Brake Repair Question

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B8B
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Brake Repair Question

Post by B8B » Sun Jul 17, 2022 8:46 pm

Folks might remember from my "Resurrection of the FrankenMule" article here on the "G" (and published in the MVPA's magazine) that my M274A3 has a variety of parts from other Mule models. One 'good' change was that it has an 'A1 and later' style brake assembly, rather than the smaller and less effective M274 and A3 style. But when I drive it at anything above crawling speed, braking creates a 'shudder' and a grab, lurching it to a halt.

Today I took the brake shoe off and found what could be the problem, Oily sludge had been accumulating in the bottom of the 'Dirt and liquid shield' that the brake shoes are mounted to (and probably to at least the lower shoe). The center drive shaft companion flange was oily, leading me to believe I have a leak from the seal to the center gear carrier assembly.
Mule Brake Assy as Found.jpg
Brake Assembly as found

I'm not ready to delve into seal repair, since my Mule readily 'marks it territory' with leaks from all over, so I'll just try to improve the braking for now, if only temporarily. Tonight, after scraping off as much sludge as I could, I masked off the area around the brake assembly and sprayed red-canned Brakleen brake cleaner (the good stuff!) all over it. Before I go too far, though, I need to know if any brake parts need repair or replacement.

Since I havent done brake work before, here are some pictures of what I see -- what needs fixin'?

The brake pads don't seem too worn, but I can't tell if they're damaged or too 'gunky' to work well.
Lower Brake Shoe as found.jpg
Lower Brake Shoe as found
Lower Brake Shoe after cleaning.jpg
Lower Brake Shoe after cleaning

The brake drum looks OK (to me), so is the brake drum usable as is, or do I need to get it turned or replaced?
Mule Brake Drum after cleaning.jpg
Brake Drum after cleaning
If everything seems usable to y'all, I'll button it up and give it a test drive. Hopefully the degreasing is all it needed. If I need parts or service, I'll get right to it.

Thanks in advance.
'58 M274A3 Mule, SN 10965
'62 M422A1 Mighty-Mite, SN 3741
'65 M416-B1 Mighty-Mite Trailer, SN 11
'97 LTT-HC 'Mule Hauler' Trailer, SN "H.A.C.-054"


Chuck W.
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Re: Brake Repair Question

Post by Chuck W. » Mon Jul 18, 2022 7:30 pm

That's pretty typical for a mule, the pinion seal always tends to leak. If you decide to replace it, I'd recommend you get the original factory seal from John Emery. Some folks will put two National 470548 seals here, but I don't think they seal as well as the original double-lip seal. A good cleanup with brake cleaner and you will probably be OK. be sure the two brake shoe rollers are free and turning; a little anti-seize here will help a lot.

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B8B
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Re: Brake Repair Question

Post by B8B » Mon Jul 18, 2022 8:03 pm

Thanks, Chuck. I spoke with John today and he recommended replacing the seal as well, rather than band-aid it with just a cleanup. He assured me it wasn't too tough a job, so I've ordered his 'kit'. In the meantime, I'll be pulling the brake assembly off the gear carrier assembly and doing some more cleanup.

Always great advice from our Mule mentors.
'58 M274A3 Mule, SN 10965
'62 M422A1 Mighty-Mite, SN 3741
'65 M416-B1 Mighty-Mite Trailer, SN 11
'97 LTT-HC 'Mule Hauler' Trailer, SN "H.A.C.-054"

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Re: Brake Repair Question

Post by Chuck W. » Tue Jul 19, 2022 8:31 am

That's probably a smart move, not a bad job at all. Make sure you clean out the drain holes as shown below, if somebody's been into it before, you may find the holes full of silicone! This lets any oil that gets past the seal drain back to the housing rather than leaking onto the brake shoes.
Image

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B8B
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Re: Brake Repair Question

Post by B8B » Wed Jul 20, 2022 9:55 am

More good advice.

