BAC Forum
General Boards => Technical Support => Topic started by: Carl Boger on June 15, 2022, 11:27:29 PM
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Can anyone tell me what is involved in replacing the brake lines running to the rear brakes on my 1998 Patriot Savannah.
My Coach is at my diesel mechanic's now because it has been loosing brake fluid, and a rear axle seal leak. Well the axle seal has been replaced, but there seems to be a leak in the brake line that apparently runs over the fuel tank. I am not there right now so I can not verify exactly how everything is run.
Any way the mechanic doesn't have a pit or lift so he is not interested in working on the brakes. I am trying to figure out what is involved in changing out the lines. Can they be accessed from the side panels and storage areas where they run along the frame rails?
I understand from a earlier post that the lines switch from metal lines to rubber lines several times. Are these connections flare fittings that can be unscrewed, or are they mechanical fittings that will need to be made at a hydraulic shop?
Eric I saw in the earlier post that you listed the part numbers for the needed rubber lines. Any idea which line is running over the fuel tank, or more importantly how to replace it and the others.
Thanks everyone.
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Hi Carl,
A few years ago I replaced all break lines in my monterey
I purchased 50' of the brake line, fittings, a flare tool and line tubing bender.
It was time consuming
The rubber hoses at the wheels were available at advanced auto too, bring them to match them.
If you can find a concrete slab and a crawler, the job will be much easier and quicker.
Going over or around the fuel tank is not a problem.
I made sure (except once out of two) to leave a solid line through the storage compartments, had a small leak too.
As far as difficulty, it wasn't too bad. Taking your time will be worth it. just a lot of ups and downs - hence the crawler, concrete floor.
The toughest part is at the master cylinder, it is behind the l/f tire on the monterey. poor planning on beavers part- i think.
Good luck
Tom
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Carl
As tom said the rear line runs inside the driver's side frame rail from just ahead of the fuel tank all the way to the rear axle area
There is a rubber flex line that connects from the steel line over the the master cylinder and another flex line at the rear that drops down the the H frame for the rear brakes where it tees off to go to each rear wheel and arch rear caliper has its own flex line from the H frame to the caliper.
The best way to replace the steel line as tom stated is to use a roll of line and flare it yourself that way you can replace it as a one piece line limiting the number of connections .
The truth is the line runs inside the cargo bays for most of its run and is only exposed to the elements ( rust ) for a short run at the front and rear .
The rear section just outside of the cargo bays is only about a foot long but is way up there and hard to reach if it looks ok you might be able to replace only 6 foot section over the fuel tank with a premade line by cutting the old line above the propane tank and flaring and new end on the old line and a line union to connect to the new line over the fuel tank.
While your there take a good look at those flex lines remember they are 24 years old .
On my coach I took the opertunity to replace all the brake lines both steel and all the rubber flex lines.
Hope this helps
Eric
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Thanks Tom and Eric,
This is kind of what I was hoping for. I hope to at least get it patched up soon since I have a trip planned for next weekend. After that I will not be going out in the RV for 2 months so I will use that time to address all the lines. It was only 96 degrees here today, so perfect time to do a job like this.
Thanks Again.
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Carl
If your going to do a quick fix for the section over the fuel tank
The only real spot to get to the existing line is to get yourself up between the propane tank and the front H beam it's a tight squeeze but doable easiest done by raising the front end and put it on jack stands to get as much room under there as possible.
The flair and union can be made over the propane where there is room to work .
You will find with the gen slide out the connection from steel line to rubber flex line is located in the driver's side frame rail just at and above the gen set slide ( be sure to get the right connection as there are two there one for the fronts a d one for the rear.
Before you get in too deep first make sure the rear caliper bleeder screws aren't siezed.
Hope this helps
Eric
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Thanks Eric,
Looks like I will be getting to this on Monday. Tight access is really my only concern as I am not a small guy. Hopefully long arms will help. I have squeezed myself into that area before so hopefully everything will go well. I should have help this time also so that is already better than normal.
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Well Carl
How'd the brake line repair go
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Took a while. This was more of a patch job. Replaced the steel line running to the rear brakes,hooked everything else back up and bled the brakes. Everything was holding fluid and the brakes worked when I drove it back and forth. It is more than a little tight under there!
