Ebrake Issues (I hope...)

[jmdaniel]

The saga continues with my driver's side rear wheel. I changed the axle seal a few weeks back, for the third time, and thought I had the leak stopped for good. It's a '77, with rear drums, so I adjusted the shoes as recommended here, and took it out for 10 miles or so. All was good.

I decided to make a beer run this afternoon, to a store about ten miles away. I noticed when backing out of the garage that something seemed amiss; when I pushed in the clutch while backing down a slight decline, I came to a stop. The ebrake was released, but I set it and released it again, and it seemed normal. I thought I may have set the shoes too close when I replaced the seal, and this was the cause for the tight brakes.

I went on my merry way, and about 5 miles down the road, on I-35, heard some honking. A guy hollered that my rear wheel was smoking. I got off at the next exit, and sure as s**t, it was. The inside of the rim had some black powder/dust/scrapings on it, some gear oil, and it smoked for about 5 minutes.

After finding out the liquor store was out of the IPA I was looking for, I took the back way home to the house. Still smoking when I got home, with more black crap on the rim, and some gear oil leaking out. I had it on the slight upward incline, clutch out, in neutral, and it didn't move.

Questions:
1. Ebrake stuck, right?
2. The ebrake can get stuck only on one side?
3. How do I unstick the ebrake?
5. If not the ebrake, what?
6. What are the odds that the new seal did NOT get cooked, and won't need to be replaced? I mean, I'm getting good at it, but do have other things to do these days.

Thanks in advance for any and all help.

 

[land cruiser kid]

It sounds like your wheel cylinder froze and it won't release

 

[Bang Bang]

Same thing I was thinking. No way for it to stop one wheel.

 

[land cruiser kid]

Don't you guys think it's the wheel cylinder especially if it's just one wheel? I would say if he jacks up the rear and can't manually spin that side wheel that it would have to be that.

 

[jmdaniel]

All the wheel cylinders were replaced with new OEM less than 1K miles ago. Not saying it couldn't be that, but I'd be surprised.

 

[land cruiser kid]

All the wheel cylinders were replaced with new OEM less than 1K miles ago. Not saying it couldn't be that, but I'd be surprised.

Are you able to adjust the brakes by turning the wheel cylinder with a screwdriver thru the back of the drum?

 

[jmdaniel]

Are you able to adjust the brakes by turning the wheel cylinder with a screwdriver thru the back of the drum?

I did when I changed the seal, and they moved freely.

 

[land cruiser kid]

I did when I changed the seal, and they moved freely.

Hmmm. Well, I would remove the parking brake drum and see if you see anything screwed up, still wouldn't make much sense if only one wheel was locking up though.

 

[FF LC FREAK]

If you have gear oil leaking out, something else is going on. Are you sure its gear oil and not brake fluid? You say you just put in new seals. So, why the gear oil leaking? But you also said new brake cylinders. Do you have a bent axle or housing that is causing issues? That would explain the messed up seal already. Just throwing out ideas.

 

[lefty b]

So you've replaced the axle seal 3 times so far? Are you putting any lube on the seal lip and/or axle where the seal rides so it isn't run dry for any length of time? I'm with FF, there might be something more to look at. How did the brake pads look when you were in there? If they've gotten wet with gear oil (from the leak(s)), they can drag and cause the brake to stick. Even cleaning them with brake cleaner doesn't get the soaked in oil out. And if one of the new wheel cylinders has gone south, brake fluid can have the same effect. I would pull the drum off and see what things look like in there. Baby might need new shoes, at least on that side.

If it's axle grease that's still leaking, you're either doing a.....ahhh......poor job of installing the seal, or there is something else killing them in short order. Could be a burr on the seal surface of the axle, as stated before, a bent axle. Could even be a plugged breather causing pressure to build up in the housing. Are you sure you are even getting the correct seal? I'd say even if you screwed up installing it once, you should have gotten it the second time. Sounds like plenty of things to investigate.

As for the ebrake, since it is mounted on the back of the transfer case, it wouldn't influence just one side of the rear brakes as it stops the driveshaft from turning. And if you forget IT on, smoke comes out from UNDER the truck, not from a wheel (don't care to tell you how I know this). Shoot a good picture with the brake drum off and post it up. We might be able to see what's going on.

lefty b

 

[jmdaniel]

So you've replaced the axle seal 3 times so far? Are you putting any lube on the seal lip and/or axle where the seal rides so it isn't run dry for any length of time? I'm with FF, there might be something more to look at. How did the brake pads look when you were in there? If they've gotten wet with gear oil (from the leak(s)), they can drag and cause the brake to stick. Even cleaning them with brake cleaner doesn't get the soaked in oil out. And if one of the new wheel cylinders has gone south, brake fluid can have the same effect. I would pull the drum off and see what things look like in there. Baby might need new shoes, at least on that side.