Now, how to get that big center nut off? I’m at the ‘breaker bar’ stage, and it doesn’t want to budge:
DE27A7EE-A251-41A7-94A2-C4E817197D4A.jpeg
Breaker Bar on Center Nut
Of course, cranking on it makes the wheels try to move, so you can see I’ve got my Mule chocked. But the tires compress and don’t give a firm ‘stop’ to push against.

Any tips? I’ve tried PBlaster and ‘standing on the breaker bar for more force, but no progress so far. Heat? Hammer Drill? Rent a Gorilla?
'58 M274A3 Mule, SN 10965
'62 M422A1 Mighty-Mite, SN 3741
'65 M416-B1 Mighty-Mite Trailer, SN 11
'97 LTT-HC 'Mule Hauler' Trailer, SN "H.A.C.-054"

markrdje
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Re: Brake Repair Question

Post by markrdje » Wed Jul 20, 2022 2:30 pm

Hit it with a hammer in multiply blows
change user name to mark

Chuck W.
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Re: Brake Repair Question

Post by Chuck W. » Wed Jul 20, 2022 4:47 pm

1/2" drive impact wrench. You'll also need a small T-bar puller to get the drive flange off.

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B8B
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Re: Brake Repair Question

Post by B8B » Sun Jul 24, 2022 12:44 pm

Chuck, as usual you're right on the money. I picked up a decent corded impact wrench (after finding short service life with Harbor Freight power tools) and 'Bam', off came the nut!
IMG_5365.JPG
Nut Removed with Impact Wrench

Then, after removing the "Dirt and Liquid Deflector (Item #14 in Chuck's provided diagram), I used a small wheel puller and off came the seal plate and seal parts (Items #15-18):
IMG_5366.JPG
Seal After Removing Dirt and Liquid Deflector

This shot shows the Gasket (Item #19) with the Bearing retainer plate (Item #20) behind it:
IMG_5368.JPG
Gasket After Seal Removal
Now I'm off to get some seal remover spray and gasket scrapers.

Chuck, I DID find goop in the drain hole passage! Who's idea was to plug it?

One more question: In the picture of the seal, notice the red paper-thin gasket on the front side of the seal plate. John's repair kit didn't include it, and I don't see it in the diagram. Is it needed, and if so are they available? I've got the gasket that John sent in the kit (Item #19), but it's much thicker, and goes behind the seal, not in front of it.

As usual, thanks to all for your inputs. I hope this helps others when they get to this repair.

Brian
'58 M274A3 Mule, SN 10965
'62 M422A1 Mighty-Mite, SN 3741
'65 M416-B1 Mighty-Mite Trailer, SN 11
'97 LTT-HC 'Mule Hauler' Trailer, SN "H.A.C.-054"

Chuck W.
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Re: Brake Repair Question

Post by Chuck W. » Sun Jul 24, 2022 3:30 pm

One more question: In the picture of the seal, notice the red paper-thin gasket on the front side of the seal plate. John's repair kit didn't include it, and I don't see it in the diagram. Is it needed, and if so are they available? I've got the gasket that John sent in the kit (Item #19), but it's much thicker, and goes behind the seal, not in front of it.
DON'T put a thick gasket on the front of the seal retainer plate, just a light coat of Form-a-gasket is all you need. A thick gasket in this location can result in improper clearance and can cause the drum to lock up (don't ask!).
Chuck, I DID find goop in the drain hole passage! Who's idea was to plug it?
They all seem to have a glob of silicone in the hole, must be a "Bubba" modification! :lol:

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Re: Brake Repair Question

Post by Chuck W. » Mon Sep 19, 2022 5:34 pm

Well, I finally got Eeyore out after 2-3 years of covid, etc and low and behold, no brakes! Pulled the drum and found the same thing you did, oil soaked brake shoes.
Tear down, clean, replace output seal, reinstall. I just did the brake clean thing on the shoes, stops pretty good now.
Image


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