It was 10 pm so I decided that I will pick it up in the morning. After this trip I am planning to do a better job and replace all the lines, and probably rebuild the calibers and put on new pads.
That and clean up the frame area and apply a rust inhibitor/converter. This is a job that will take a while, but I will not be camping in July or August. Time to round up some help and get to it.
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Carl
Man that's a big job cleaning and painting the frame I know I've done mine .
The brake calipers are all the same front and rear and are pretty inexpensive for there size as remanufactured parts
If your going to replace the two front brake lines they are almost impossible to do without dropping the fuel tank as they run inside the frame rails and turn and come out through the frame above the fuel tank you may find it easier to relocated them to the out side of the frame rail as I did mine .
Part numbers.
Calipers all four are the same ..............Centric #14179001
Caliper hardware kit ( one per axle) .......Centric #11779003.......... These are the hold downs and bolts to mount the calipers.
Front flex lines ...... (42inches).............. Raybestos # 383373
Flex line ........(40 1/2 inches)...... Raybestos #381081
Flex line ........(39 inches) ............ Raybestos #381082
Brake pads same for front and rear....... Centric. #10602360
Front rotors .............................................. Centric #12079023
Front inner hub seal .................................Stemco #383-0136
Front bearing / hub cap............................Stemco #343-4024
Front inner wheel bearing ........................Bower #HM212049X
Front outter wheel bearing ..................... Hyatt. #3782
Front outter wheel bearing race............. Hyatt 3720
Rear rotors ..............'......sorry I don't have a number for these
Rear axle seals ..............sorry I don't have a number for these
I haven't got any numbers for the rear rotors and bearings as I haven't had to do those yet
Most of these parts aren't too hard to get as they are common medium duty brake parts used on some Ford, international and Freightliner medium duty trucks and school buses.
Hope this helps
Eric
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Thanks Eric!
I may beg a favor from a good friend who owns a trucking company. He can get much better prices than I can and will usually let me just pay for the parts but link them to his account. It has saved as much as 50% in the past.
As far as the rear axle seal, well just put one in on my Rockwell rear axle. It was a National Oil Seals Pert # 370023A. I am sure it can be cross referenced to other brands, but that is what I could get in a timely manner.
Yes it will be a big job, but i just keep running into the next weakest link and I would rather fix them right than patch them together.
The old hard line had been replaced before and they used a compression fitting and attached it to the old line. Well it rusted through again! I patched it together the same way for this trip, but will put it back to the Beaver design when I jump into the big frame project.
When I get home I plan to drive it up on ramps and get it ready to be crawled under safely. For this one I am going to call in a few favors and probably hire a friend to help. Hopefully I will jump on this with all the parts on hand in the next month or so. I am not doing a restoration, but I am trying to make it at least clean and easier to work on.
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Carl
I hope when you repaired that brake line you flared the line and used a flared line union .
The use of compression fittings on brake lines is illegal and dangerous .
Thanks for the seal number I'll add it to my book for reference.
I believe that most of the brake parts where supplied by Dayton as well as the torque rods.
This might help the disc section has all the dimensions
https://www.google.com/search?q=dayton+medium+duty+rotors+listed+by+size&oq=&aqs=chrome.0.35i39i362l15.-1j0j8&client=tablet-android-lenovo-rev2&sourceid=chrome-mobile&ie=UTF-8
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Thanks Eric, It was flared. Just got home didn't have cell service for a few days so no internet. Time to regroup and repair.
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Good stuff , you've got a big job ahead of you cleaning band painting the frame makes the brake work look like child's play. LoL.
A tip to getting the rear of the coach up on jack stands.
Back the coach onto blocks creating enough room to safely get under the coach then with the coach running to maintain air pressure disconnect the lower link end of the two air ride valves and push them up .
When the suspension tops out this will be when the nylon straps come up tight at this point the suspension is toped out you can now place you 10 ton jack stands under the frame rails just behind the rear axle then you pull down the ride height links this will exhaust the air bags and the weight of the coach will now be supported by the jack stands .
Once this is done now you can place a smaller jack under the axle to raise it enough to remove the wheels and giving you access to wheel end brakes etc.
Remember jack stands are rated as a pair not each meaning if the stand says 5 tons each stand is only rated for 2 1/2 tons
Truth be known they are tested well above that but are rated with a large safety margin built in.
