1985 Rainbow 27ft RV on Chevrolet Chassis... Help w/my brakes!

[broughy84]

Ok, so as the title of this thread says, I have acquired a 1985 Rainbow Spectra 27' Class A Motorhome. This is built on the Chevrolet truck chassis. I have brake problems on this monster. First a little background... My Great Uncle bought this back in 95 with 41k miles on it. He and my Great Aunt drove it to their campground in the spring and drove it back home in the fall. In 2000 it was parked due to their advanced age and failing health. He passed away this year and my Aunt was put in the nursing home, so I was able to purchase the RV from the family for an amazing low price of $500. The RV now has 44K Miles on it. That's right 3000 miles in 16 years. So it's been sitting in the same spot since 2000.

Now I've done the usually things for something sitting this long.... new tires, new oil, antifreeze, batteries, new gasoline in the tank, etc. The problem is I cannot get the brakes to release. The drivers side front is hanging so I have the caliper off (because I broke the bleeder valve off, then broke and easy out off in the bleeder valve). So I'm replacing that, but the main issue is the brake pedal will not return and the brakes do not release unless you put your foot under the pedal and pull up on them. Anyone have any ideas before I go willie nillie replacing the master cylinder and tearing into the brake linkage???

[MT-2500]

Originally Posted by broughy84

Ok, so as the title of this thread says, I have acquired a 1985 Rainbow Spectra 27' Class A Motorhome. This is built on the Chevrolet truck chassis. I have brake problems on this monster. First a little background... My Great Uncle bought this back in 95 with 41k miles on it. He and my Great Aunt drove it to their campground in the spring and drove it back home in the fall. In 2000 it was parked due to their advanced age and failing health. He passed away this year and my Aunt was put in the nursing home, so I was able to purchase the RV from the family for an amazing low price of $500. The RV now has 44K Miles on it. That's right 3000 miles in 16 years. So it's been sitting in the same spot since 2000.

Now I've done the usually things for something sitting this long.... new tires, new oil, antifreeze, batteries, new gasoline in the tank, etc. The problem is I cannot get the brakes to release. The drivers side front is hanging so I have the caliper off (because I broke the bleeder valve off, then broke and easy out off in the bleeder valve). So I'm replacing that, but the main issue is the brake pedal will not return and the brakes do not release unless you put your foot under the pedal and pull up on them. Anyone have any ideas before I go willie nillie replacing the master cylinder and tearing into the brake linkage???

Time for a rebuilt caliper.

A lot of times the rubber brake hose will cause stop up inside and not release caliper.

To test when it is draging open bleeder.
If draging frees up.
The hose is usually bad.
Or you can open brakre line between hose and master cylinder to see if problem is master cylinder.
Always check for free travel in master cylinder push rod.
Lert us know how it goes.

[broughy84]

Well the caliper seems okay but the bleeder valve is broken off in it and I broke an easy out off in the bleeder valve! So I think it's just going to be easier to pick up a new caliper.

With the caliper off, the master cylinder still hangs. I'm pretty sure my suspicion of that booger being bad is spot on. I think I may need to invest in some PB Blaster and get the torch out for those stubborn bleeders that aren't wanting to open because I have a feeling I'm going to have to bleed the hell out of these brakes when I'm done!

[MT-2500]

Originally Posted by broughy84

Well the caliper seems okay but the bleeder valve is broken off in it and I broke an easy out off in the bleeder valve! So I think it's just going to be easier to pick up a new caliper.

With the caliper off, the master cylinder still hangs. I'm pretty sure my suspicion of that booger being bad is spot on. I think I may need to invest in some PB Blaster and get the torch out for those stubborn bleeders that aren't wanting to open because I have a feeling I'm going to have to bleed the hell out of these brakes when I'm done!

Sorry.
I did not read all of first post or it did not sink in..

If brake pedal sticking unpin master cylinder rod where it goes on pedal and see if pedal free up or will return all way easy..

[broughy84]

Well since the last post I have narrowed it down. I am still unsure if the problem is the MC or not so I'm just going to replace it since its off. I did get the pedal free finally but the pedal still didn't actually fully return after the MC was removed. I kept working it and it finally just started working really well.

I have to have a new caliper and I figure I may as well do the hose and the MC at the same time since I'm under there. I finally drilled out the bleeder valve and well, I kinda got into the threads on the caliper and well hell with it I'll just replace it.

[MT-2500]

Originally Posted by broughy84

Well since the last post I have narrowed it down. I am still unsure if the problem is the MC or not so I'm just going to replace it since its off. I did get the pedal free finally but the pedal still didn't actually fully return after the MC was removed. I kept working it and it finally just started working really well.

I have to have a new caliper and I figure I may as well do the hose and the MC at the same time since I'm under there. I finally drilled out the bleeder valve and well, I kinda got into the threads on the caliper and well hell with it I'll just replace it.

Pedal needs to return free and all the way back.
To work brake lights and release master cylinder/or booster.
Sitting around stuff stiffens up on them.
Does it have a vacumn booster or just reg brakes?
I would suggest.
Lubercate brake pedal hinge/pivot shaft.
And if vacumn booster make sure it is not sticking on release.
Let us know how it goes.
Good Luck

[broughy84]

It has hydraulic booster.

[MT-2500]

Originally Posted by broughy84

It has hydraulic booster.

I have had boosters get stickey.
Up pin/hook brake pedal rod from booster to see which is sticking.
Good Luck

[broughy84]

Ok, So I didn't bother with having the rotors or drums turned or changing the springs in the back. They all looked fine and the test drive netted no shaking under braking so I feel that would have just been burning money that can be put toward something else... The pads are new so are the shoes. We flushed it until the fluid ran clear at all points. Drove her about 60 miles last night and the brakes are very responsive. Did figure out that the timing is off... WAY dogging starting off, bumped the timing up and it's a ton better now although I think my bump was just a shade too far as it has a hard time cranking now... gonna bump that back and get the timing light on it this week sometime. So, thanks to those of you who allowed me to pick your brains. This topic can be retired for now....