leversole Posted July 2, 2011 Share Posted July 2, 2011 Going to start changing the king pins on my truck this weekend...had a few questions...I have two service manuals and neither one show a schematic or view of S cam style brakes...Are the shoes attached to the backing plate in a similar manner as automotive brakes? That is, springs and clips? Are they bolted?Anyone have any pictures/diagrams of the brake shoes?Do I unbolt the wheel from the drum THEN remove the wheel then the drum, then the brake? Take off the drum and wheeltogether? How much (aprox) do the wheel and drum weigh?Also, I have the oil bath type bearings...are the seals going to be something I can find easily? If I am careful, can I get the hub offwithout damaging them?Are there any other things I should watch for/be aware of? Quote Link to comment Share on other sites More sharing options...
Rob Posted July 2, 2011 Share Posted July 2, 2011 Going to start changing the king pins on my truck this weekend...had a few questions...I have two service manuals and neither one show a schematic or view of S cam style brakes...Are the shoes attached to the backing plate in a similar manner as automotive brakes? That is, springs and clips? Are they bolted?Anyone have any pictures/diagrams of the brake shoes?Do I unbolt the wheel from the drum THEN remove the wheel then the drum, then the brake? Take off the drum and wheeltogether? How much (aprox) do the wheel and drum weigh?Also, I have the oil bath type bearings...are the seals going to be something I can find easily? If I am careful, can I get the hub offwithout damaging them?Are there any other things I should watch for/be aware of?Hi Leslie, this is not too bad of a job but things are heavy. Get yourself a wide saddle floor jack and don't be afraid to use it. You will remove the tire and wheel assembly first of course. Back the "S" cam adjustment off to release any drag of the shoes on the drums or beneath the ridge that is cut into the edge of the drum so you can pull it off. Next remove your center cap to drain the oil from the hub. There are a couple of different style locking mechanisims to front hub retention but they are easy to figger out. Try to keep the drum/hub assembly centered so it doesn't "cock" as this will compromise the inner seal if side load weight is applied. Pull the drum straight off the spindle, (this is heavy with the spoke attached). You will now see a large spring that pulls the top of the brake shoes together against the "S" cam head itself. Remove this spring, then remove the retention plates and clips holding the bottom of the front shoes to the backing plate. You do not need to remove the shoes or the last step if you want to remove the backing plate and shoes as a unit. These have bolts that run through the backing plate and spindle hub. Remove these and the air line connecting the brake cannister and the assembly will lift off the axle. Most B models had a bolt and washer in the end of the "S" cam and some spacers to center the slack adjuster. Remove these items and the cam itself will push out the bushings in the carrier. Some help with a dead blow hammer may be needed to get the cam broke free from it's slack but not always.If the sealing ring that is part of the spindle has a groove cut into it and you want to replace, it will be expensive. There is no "speedi sleeve" type repair that I've found. You have to replace that ring and it will surprise you as to cost. The king pins are pretty straightforward if you've ever done a set before. Take the retainers loose in the top, and push the pin out the bottom of the axle/spindle assembly.Good luck, I thought I had photos of when I took mine apart but must be on another computer.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
mowerman Posted July 2, 2011 Share Posted July 2, 2011 Hi Leslie, this is not too bad of a job but things are heavy. Get yourself a wide saddle floor jack and don't be afraid to use it. You will remove the tire and wheel assembly first of course. Back the "S" cam adjustment off to release any drag of the shoes on the drums or beneath the ridge that is cut into the edge of the drum so you can pull it off. Next remove your center cap to drain the oil from the hub. There are a couple of different style locking mechanisims to front hub retention but they are easy to figger out. Try to keep the drum/hub assembly centered so it doesn't "cock" as this will compromise the inner seal if side load weight is applied. Pull the drum straight off the spindle, (this is heavy with the spoke attached). You will now see a large spring that pulls the top of the brake shoes together against the "S" cam head itself. Remove this spring, then remove the retention plates and clips holding the bottom of the front shoes to the backing plate. You do not need to remove the shoes or the last step if you want to remove the backing plate and shoes as a unit. These have bolts that run through the backing plate and spindle hub. Remove these and the air line connecting the brake cannister and the assembly will lift off the axle. Most B models had a bolt and washer in the end of the "S" cam and some spacers to center the slack adjuster. Remove these items and the cam itself will push out the bushings in the carrier. Some help with a dead blow hammer may be needed to get the cam broke free from it's slack but not always.If the sealing ring that is part of the spindle has a groove cut into it and you want to replace, it will be expensive. There is no "speedi sleeve" type repair that I've found. You have to replace that ring and it will surprise you as to cost. The king pins are pretty straightforward if you've ever done a set before. Take the retainers loose in the top, and push the pin out the bottom of the axle/spindle assembly.Good luck, I thought I had photos of when I took mine apart but must be on another computer.Robthe big shops generally use a big type special jack for tire,and hub removal,,but you can put a board slide it under tire and put abuncha grease on the board then raise the truck just so you can just barely turn the tire on the board then have a guy give you a hand pulling the whole thing straight off the spindle sliding it easy on the greased board,,,just a little helpful hint,works like a charm if you do it rite,,also put a little grease.on bottom of tire.good luck,bob,oh have that other guy bring beer,lol. Quote Link to comment Share on other sites More sharing options...
