Steer Axle Oil Seal Project

GnarlyBus · June 04, 2019, 06:32:03 PM

Quote from: chessie4905 on June 04, 2019, 05:53:07 PM
With the bearings cleaned completely, inspect closely the race the rollers ride on. Hold it up to the light and peer inside. Many times there will be large pits in the surface that doesn't show much on the rollers.

Thank you for the tip, I just did this and they look real clean and undamaged.

luvrbus · June 04, 2019, 08:03:02 PM

Quote from: GnarlyBus on June 04, 2019, 06:25:49 PM
I made this tool for the adjusting nut. I used 1" square steel tubing 1/16" thick about a foot long and drilled holes for the 60D nails. All in for $11. It took about 5 mins.

The square tubing should keep the nail shafts from twerking and damaging the dowel holes like someone did before.

While not completely necessary as you can get by with punches or even apparently just tightening it by hand if you've done it enough times, this gives me a little more confidence. Plus, I've got 3 more wheels to do!

I got the 60D nail idea from another thread on here where the guy welded a nut to square tubing which was a cool idea.

That looks good ,the easy way to make a pin wrench is buy a "Cheap" H/F adjustable 12 in wrench and drill 2 holes the size of the pin then it is adjustable ,I have one made by Proto I have had for 50 years

David Anderson · June 04, 2019, 08:51:01 PM

I just went through all this. Opted for oil bath.

https://www.busconversionmagazine.com/forum/index.php?topic=33821.0

Good luck with yours.
David

GnarlyBus · June 05, 2019, 11:35:53 AM

Quote from: David Anderson on June 04, 2019, 08:51:01 PM
I just went through all this. Opted for oil bath.

https://www.busconversionmagazine.com/forum/index.php?topic=33821.0

Good luck with yours.
David

Yes, solid thread. It came along right when I first heard my seal was leaking and it was helpful to me.

GnarlyBus · June 05, 2019, 11:50:25 AM

Its all back together now. I recommend the SKF Plus XL seals. They are very easy to install by hand and seem much less likely to leak.

The hub went back on the spindle without much trouble. My wife handed me the outside bearing and adjusting nut and I tightened it down. I felt the nut bind while spinning the hub and backed it off. Then put the special washers on and the lock nut.

Then I measured the end play. There wasn't any! Plus the hub was binding slightly. It must have been the locknut. So I redid it and when I put it all back together it felt great. I measured the end play by twisting about 20 degrees back and forth while pulling then twisting while pushing. I read these instructions in a meritor manual online I'll try to attach later. It was right at .003 so I called it good.

I trusted the stemco window hub caps but I'm thinking I may track down ones without windows. Or maybe. Make a plate to go over the windowed portion. I read that synthetic grease likes to be vented.

We used the ol' stand on a cheater pipe 2.5' feet out to tighten the lugnuts down in a star pattern. We did it while building up in torque. I did a few about as hard as I could without straining with the 3' cheater and they were real close to standing on it.

This seal replacement job really wasn't all that difficult. I'd encourage anyone who wants to to try to do it themselves.

Bonus tip: Most bottle jacks come with a wimpy two piece pole for pumping. I used a 1/2" ID black pipe 4' long which keeps me out from under the bus. Although it does take a while to pump! The tip is take an angle grinder and grind a slot in the end of the pipe to fit on the air release to drop the jack. Way safer than being under it while releasing the air.

GnarlyBus · June 05, 2019, 12:54:24 PM

Now that I'm at my laptop I'll add a bit more.

I debated whether to order the brake linings and do them at the same time as the hub seal. I decided that I'd do the hub first and inspect the whole area: s cam bushings, brake chambers, slack adjuster, steering linkage, etc. I did clean the brake linings with a few cans of brake cleaner but I'm under no illusions that this will cut it.

Everything in the brake and steering systems in the driver's side axle area looked good. No S Cam play. No giant push rod movement on the brake chamber. The drums measured good as well and don't have much wear at all.

So I'll be ordering the linings from Luke and I'll pop off the tire and drum on the drivers side and replace them then do the complete job on the passenger side before eventually doing the tag axles probably when I go south as they are in fine shape.

I anti-seized face of the hub where the drum makes contact so that it would come off easier next time.

I also had a little surprise when I went to put the tire back on where the body had aired down enough to rest on my worn out bump stops. The tire wouldn't fit under the rubber fender trim so I used the 12 ton stubby to raise it up. That did the trick.

buswarrior · June 05, 2019, 01:27:39 PM

Nice report, and pictures too!

Happy coaching!
Buswarrior

luvrbus · June 05, 2019, 03:41:07 PM

Quote from: GnarlyBus on June 05, 2019, 11:50:25 AM
Its all back together now. I recommend the SKF Plus XL seals. They are very easy to install by hand and seem much less likely to leak.

The hub went back on the spindle without much trouble. My wife handed me the outside bearing and adjusting nut and I tightened it down. I felt the nut bind while spinning the hub and backed it off. Then put the special washers on and the lock nut.

Then I measured the end play. There wasn't any! Plus the hub was binding slightly. It must have been the locknut. So I redid it and when I put it all back together it felt great. I measured the end play by twisting about 20 degrees back and forth while pulling then twisting while pushing. I read these instructions in a meritor manual online I'll try to attach later. It was right at .003 so I called it good.

I trusted the stemco window hub caps but I'm thinking I may track down ones without windows. Or maybe. Make a plate to go over the windowed portion. I read that synthetic grease likes to be vented.

We used the ol' stand on a cheater pipe 2.5' feet out to tighten the lugnuts down in a star pattern. We did it while building up in torque. I did a few about as hard as I could without straining with the 3' cheater and they were real close to standing on it.

This seal replacement job really wasn't all that difficult. I'd encourage anyone who wants to to try to do it themselves.

Bonus tip: Most bottle jacks come with a wimpy two piece pole for pumping. I used a 1/2" ID black pipe 4' long which keeps me out from under the bus. Although it does take a while to pump! The tip is take an angle grinder and grind a slot in the end of the pipe to fit on the air release to drop the jack. Way safer than being under it while releasing the air.

The run out end play is why the method on the newer stuff is different,the old method is almost imposable to get right without guessing a lot because when you tighten the lock nut to the spec the end play changes

GnarlyBus · June 05, 2019, 03:48:08 PM

I hear that. The manual says something like "tighten it until it binds and then back off an 1/8 turn and finish assembly". 'Til it binds? That's not a very objective term to me. So I figured I'd at least use a dial indicator so I had something to measure.

Lots of YouTube videos I saw have the cone in the middle between the bearings so the techs can do them quicker.

GnarlyBus · June 06, 2019, 11:40:17 AM

I'll add this info for the next guy who changes out a wheel seal on an MC-9.

Inner Bearing (Race): Timken 6379 (6320)

Outer Bearing (Race): Timken 557-S (557-A)

If you change the bearings you need to change the races.

Wheel Seal: SKF Scotseal PlusXL 40091 (Premium install by hand) or Scotseal Classic 40086 (Classic install with tool) or National 370066A

I've attached a diagram of how much grease is supposed to be in the hub and bearings. Some people get confused and pack the hub caps with grease.

I've also attached the instructions from Hendrickson for measuring end play that I used.

Hopefully this thread helps someone. That's why were all here, right?!