The rear of your coach should have a 20,000 lb GAWR so you would require a pair of 10 ton stands to support the rear of the vehicle.
Hope this helps
Eric
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This topic has not been added to in awhile, but I hope it will still be seen by some of you who have done your own brake work, particularly front, on Beavers near my build date, 2001. I have the 33' Monterey Trinidad model. I have had three different truck shops do my front brakes in the last ten years, with very low mileage in between jobs - anywhere from 4000 to 7000 miles. The problem shows up exclusively on the right front side. Generally, it starts while/after descending grades, which is understandable, but I do come down slowly, always use my PacBrake, and operate the pedal gingerly, knowing I have an ongoing problem. The right front begins to smell, then smokes, and occasionally has started little spots of fire on various surfaces of the hub and caliper, presumably from leaking fluids. The shops act dumbfounded and give me no assistance after multi thousand dollar jobs. I won't use them again. I have done all my car and pickup brakes since high school (55 years) but haven't wanted to deal with size and weight issues of my Beaver front end parts. Well, that reticence is finally gone. I've invested in heavy duty impacts, torque wrench, Jack stands, etc. and have started the work. My right front wheel/hub/brake assembly is all apart. I am going to replace the whole brake line system as others have written about, both hard lines and flex. I discovered the phenolic pistons in the most recently installed front calipers were totally frozen in the bores. My problem now is I have found the correct calipers, but not ones that don't have the phenolic pistons that others have said can cause lock up problems. Have any of you been able to find a source for calipers with an alternate piston material than phenolic?
Also, any ideas on whether a defective master cylinder and/or booster pump might be causing some of the overheating? As long as I'm this deep in, I'm committed to doing the whole thing as right as I can. After spending many thousands at shops to no avail, I'm OK with spending a few thousand for the peace of mind that an all "new" system will give me.
Thanks for any advice you might have.
Eric
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Eric
There are a lot of things that can cause the brakes to smoke any of the below can contribute to a tight brake .
1) although technically no a brake problem and hub seal leak can cause smoking and burning
2). Bad or overheating wheel bearings can contribute to number (1).
3) as you described phenolic brake caliper pistons can absorb moisture and swell in their bores.
4) incorrect brake fluid can cause caliper seals to swell and hold caliper piston/s extended.
5) bad or incorrectly installed caliper seals.( During caliper rebuild )
6) moisture the brake fluid causing rush with in the calipers ( the lowest point in the system)
CAUTION moisture also lowers the building point of the brake fluid and can lead to brake fluid boiling and brake failure.
7) caliper slides too tight or not maintained or cleaned properly.
8) bad brake flex lines ( as they get old the inner lining can collapse causing the flex line to work like a check valve holding pressure on the caliper.
9) a bad master cylinder or poorly adjusted master cylinder actuator rod can cause the master cylinder piston to not return back far enough to uncover the compensator port in the master cylinder causing the brakes to drag ( worst when they are hot as the fluid expands has no where to go and applies
pressure to the caliper)
10) on an air over system the treadle valve ( brake pedal) may be sticking and not releasing the brakes fully ( the pedal itself will sometimes get seized)
With that said I assume you have air over hydraulic brakes on your coach ( correct me if I'm wrong ) it may be hydraulic over hydraulic.
The easiest way to diagnose a hydraulic problem is to loosen a bleeder screw when the problem is exhibited if loosening the bleeder screw allows the wheel to turn freely the problem is likely a flex line or master cylinder and not the caliper itself
Your front brake system will have three flex lines one at each front wheel and one at the master cylinder for the front brakes .
Most of these parts are off the shelf parts used on medium duty trucks of the era ( Ford , International , Freightliner.)
BRAKE PARTS
Front wheel bearing inner= Bower #HM212049X
Outer=.Hyatt. #3782
Outer race=. Hyatt =3720
Brake flex lines. Front= Raybestos. #BH383373. = 42"
Raybestos #BH381081. = 40 1/2 "
Raybestos #BH381082 = 39 "
Front hub seal. = stemco #383-0136
Front brake rotor. = Centric 12079023
Front brake calipers = centric #14179001. Or Bendix #55252. ( Note calipers are same right and left and front and rear)
Front caliper hardware kit= centric #11779003 ( this is the guide spring and wedge kit for the caliper mounting) does one axle or two calipers.