If it's axle grease that's still leaking, you're either doing a.....ahhh......poor job of installing the seal, or there is something else killing them in short order. Could be a burr on the seal surface of the axle, as stated before, a bent axle. Could even be a plugged breather causing pressure to build up in the housing. Are you sure you are even getting the correct seal? I'd say even if you screwed up installing it once, you should have gotten it the second time. Sounds like plenty of things to investigate.

As for the ebrake, since it is mounted on the back of the transfer case, it wouldn't influence just one side of the rear brakes as it stops the driveshaft from turning. And if you forget IT on, smoke comes out from UNDER the truck, not from a wheel (don't care to tell you how I know this). Shoot a good picture with the brake drum off and post it up. We might be able to see what's going on.

lefty b

Yeah, I've been putting grease on the lip of the seal, and the spring area, before sliding the axle back in. The brake shoes were brand new at the time of the wheel cylinders, (which was when I replaced the seal the first time), but have been soaked with gear oil twice now, so I will jerk them out and replace them. I had cleaned them both times (seals 2 and 3), with brake cleaner, but maybe that is one time too many.

As far as what I assumed was gear oil yesterday, I'm thinking it was heat induced; there has been no evidence of leakage since I replaced the seal the last time. I have closely examined the seal surface on the axle, and it appears fine, but not even sure how I would check for a bent axle. The 40 had less than 4K miles in the 10 years since the frame off restore, so there were a few seals that needed replacing, and this axle seal was one of those. It's been about a year since replacement #2 and #3, and I think the reason for the last replacement was I didn't have the seal deep enough. I couldn't find any info on how deep to place the seal, so had it flush with the outside of the housing. This last time, I went deeper than that, after getting a quasi consensus here on MUD when I asked the question. The potential of a breather plug was eliminated awhile back, when I checked for any blockage and replaced the stock Toyota "cap" with a small air filter. And finally, the seal is the correct one, getting them from Lowe Toyota.

I won't get to a picture with the wheel off today, I have to be out at the Circuit of the Americas track, driving a courtesy transport for the LeMans race, (I'd rather be fixing my 40). But I do have a few pics of the last attempt at a seal:

Old seal pulled, and I guess the shoes do look a little dark...

The seal surface before the new one placed. A bit of pitting, but I don't think anything that would prevent a good seal, if the seal was placed correctly.

And the new seal in place, with a quasi bead of gray Permatex as a fallback, as recommended by someone here awhile back:

 

[Pighead]

Have you checked the breather on the diff to make sure it can vent properly?

 

[spotcruiser]

Did you replace your master cylinder before this problem started? There is a pushrod between the booster and the master cylinder and it can fall slightly out of position, if it's not adjusted correctly, preventing the master cylinder piston from returning fully after the brake is depressed and released. So some pressure remains in the system. Perhaps that's what's happening on your truck and it just happens to be showing up at that brake, due to differences of adjustment. I've seen a smoking rear brake (or brakes; it's difficult to remember so far back) as a result of that pushrod.

 

[jmdaniel]

Have you checked the breather on the diff to make sure it can vent properly?

Yep, rodded it out and put an air filter on it.

 

[jmdaniel]

Did you replace your master cylinder before this problem started? There is a pushrod between the booster and the master cylinder and it can fall slightly out of position, if it's not adjusted correctly, preventing the master cylinder piston from returning fully after the brake is depressed and released. So some pressure remains in the system. Perhaps that's what's happening on your truck and it just happens to be showing up at that brake, due to differences of adjustment. I've seen a smoking rear brake (or brakes; it's difficult to remember so far back) as a result of that pushrod.

Brake booster and master cylinder were replaced a couple of years ago, rebuilt booster and new OEM master. They've worked fine since then, so I'm pretty sure it's related to the seal replacement.

 

[Pighead]

Yep, rodded it out and put an air filter on it.

Well, just trying to find the easy answer...

 

[lefty b]

Usually with a master cylinder related issue it affects one END or the other, or both, because of the two brake circuits. With there being only one line feeding both sets of brake cylinders in the rear, the pressure would be equalized between them, and wouldn't apply brakes to only one side.
On traditional drum brakes, with the wheel cylinder at the top as the anchor point, and the bottom more or less "floating", when the shoes get wet, it sort of sucks them bacckward with the clockwise rotation of the drum. And that wedges the rear show up and against the wheel cylinder, while the front shoe isn't doing much of anything. Not sure how that relates to a 40 with it's dual wheel cylinders, but it's probably just twice the fun, with both shoes getting to play. Sucks that they are fairly fresh shoes, but once they get wet (oil etc), I wouldn't trust them.


lefty b

 

[jmdaniel]

All right, lefty b, that will be the first thing I fix. Anything about those pics give you consternation?

 

[lefty b]

I've been on my phone (watch in football at a friends) all day, and haven't got a good look at the pics. I'll take a look later on a pc when I get home.

 

[jmdaniel]

I've been on my phone (watch in football at a friends) all day, and haven't got a good look at the pics. I'll take a look later on a pc when I get home.

Thanks. Here's a tip for you. Become a Vikings fan. Disgust at their play will free up a lot of Sunday afternoons!