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dalej
01-12-2007, 11:04 AM
I went out to check on the bus and noticed oil leaking on the floor. I got down under the coach and it was coming out between the drive wheels on the drivers side. Looks like it might be the seal. Is there a how to with photos to look over on this site?

When my new jack and impact come in, I will look more closely.

ps...Its cold (10 degrees) so I'm not in a hurry. That might have somthing to do with the seal leaking.

Joe Cannarozzi
01-12-2007, 04:49 PM
Dale we had a bad one I had to replace. It wasnt the first time I've done it though. If your thinking about doing it yourself, In my humble opinion if you have never done it before have someone there who has done this before to instruct and help.

I,m gonna throw a procedure out there since you asked.

Your going to need to get an axle nut socket I think its a 4 inch. If you were at POGII and watched Jon pull his axle he was almost there at that point. Once you get the axle out ya back off the outer locknut' lock washer and inner nut and then pull everything as an assembly,the outter bearing, the rims, brake drum, and hub. Another special tool you should have is a wheel dolly but can do the job without it by jacking up the bus just to the point where the duals are just at the point of comming off the ground and with a piece of something flat and smooth on the ground underneath sprayed up with plenty of WD-40 you can slide it all off the housing without the wheel dolly. I'm sure you've guessed I have no dolly:rolleyes:

Retightening to the correct tork is very critical though I have a technique that has always worked for me taught to me by an old mechanic. With a 4 or 5 ft. breaker bar 1inch drive tighten the first outer bearing nut as tight as you can get it then back it off 1/4 turn. Install the lock washer and tighten the outer lock nut with a hammer and chisel

If you do it or have someone do it for you make sure to tighten the outer lock nut with a hammer and chisel. I know that might seem brutal and some mechanics dont see it that way but its when that lock nut comes loose that everything can walk off.

Like I said I did one on the bus and that is exactly how it came off and on and I've done the Pete in this fassion as well and never any troubles but I don't think I would have attempted this repair if I did'nt have the confidence of the prior instruction and help that first time.

dalej
01-12-2007, 04:56 PM
Thanks Joe, I will remember you have done one, for when I get in there. We are planning on leaving in a few weeks and we have a cold spell right now. I don't have a heated barn so I wait to work out there when it gets above 40 degrees.

Jon Wehrenberg
01-12-2007, 05:27 PM
Dale,

You can do it yourself if you want. I think I wrote the procedure and it is available at the POG site, but if you have any questions ask away.

There will be a couple of more difficult items and that will be struggling with the 5 FH screws that hold the brake drum to the hub. I ended up making a "screw driver" by grinding a chisel to the shape of the screw slot and gently "kissing it" with short burst from an impact wrench.

The second issue is the weight of the brake drum itself, but Jan can probably handle that for you.:D

When replacing the seal there is a special tool, but I used a flat wide piece of wood and gently tapped the seal into place.

Hub seals run in streaks. At least they seemed to with my old coach. Once you do the first one you will see how easy it is and from then on you will tackle the job without hesitation.

One caution: On the drive axle the bearings will run dry if you do not fill the cavity in the hub. Once you are underway and driving normally that cavity gets filled by the fluid running left and right from the differential but rather than risk bearing damage be absolutely certain you fill the cavity, either by tipping the axle with jacks, or by manually filling it You know how easy it is to pull the axle because we did that at POG II.

Jon

dalej
01-12-2007, 05:38 PM
Thanks Jon, I will look at POG. You know if I have any questions, this is the first place I will come.

Joe Cannarozzi
01-12-2007, 08:46 PM
Dito Jons comments on the adding lube to the hub berore installing the axle. Cant believe I omitted that. Deffinatly prefill the hub before reinstalling the axle. You can burn a spindle and bearings in as little as a couple of miles. Especially if its the drivers side because of the crown in the road.

Jon from your post I gather you remove the components seperatly. I know you gota have that wheel dolly. Why do you choose not to take everything off togeather. The only reason I can think of is upon instalation theres less chance to damage or nick the new seal going in? Have you ever seen all this removed as an assembly without a wheel dolly as I described? Or did that amaze you and you were just being nice by not commenting on it?

The tork on the axle nuts as well as the job in itself is one of those things that 5 different mechanics might give you 5 different ways to the job. If you ever repacked wheel bearings you know what I'm talking about. Same with the actual removal and replacement of the seal itself.

One other thing. After done and road testing check one hub with the other for heat by touch. If its too tight were most error you will feel it hotter to the touch. Also the slack adjuster, you deffinatly have to back that brake off before you try to pull the drum and readjust it up when done.

garyde
01-12-2007, 11:54 PM
Jon and Joe. What would be the recommended mileage or years, to have the Seals checked and replaced? Is there a preventitive measure? Gary

Joe Cannarozzi
01-13-2007, 12:39 AM
Gary, used to be every time you wanted to do a brake job you had to pull the hub to get the brake drum off. Wheel bearings got checked and seals replaced often. Then came OUTBOARD DRUMS, that allows us to pull the drums without pulling the hubs. Very nice. Much easier and faster. Safer cus more trucks get new brakes more often.