Front brake pads. = centric #10602360. Or Dayton D236
Front brake converter with master cylinder = Haldex # N37216c
Below is a link to the centric caliper which states the piston material is steel { I'd assume stainless steel )
https://www.showmetheparts.com/centric-parts/centric-14179001.html
Hope this helps
Eric
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Thanks so much for the quick reply, Eric.
My local FleetPride has that caliper part number in stock.
I'll verify with them the material of the pistons.
After re-reading all the brake problem posts on this forum it appears the
problem with the phenolic pistons is that water in the system causes them to swell.
A periodic complete purge and refill with new fluid should help that situation if I
can't find anything but phenolic pistons.
Again, thanks for all the information.
Eric
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Eric,
This job is pretty much straight forward brake work but the working quarters are tight. Now I am a fairly fit, fairly low body fat,(15%) person, but I am 6'1" and 220 lbs so I don't fit well in a lot of places. I also have a repaired shoulder that doesn't do well with overhead work. If your generator is on a front slide than run it out that helps a lot. The higher you can get the coach also helps! I drove up on ramps raising the coach 4.5 inches, 6 would have been even better, 12 would have been great.
This job is doable, but take your time and break it up into small segments. I was sore for a week after I finished, probably should have slowed down the work but I tend to force my way through.
Hopefully you will git a tip or two out of this,
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As I have continued my project of almost complete replacement of my Monterey brake system I have run into a puzzling situation.
I've tackled the front components first, calipers, pads, booster pump, master cylinder.
The front lines have been relatively easy to trace out, hard to get to, but an understandable path from master cylinder to ABS valve
and on to left and right front wheels. I just started digging into the rear system and have found a situation I am not understanding.
A brake line diagram would be such a help, but I can find nothing like what I am looking for. I made a guess that one long line would
go from the front of the coach and tee into two directions going to each back wheel. What I have found is two long lines going to the
back, one on each side of the coach. At the end of each long line is a tee with one branch easily seen and accessed going to each wheel.
The other branch of the tee on each side goes up toward the floorboard and quickly out of sight. I can't understand where they would be going.
Have any of you who have done replacing of your lines found this situation?
Also, what seems odd is that all the up front steel lines are 1/4", while the two long lines going to the back are 3/16".
Does that make technical sense?
Thanks for any ideas.
Eric
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My best guess would be that someone replaced the rear brake line earlier, and then abandoned the old line leaving it in place. This is a common practice since it cuts down on labor cast. On my coach I replaced the rear line and then just cut off the old line as short as possible without trying to remove anything that wasn't convenient to get to. Hope this helps.
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Ok Eric
It appears your coach has an ABS system on it in which case each wheel will have an individual brake line which will run from the caliper to an integrated ABS
Control valve .
If you've found the ABS control valve it should have 4 brake lines running out one for each wheel end there should also be a tone ring and wheel speed sensor on each wheel
I'm not sure which system Beaver used on the Magnum chassis but I assume it is a meritor wabco system like the one in the link below.
https://graphicvillage.org/meritor/MM0677.pdf
Hope this helps
Eric
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Thanks, Carl and Eric,
On further, and dirtier, inspection today I discovered a couple of things.
There is a long steel line on each side of the coach leading from the ABS valve back to each rear wheel.
It turns out only one side has a tee in it, not both as I mistakenly said yesterday.
The tee on the passenger side turns down to the RR wheel while the other branch goes to the back of the coach into a proportional valve tied into the coach air system. We bought the coach barely used over twenty years ago and I had forgotten that early on I had installed an MG Brake Systems braking system for a prior toad. In prior times my memory would not have let me down as it does more and more these days.
Yes, I have a Meritor/Wabco ABS system very similar to the attachment you added, Eric.
After removing the air conditioner condenser between the rails right in front of the fuel tank it looks like I may have just enough working room to install new steel lines from that valve to each of the wheels.
It's an unpleasant job but the thought of a well working brake system is providing incentive. We love our coach, but the poor braking has been a weak link in our enjoyment of the coach for a long time.
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Sounds like your well on your way.
I found a good gym mat to be a god send for the knees and back when working under the coach
Keep in touch
And good luck