1997 winnebago brake fire

[noahron]

on a recent trip all my brakes over heated running on the NYS thruway
causing right front brake fire,my brake fluid boiled out of master cyl.
was towed to repair shop, where no problem was found.
any thoughts!!

[Justjohn]

If all your brakes heated up then you had a stuck master cyl. I had occasional stuck slave cyl on my old Bounder prob caused by overheating going over the Rockies causing gummy residue in slave cyl. Cleaned the slave and no more probs.

[W4MBG]

check the brake disks! on my first state inspection a few months ago the mechanic found that both front disks were cracked. in some places all the way through. i had him replace the disks, calipers, pads, and hoses. he also flushed the brake system. according to him, the oem ford calipers have a habit of sticking, thereby heating up the entire front end of the system. i did, in fact, recall an odd smell once, but it went away quickly. between the brake issue and replacing the ball joints it set me back 1700 bux! that hurts since i only paid 1300 for the rv. but it was done overnight, and to my satisfaction.

anyway, check the whole brake system.

[Gary RVRoamer]

If a brake hangs up (sticks on), it overheats and boils the brake fluid. When everything cools down, ot often breaks loose and everything is ok again. It may or may not happen again. Make sure the shop checked all the components carefully, whether disc or drum type brakes. Overheating can warp them.

[Mekanic]

A 97 huh? well it could be that the master cylinder is hanging up from corrision inside. It may look perfect on the inside but be really bad on the inside. I'd first make sure that the brake lines are all a normal distaance away from any of the exh.
What can happen is if not a line can get hot and cause the fluid to expand and this build pressure just as if you are pressing on the pedal then this heats up the pad/shoes and it just keeps getting worse, and worse untile it does what it did on yours. Be especially careful around catilyic convers and back to muffer.

2 causes for this type of problem
1 hanging cylinders at master cylinder, wheel cylinder, or Caliper(s)
2 excessive heat from exh

[Nick-B]

Something tells me we are not getting the complete story here. Please bear with me here "noahron", I'm just confused and genuinely want to get a clearer picture.

You say ALL you brakes were overheated. How do you know it was ALL brakes and not just one?

Then you say that the Right Front caught fire. So we know there was a problem with at least the right front. BTW, we're all glad that the fire did not spread to the coach or you might not be posting here.

Finally you say that the repair shop didn't find any problems. HUH?!? I'm wondering if you need a better repair shop.

Some good suggestions have already been given but one common one that is easily missed is the collapsed brake hose (like the Right Front?). That would cause the brake to lock and not release and is not a visible problem.

If it were me, with the age of the chassis, I would replace ALL wear components.

• Master Cylinder (new - not rebuilt)
• Calipers with new guide pins
• Brake Pads
• Brake hoses

The rotors may or may not be OK to keep using. The Right Front is probably junk at this point.

Don't forget new wheel bearings for the Right Front since they are toasted now. Left Front is probably OK with a repack.

Best of luck!

[Midniteoyl]

Really Really glad you and yours are alright...

I would look at bad fluid.. Polyethylene glycol fluids like DOT3/4 are hygroscopic and will absorb water from the atmosphere. Water causes corrosion, reduces the boiling point, and freezes in the winter. They supposed to be flushed and replaced every two years.

And now that it has boiled, I would replace the Master Cylinder, rebuild the brake cylinders, replace all lines, have solvent bled through, and a good, hi-temp DOT 4 (or better, DOT 5.1) fluid put in...

[Dwight]

Does anyone else see problems with the above recommendations posted by Midniteoyl?

[Midniteoyl]

?? Dot 5.1 is NOT Dot 5 if thats what you mean..

[mfire1339]

No solvent with rubber components. for one.

Mike

[Midniteoyl]

Oh..there is a cleaner/solvent that can be used for brake line cleaning... Though the lines are to be changed as recommended.

What else? If I'm being called out, let hear why.

[noahron]

doe's anybody think this could have been a ABS malfuction?

[Nick-B]

Originally Posted by noahron

doe's anybody think this could have been a ABS malfuction?

Looking back over the posts I don't see where we established which chassis you have. Ford or Chevy?
I'm pretty sure the Ford didn't get ABS until the '99 chassis year. Not sure about the Chev.

[noahron]

Chevy p30 chassis