/16 which is not a standard size. I purchased mine from the local Fleet Pride dealer. Good luck and let me know if you need any other info.
By….2Scampers
NC
New Member ….rv.net
Joined: 04/24/2007"

[the_dieter]

Wow Dayton Air Brake Chamber for $26.73...get out the car! One of those attached to the short pull cable to the parking brake drum with the small compressor and tank would sure be simple and reliable.

All the best, Jack

[iRV4FUN]

Got my hand brake today and have re-thought what I want to do. I’m considering a manual e-brake override system. Meaning; when I’m in motion I can pull the handle to override (“cage”) the J71 system so when it fails, I can safely find a place to fix it. This will give me peace of mind when I’m pulling my toad at 65 MPH. With the ultimate elimination of having to climb under my rig at night, on a 5% grade, 4 lane highway, in the middle of a dangerous thunderstorm.

Admittedly, I have yet to work out all the details. But, feel the fulcrum spring thingy is where it’s at. It may be possible to run a separate cable and purchase a longer clevis pin to attach the new cable next to the original J71 cable. Any comments or thoughts?

[JerryPeck]

Originally Posted by tropical36

I removed my cylinder and after hours of searching I located a rebuild kit directly from Bendix for $11 plus S/H, $23 total. I rebuilt cylinder and have no other problems. The part number for mine was Bendix 22979 the master cylinder part # is 011049.

I probably will not be able to get to work on the tag axle rake for a couple of weeks, however, after a few internet searches I found a possible source for that master cylinder repair kit: http://pricing.cccparts.com/Web%20fi...BDX-010112.pdf

Near the top of page 4: BDX 022979 KIT BRK SVC 1 22.03

I sent an email to their store in Miami (the closest one to us) for more information, such as the master cylinder bore size.

This is their web site: Home Page

I will let you know what I find out.

Thank you for all the excellent information.

[DAN L]

Originally Posted by tropical36

That's good to know, but just for clarification here, you're not talking about Dot 5 Silicon, are you?

not silicon fluid 5.0.

i used a motorcycle specific (i don't remember the brand) synthetic 5.1 that is interchangeable with dot 3 and 4. i found that it worked, (much higher boiling point) but not for very long.
the same company made motorcycle specific liquid coolant that worked very well.

[the_dieter]

iRV4FUN:

Good start! What I would do is make a list of all of the conditions; shift lever positions, brake on or off, ignition on or off, kids in a fight that has to be broken up, and make sure that all conditions are not only safe, but fit normal expected actions.

For me, locking out the APB manually while moving and then having to remember to disengage the lock before the APB applies the parking brake with its crushing force would be tedious.

I got a start on cleaning up that gordian knot of wiring today which is the first step toward wiring up the two warning switches.

Surprisingly, when I moved the mass of wires from in front of the power steering reservoir, I found that the silver thing above the filler cap is part of the coach body and it keeps the dip stick from being able be lifted above the neck of the reservoir. Since I had to use both hands to snake the filler cap/dip stick out, I couldn't see what was keeping me from getting an accurate reading. This is going into my RV joke book.

Best wishes, Jack

[tropical36]

Originally Posted by DAN L

not silicon fluid 5.0.

i used a motorcycle specific (i don't remember the brand) synthetic 5.1 that is interchangeable with dot 3 and 4. i found that it worked, (much higher boiling point) but not for very long.
the same company made motorcycle specific liquid coolant that worked very well.

OK then, and thanks for the info. We'll definitely keep this in mind. Can't hardly find the stuff in an auto store anyway and in many cases, they never heard of it and think you're talking about Dot 5.

[tropical36]

Originally Posted by iRV4FUN

Got my hand brake today and have re-thought what I want to do. I’m considering a manual e-brake override system. Meaning; when I’m in motion I can pull the handle to override (“cage”) the J71 system so when it fails, I can safely find a place to fix it. This will give me peace of mind when I’m pulling my toad at 65 MPH. With the ultimate elimination of having to climb under my rig at night, on a 5% grade, 4 lane highway, in the middle of a dangerous thunderstorm.

Admittedly, I have yet to work out all the details. But, feel the fulcrum spring thingy is where it’s at. It may be possible to run a separate cable and purchase a longer clevis pin to attach the new cable next to the original J71 cable. Any comments or thoughts?

I like the idea that you're re-thinking your decision on removing the AP
As for pulling the handle, I keep thinking a long handle and one with a ratchet, so you can jerk it an inch at a time. Just saying...
For the idea on the clevis pin, I'm thinking maybe another hole and another clevis with it's own pin in the arm. Much like with the drawing I posted of a hand brake combo, but going in the opposite direction. Again, just saying and this could be quite an undertaking if it will work. Pulling on any cable to collapse that super heavy spring just doesn't sit right with me for some reason.

[iRV4FUN]

Originally Posted by the_dieter

iRV4FUN:
... For me, locking out the APB manually while moving and then having to remember to disengage the lock before the APB applies the parking brake with its crushing force would be tedious.

Good points. Add to your list the various noids, fuses, and pumps that need continual replacement.