Rear Brakes, M375/400, 5 Lug Budd

[ClydesdaleKevin]

Sent: 9/14/2006 8:04 AM

I looked through all the message boards, and while there a lot of related topics, I thought it best to start a new thread so that anyone in the future doing a message search could dial right into this one if they have an M375/400 Chassis, and 5 lug Budd wheels.

Its raining today, and is supposed to rain tomorrow, so after this weekend, I'm going to be up to my elbows doing the rear brakes on the Ark.

I'm replacing all 4 wheel cylinders, the return springs, and the rear brake hoses.  Also, of course, the rear axle seals.

I'm also going to document each step in the process on camera, and post them to the Budd Brake album, Brakes, Budd M375 .  A picture is worth a thousand words, eh?  Sorry the pictures did not transfer in this post.

Additionally, since my shoes are still almost new in pad thickness, I'm just going to clean them up instead of relining them.  This will be accomplished with Easy-Off oven cleaner, and of course brake parts cleaner.

I'll document each step, from cleaning and repacking the bearings, to installing new seals, to replacing the wheel cylinders and springs, the hoses, and then of course bleeding the system.  I'm also going to tackle replacing a couple front brake lines, and the front brake hoses.

To bleed the system, an RV shop turned me on to a sweet little hand-pumped brakeline evacuator, which sucks out the bubbles...one person, Patti, keeps the reservoir in the master cylinder full, while the other, me, simple attaches the hose to the bleeder, opens it, and pumps the handle...there is no pumping of the peddle.  This is how this shop bleeds RV brakes, and I'll let you know how it turns out.  Its 68 bucks for the tool, but it would cost me more to have a shop do it, and then I'll still have the tool if I need to bleed them in the future.  I decided to invest in the tool since I will be breaching the brake lines so much, and last time we bled the brakes manually, without nearly as much air invasion, it took forever to get it even close to right, and even then it wasn't quite right.

Another thing I considered is the Hydrovac Boosters.  If I do all this work, meaning that now my entire braking system is more or less new, and the brakes are still not up to snuff, then the last thing to be replaced, the weak link, is the boosters.  I thought they were crazy-expensive, but Geoff at Alretta has them for just 200 bucks and change a peice, plus a core charge.  Not bad!  If I had known that ahead of time I would have gotten them too, but I spent the rest of my available funds this week on new holding tanks...lol!

And speaking of Geoff and Alretta...WOW was shipping fast!  I ordered the parts late on Tuesday afternoon, and they were delivered by UPS the very next day, by around noon!  I opened the box, and true to form, Geoff sent exactly the right parts the first time around!  Gotta love Alretta!

So, I'm waiting out the rain and will be writing papers all day, but will keep this post active as I work, and post a ton of pictures.

Kev

[DaveVA78Chieftain]

Sent: 9/14/2006 10:36 AM

I have used a vacume bleeder before. The only issue I am aware of with the vacume method is that when the bleeder screw is cracked open, air is sucked in from around threads of the bleeder screw.  The air goes to the vacume pump not the cylinder though.  That can make it difficult to determine if you have all the air out of the system.  From my experience, the best way is to either perform a 2 man bleed or use a 1 man bleeder system.   The vacume pump is still good for doing a lot of other checks on a car though (i.e does the EGR valve work?, etc.).

Dave

[denisondc]

Sent: 9/14/2006 11:22 AM

Dont tell anyone, but I put a light coating of rust-preventer on the threads of the bleed screws and of the flare nuts. If I have it, I use a product that comes as a spray; a marine sealant that dries to a waxy slime. But to avoid contaminating the brake system with this stuff, I only spray it into a teaspoon, then dab it on the threads with a q-tip. If im out of the marine sealant I use the silicone based anti-sieze that works so well on exhaust manifold nuts/bolts.
If you have any anxiety that you will get these products interior to (and therefore contaminating) your brake system.....dont use 'em.

[brians1969]

Sent: 9/15/2006 3:05 PM

I saw at a parts store bleeder fittings that had a check valve built into them. Seems like a neat idea. No more opening and closing the bleeder in conjunction with the guy pushing on the brake pedal......anyone have any experience with these?
They had different sizes for various wheel cylinders.
brian

[moparmotivator]

Sent: 9/17/2006 10:44 AM

http://www.precisionrebuilders.com/new_site/index.html

Precision Rebuilders is also a great source for parts for the old motorhomes.

I got both boosters for less than $170 each.

[ClydesdaleKevin]

Sent: 9/17/2006 8:06 PM

Patience, my beloved readers!!!..lol!!!

Tomorrow, once I have my coffee, I will be running out and grabbing brake fluid, the brake vacumm tool, and the new holding tanks.  The holding tank epic will come later in another post.