When I need brakes on the Pete I always put them on while paying the tire guy to pull tires for repair or replacment. I can pull the drum and replace the shoes and spring kits fast enough so not to interfer with him and it is because of that outboard drum.

Furthermore you also do disc brakes without pulling the hub.

Because of this fact the axle bearings do not get inspected as often as they used to with the old set-up. Seals as well.

It is my opinion that with the introduction of synthetic lubricants to the equasion, its better now. Synthetics are awsum.

Good question. I would say if we are practicing the Jon method of PM the seals should be replaced at whatever the Prevo maintence manual says for normal inspection interval for the axle bearings.

I also can tell you I pulled the wheel bearings on the Pete at 500000 just to be safe. I run synthetic oil. Very minimal wear. If I had to guess, the seal will probably fail first. An odd thing will wear over a 2 or 300000 miles period and its the seal will actually wear a grove in the spindle. Always check the spindle where the seal rides for a grove. They sell a Save-A-Seal that incorporates a metal ring that is pressed onto the spindle to that point on the spindle where the wear is, combined with a slightly different seal with a bigger innerdiamiter to compinsate.

matsprt
01-13-2007, 04:05 AM
Dale,

Get a piece of 2' X 6' galvanized sheet metal. When you break the seal on the axle have a can under it to catch the fluid. Use that to "lube" your piece of galvanized sheet metal. I, like Joe, always brake them apart as a unit. With a good jack you can raise/lower the spindle to line up perfectly with the hub...then when your ready to put it back together just push it back on. I have a 5 gallon bucket and hand pump to fill the hubs.

Really helps if your on level ground !!

I will not admit to how many of these I have done but Joe's right, after one it's like riding a bike.

Michael

PS...run seals until they fail. You should be able to "catch" them when they start to "seep", but before they really let go. There is no guarantee that a new seal will last longer than a trip around the block.

dalej
01-13-2007, 06:42 AM
Dale,


Michael

There is no guarantee that a new seal will last longer than a trip around the block.


WHAT!!!!! This is nice to know.

PS...Jon I went to the imformation sharing and found the info very helpful.
I just wished it was warm here in the midwest so I could get started.

Jon Wehrenberg
01-13-2007, 08:28 AM
Dale and Joe,

I did take things apart rather than pulling it all at once. My reason was exactly as Joe alluded to and that is to be able to slide stuff back together without risking damaging the seal. I could see what I was doing. Also, everything I do on the bus I tend to do by myself so rather than risk hurting myself I take the long way.

About the lifespan comments.....seals are unpredictable. I had one on the old coach that was original after 250,000 miles and one that had been replaced twice.

Dale has already identified his problem and will take steps to correct it. To all others who are not aware you can have bad seals on every axle. Apart from dripping grease you need to fix the problem immediately because this seemingly annoying but unimportant problem quickly develops into bad juju. First it affects your brakes. Our buses don't stop real well to begin with. Trying to stop with a set of linings that have been greased makes it worse.

But if you choose to ignore the greasy crud and the lousy braking force, start thinking about how many lewbucks this is going to cost when you ignore the problem. When you leak out grease, you are leaking the lubricant for your wheel bearings. When they get dry really bad stuff happens, ranging from bearing replacement all the way to spindle or differential replacement and a possible ride on a flat bed truck.

Even if you do not do your own lubes and oil changes, make certain the person that does checks for leaks at the hub seals.

matsprt
01-13-2007, 12:30 PM
After reading my comments and then Jon's I realize that I made some dangerous assumptions.

First, I own trucks, so I, like Joe, come from that side and as such think in terms of duals. If Dales leaky wheel seal is on the steering axle or tag axle then Jon's method of breaking down the wheel/drum/hub is the easiest unless a wheel dolly is available as Joe noted.

Second, the grease that keeps getting mentioned should really be about 95 straight weight hub oil (yes, years ago they actually used real grease, very unusual now to see real grease used). If you make it a habit of rolling around under your bus then make sure you have a flashlight with you. Look inside the backside of the drums at the seal. If you see an accumulation of "wet looking dust" around the edges of the seal you have one that bears watching.

I suspect that Joe will confirm this, but going under trucks used to involve a grease gun, 9/16 wrench, and flashlight. You would shoot grease, adjust brakes and rattle the drive line all the while checking tires, seals, drums, air lines, u-joints, s cams, airbags, etc....going under your bus should be no different. You can increase your enjoyment with regular preventative maintenance. You minimize the chance of a breakdown.

Michael

Jon Wehrenberg
01-13-2007, 05:45 PM
Drifting a little here, but in addition to the fact I don't have the wheel dolly to pull the duals nor do I feel like oiling up some sheets of steel (that 250 to 300 pounds of tires, hub, brake drums, etc. are just too much for my my poor ole bones) I take advantage of opportunities to pull the wheels because is it my practice that every time a wheel comes off, for whatever reason, I lay it down and polish it.

When the wheels are mounted it is impossible to do a decent job around the nuts or studs, especially on the drive with thehub sticking out. As a result my repair projects are never as simple as what a mechanic would do to get a vehicle back on the road.

Today I am putting new rubber on my steer axle, and I have spent more time polishing than anything else.