I stand firm that Geoff is the best place to buy any brake part that he does stock...and I'd rather pay Geoff at Alretta an extra couple of bucks and know the boosters are the RIGHT ones, built to high standards, than anywhere else.

That said...stay tuned for more!  Tomorrow begins the epic saga!

Kev

[ClydesdaleKevin]

Sent: 9/20/2006 6:19 AM

I got off to a late start, but finally got around to the rear brakes...yay! 

After removing the wheels and axle and drum, I found that my rebuilt wheel cylinders and makeshift dust seals had failed catastrophically...no wonder they were leaking!  The inner tube rubber must not be resistant enough to brake fluid.  Ah well...they are new now!

I put on new return springs from Alretta as well...the old ones were all stretched out.  I also noticed that the cotter pins on the castle nuts that hold down the brake shoes were rusted away...not a trace of them.  So, I put on new ones.  Anyone know if I should grease the shoes under the hold-down washer?  Seems logical, but I'm not sure.

I cleaned up the shoes again, which were saturated in brake fluid...again.  I soaked them overnight with Easy-Off...so this morning I'll clean THAT off with brake parts cleaner, and hopefully they will again be servicable.

Today I'll finish the driver's side brakes, attack the passenger's side rear brakes, jack up the front and adjust the FRONT brake star wheels, and then bleed the whole system.  By the way, I removed each bleeder from everything, and put teflon tape on the threads...this should minimize any air bubbles when I use my cool new brake bleeding suction/vacumm thingy tool!

I have all new brake hoses to install, but all the fittings look pretty crusty...I might put it off for now...I don't want to get into a situation where I have to order new parts and fittings if the ones on there break!  I soaked them overnight in PB Blaster, so we'll have to see how it works out.

Anyway, I added more pics to the Budd brake album...check them out, along with the description!  I'll add more today as the job progresses.

Kev

[ClydesdaleKevin]

Sent: 9/21/2006 7:56 AM

The rear brakes are finally done!  I finished up yesterday.

The passenger side wasn't nearly as bad as the driver's, but its all done now.  New wheel cylinders, both sides, new cotter pins on the castle nuts (shoe holddowns), both sides.  New return springs, both sides.

The star wheels are all freed up.

The bearings are cleaned, and all repacked with grease.

The axles are reinstalled using RTV Blue Ultra as a gasket.

The wheels are back on, both sides.

The star wheels are adjusted, with just the slightest contact to the drums...just a slight hiss.  They will be re-adjusted, along with the fronts, once I finish bleeding the system today.

And DAMN I'm sore today!...lmao!  I give full salute and credit to heavy truck mechanics, I'll tell ya!  I have muscles I forgot I had crying out in agony this morning...ouch!  I'm not used to heavy physical labor anymore...hehehe.

So, today I bleed the brakes, and adjust the star wheels one more time.

Then I start the holding tanks, which HAVE to be finished by tomorrow night.

Pictures are added to the Budd brake album, along with detailed descriptions.

More pictures will be added of the bleeding process.

Kev (The sore and tired Scotsquatch)

[ClydesdaleKevin]

Sent: 9/21/2006 8:39 PM

Success!  The brake bleed was a complete success!

Yes, you guys were right about one aspect of the vacumm bleed...you see bubbles no matter what...even though I covered the bleeder threads with teflon tape. 

So...I probably wasted a lot of brake fluid.

What I did?  I evacuated the brake bleeders, starting with the hydrovacs, one at a time.  The fluid reservoir of the bleeder is 4 ounces.  I did each bleeder, filling the reservoir twice for each bleeder.  Once all bleeders were done, I pumped the heck out of the brake pedal, and let it set for a few hours.

I then did it all again, two reservoirs (8 ounces) at each bleeder, regardless of bubbles...which must have come from the threads.

The result?  The pedal is right up to the top!  One pump makes it harder, but the pedal is right to the top before pumping!

And it stays, hard, even if the engine is started.

So...the conclusion is that the hand pumped vacumm bleeder thingy works!

OK...after I bleeded the system and pumped the heck out of the brakes, I jacked up the rear, and then the front, and did a final adjustment on the star wheels.

I tightened them until they were dragging, all four wheels, and then backed them off until it was just a whisper of contact...

Lets hope the drive is as good as the parked results!

More pics were added to the Budd Brake album, page 8 of the albums.  Mostly it was tools of the trade, etc.

Kev

[ClydesdaleKevin]

Sent: 10/1/2006 9:07 PM

Update!

I just drove 1668 miles, from NJ to TX, and the brakes are perfect!!!

The Ark is braking better, probably twice as well, as it ever has!  And that is pulling the van!  In other words, pulling a fully loaded full size van, I have twice the braking power than I ever did, even when I first bought the Ark, without pulling the van!  I would guess I could even "lock them up" if the van wasn't there!

Thanks Geoff for just the right parts, and thanks Tom for all your help...and thanks to everyone else for all their own brake posts to make the job doable!

And yes...the vacumm brake bleeder is worth the damn money!

Kev

[denisondc]

Sent: 1/8/2008 10:30 AM

And the members with newer motorhomes will be looking forward to your saga/depiction of rebuilding the brake calipers.

I have 'rebuilt' calipers on our familys old cars, and find they work well for several more years - (unlike wheel cylinders for which 'rebuilding' may only get you home from the vacation before they start leaking again). The 'rebuilding' doesnt amount to much work, once you know how to get the pistons out of the calipers, and havent snapped the bleeder screw off while trying to get that loose.

[ClydesdaleKevin]

Sent: 1/8/2008 8:39 PM

LOL Dave!  I don't know if I would bother rebuilding the calipers...the Chevy P30 chassis parts are dirt cheap and easily available.  I would probably spend almost as much on a rebuild kit as buying refurbed calipers, once I turned the old ones in as a core. 

Eventually I want to bleed the brakes on Excalibur...not because they are squishy or anything (they work perfectly!), but I want to change the fluid...lol!  I don't know HOW old this fluid is!  Its not really dirty, but its murky.

My only real mechanical issue right now brake-wise is that the brake booster runs off the power steering pump, and the power steering pump leaks a little!  On the trip from Texas to Florida, about a thousand miles, I lost about 2 ounces of fluid...not TOO bad, but in my experience, leaks only get worse, not better.  It leaks around the steering gear apparatus...I have to clean it all up one day to pinpoint the leak.  I'm too busy in Tom's backyard in the In-Tents Woodshop right now building catapults to do much of anything!

Kev

[denisondc]

Sent: 1/9/2008 7:04 AM

The leakage from the steering box is most likely the top seal, where the steering shaft is. Not easy to reach unfortunately, but better than if its leaking around the pitman shaft. I replaced that top seal on mine when it was losing a pint can of p.s. fluid per 400 mile driving day. But then I dont have hydroboost brakes.
If the leak is from the pitman shaft - Step 2 in the replacement process is to drop the steering box from the vehicle. Step 1 would be locating a replacement Saginaw steering box from another P30.

[toddabney]

Sent: 1/9/2008 8:49 AM

hey gang, what about using silicone brake fluid after everything is re-built? i have been told that the only way to use it is on all new parts.true or false?  thanks to all.i have learned so much reading all the info there.take care,todd

[denisondc]

Sent: 1/9/2008 6:24 PM

The following is my opinion - not to be confused with fact. As I understand it, the reason for using the silicone brake fluid (DOT-5) is because its not anhydrous - wont absorb water from the air; and the metal parts of the brake system will last longer. But unless you got all of the old fluid out, you could still have water in the system; mixed with the old fluid - that would continue to cause corrosion and make wheel cylinders stick or leak. Since the dot-3 kind of fluids are highly miscible with water, they prevent ice from forming, even when its really cold; thus the reason for their use.
I dont think the DOT-5 silicone fluids mix with water, and I dont think they blend with DOT-3 either. My understanding is that they just co-exist, like the liquids in a lava lamp.

I dont know how I would ever get 100% of the old fluid (& any contaminant) out of assemblies like the hydrovac boosters. Nor am I convinced that all of the rubber/plastic parts (some of them predating DOT-5) inside the current system would be compatible with a silicone based fluid.
If someone else does it, I hope they will give us a report on their results - not just the week after they do it, but a year or so and a few thousand miles later.

I can imagine 3 reasons not to use DOT-5 brake fluid. 1. If it was really the answer to problems with olde brakes, the automakers would be changing already & bragging about the improvement. 2. I dont think there is any foolproof braking system (certainly not air brakes), and its a good idea to open it up,dismantle things and examine the parts every few years anyway. 3. If I am in an accident, I dont want an ins. investigator to be making a case that my modified brake system meant the accident had to be my fault. I have a relative who did that kind of work for his employer (auto insurance firm) before his retirement.

[Oz]

Sent: 1/9/2008 9:39 PM

DOT 5 and DOT 3 will not mix.  Like oil and water.  I found that out by accident.  The DOT 5 is clear and heavier than the pinkish DOT 3.  It will rise to the top, or move around the lines like air bubbles.  Also, DOT 5 is very caustic.  I found that out by accident too... and I really don't want to describe the details, it was a horrific mess...

[Slantsixness]

Sent: 1/10/2008 5:13 AM

this link got deleted:

http://en.wikipedia.org/wiki/Brake_fluid

Since its wikipedia, I would say only that "you get what you pay for" as  far as the validity of the information provided there. I have found Wikipedia flat out wrong, distant or misinformed in several instances, brake fluid not being the case in those instances.


Brake fluid opinion...from me? Well... I'll say this:

If you change all of your brake lines (like I did) and all of your Wheel cylinders, calipers, proportioning block (like I did)...etc...
Then:

Use whatever is available on the shelf... and use only that. If it's DOT 5.1, then use ONLY DOT 5.1 (ok..I'm taking Wikipedia's word that it's actually called 5.1)
If it's DOT 4.... use ONLY DOT 4. OR use DOT 3 and only DOT 3.

Just don't ever use Castor Oil (no, I didn't say "Castrol" brand... I said CASTOR oil A.K.A. DOT 2 )

Don't mix 3, 4 or 5.1.... there's a reason they have different numbers, the same as why there is "ATF", then DEXRON II,III &IV, TYPE F and +3 & +4.. and you 'd better not mix those, for sure! (or your transmission will be toast).

Can you clean out all the old brake fluid to change over to a newer fluid?
Well... yes...but it's not easy. Just keep the fluid fresh: change it every year. Then no matter which fluid you use, it will remain fresh and "within specification".
 
Alright already....
enough with the borish post.

Tom

[Slantsixness]

Sent: 1/10/2008 9:43 AM

Has anyone ever gotten brake fluid (not castor oil) in their mouth accidentally..

I can see why it eats paint.... Tastes horrible.

I had a brake line give out on me when I was under a car bleeding the rear wheel cylinders. Got in my eyes, mouth, all over my clothes. It's been awhile, but I can rememder the taste and the stinging in my eyes... really didn't do anything to the clothes after a good wash, though.

What an awful taste. Like ransid olive oil with burnt orange peel in it. Yuck.

[denisondc]

Sent: 1/10/2008 2:09 PM

I have tasted brake fluid (dot-2 & dot-3) over the years, usually when trying to siphon old fluid from a master cylinder reservoir. I dont agree with the Wikipedia article where it says that DOT-2 is "essentially" castor oil. Maybe they meant "Castrol" brake fluid from the 1960s. It was supposedly compatible with DOT-2, but it had a nicer camphor smell. My opinion of Girling brake reliability is about the same as my opinion of Lucas Ignition part reliability. (Not good).

[kilroy75633]

Sent: 3/16/2008 7:27 PM

Another way to bleed brakes is, I built this thing after looking on internet one night at brake bleeders.   I have used it on cars but not on motorhome,

I took a 1 gallon pesticide sprayer and cut the spray head off.
Then bought extra master cylinder cap and drilled out top so I could put a fitting in the top. I attached the spray head hose and put a little back flow fitting in the hose so the fluid would only go one way..Put the master cylinder cap on and then brake your bleeder screws at each wheel and fill the 1 gallon jug with brake fluid and start pumping, It will force the fluid down to each wheel and push the air out.And the fluid in the jug will keep master cylinder full.But make sure your cap is on good or you will have a mess. When you see only fluid come out at each wheel tighten the bleeder screw.  Relieve pressure on spray jug take off and put your regular master cylinder cap back on.

Hope this helps some.

[brians1969]

Sent: 3/17/2008 3:19 PM

I got brake pedal!! I replaced the master cylinder, every wheel cylinder, hoses, shoes, and all the metal brake lines (there is alot of brake tubing on d24!)

I built the power brake bleeder from a garden sprayer (plans are on the internet) and it worked prettty well,except for some leaking around the cap gasket. It got the air out quickly! So much better than the buddy system.

Road trials soon!........
brian

[ClydesdaleKevin]

Sent: 3/18/2008 5:07 PM

Horray!!!

Isn't it an awesome feeling when you do something yourself, and it works beautifully?  And you have the satisfaction of knowing that the job was done right, and you saved big bucks!

Kev

[bigoak54]

HI, new member with a new to me 72 on the same chassis.  we found ours after it spent 20yrs in a barn.  all original, but more work than i had planed to do from it sitting so long.  fuel tanks, all rubber lines rotted out and brakes gone.  i had to replace all of the rubber vacuum lines, master and wheel cylinders.  now it seems the one rear proportion valve is bad and i can not find it anywhere.  does anyone her know the current part numbers for it, a source to get it at or a Winnebago junk yard?  we have yet to drive it and are most anxious to put it all back together and post some pictures. 

[DaveVA78Chieftain]

Not for sure what you mean by "one rear proportion valve".  Proportion valves are normally only used on disk front / drum rear systems.  Far as I know you have a all wheel drum system like described here: http://dave78chieftain.zxq.net/M375Late.html

If that is not the setup you have, then pick the correct one from here: http://dave78chieftain.zxq.net/DodgeRBrake.html

Need to know exactly what part you are looking for.

Dave

[bigoak54]

Hi, thanks for getting back to me.  it is the M375 late system with the two hydrovac units.  it is the valve between the master and the two back hydrovacs.  it has four lines on it.  two go the back hydrovacs, one to the front brakes and one going in from the master.  it this enough info for you?

Steve