Rob Posted July 2, 2011 Share Posted July 2, 2011 the big shops generally use a big type special jack for tire,and hub removal,,but you can put a board slide it under tire and put abuncha grease on the board then raise the truck just so you can just barely turn the tire on the board then have a guy give you a hand pulling the whole thing straight off the spindle sliding it easy on the greased board,,,just a little helpful hint,works like a charm if you do it rite,,also put a little grease.on bottom of tire.good luck,bob,oh have that other guy bring beer,lol. Yup. That's why I purchased a "Back Buddy" by OTC tools. This works slick and supports the weight easily. Keeps trips to the chiropractor down to a minimum too.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
mowerman Posted July 2, 2011 Share Posted July 2, 2011 Yup. That's why I purchased a "Back Buddy" by OTC tools. This works slick and supports the weight easily. Keeps trips to the chiropractor down to a minimum too.Roboh ya,,those things are godsent,,but ofcoarse not everyone owns them..i have a motorcycle jack,for harley,,was just wondering if i could use that,,,you know i bet i could...bob Quote Link to comment Share on other sites More sharing options...
leversole Posted July 2, 2011 Author Share Posted July 2, 2011 Thanks for the information...this outghta get me going!Wow! THey are proud of those back buddy's ($1300)I believe I can make an adapter for my MC jack that will work...My plan is to take the time to blast and paint all of the parts including the wheels...I'll take plenty of pics...Thanks Again... Quote Link to comment Share on other sites More sharing options...
mowerman Posted July 2, 2011 Share Posted July 2, 2011 Thanks for the information...this outghta get me going!Wow! THey are proud of those back buddy's ($1300)I believe I can make an adapter for my MC jack that will work...My plan is to take the time to blast and paint all of the parts including the wheels...I'll take plenty of pics...Thanks Again...ya,,,thats a good idea,,im planning on doing the same thing,,but also putting brand new tires all around,also,i better plan on spending a couple a G,s,lol...good luck,bob Quote Link to comment Share on other sites More sharing options...
Rob Posted July 2, 2011 Share Posted July 2, 2011 ya,,,thats a good idea,,im planning on doing the same thing,,but also putting brand new tires all around,also,i better plan on spending a couple a G,s,lol...good luck,bobThink I gave $250 for my "Back Buddy" from a retiring mechanic. You are correct in OTC being "proud" of their tools. The front casters were shot but that is about the only thing I've done to it. I did get the arms for all the different hub styles so didn't need to fabricate any adapters with this thing. Mine is the original and the current model is "Back Buddy II". I this one better cause it uses a hand wheel for elevation as opposed to a crank. It is smoother in operation also.With a hydraulic motorcycle jack I'm sure it would be easy to make a top plate with arms to bolt to a specific hub and it would be good for a single purpose. I like this thing cause atter the hub is removed, it can be laid it on it's back and the inner seal is facing straight up and very east to get to. For years I used a wide saddle floor jack for this job but as I get older, fatter, much lazier, and increasingly hunchback, I look for an easy way out to things.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
3rdWrightBrother Posted July 3, 2011 Share Posted July 3, 2011 ya,,,thats a good idea,,im planning on doing the same thing,,but also putting brand new tires all around,also,i better plan on spending a couple a G,s,lol...good luck,bobBob- If you ever need an extra pair of hands just let me know- been a lot of years since I had a chance to touch an old Mack- I think I miss it Russ Quote Link to comment Share on other sites More sharing options...
mowerman Posted July 3, 2011 Share Posted July 3, 2011 Think I gave $250 for my "Back Buddy" from a retiring mechanic. You are correct in OTC being "proud" of their tools. The front casters were shot but that is about the only thing I've done to it. I did get the arms for all the different hub styles so didn't need to fabricate any adapters with this thing. Mine is the original and the current model is "Back Buddy II". I this one better cause it uses a hand wheel for elevation as opposed to a crank. It is smoother in operation also.With a hydraulic motorcycle jack I'm sure it would be easy to make a top plate with arms to bolt to a specific hub and it would be good for a single purpose. I like this thing cause atter the hub is removed, it can be laid it on it's back and the inner seal is facing straight up and very east to get to. For years I used a wide saddle floor jack for this job but as I get older, fatter, much lazier, and increasingly hunchback, I look for an easy way out to things.Robbeen busy all day doing a few last minute chores around here,,will be getting back surgury,tuesday,,and wont be able to scratch my ass,for next few weeks,,getting back to the equipment..lets face it,,rob,,everything on these things are friggen heavy,,anymore i try to use,fork lift,cherry pickers,for lifting anything,,i have access to both,,makes life easy,,what does your back buddy look like,,that was a hell of a price,,who cares about the casters.lol...bob Quote Link to comment Share on other sites More sharing options...
mowerman Posted July 3, 2011 Share Posted July 3, 2011 Bob- If you ever need an extra pair of hands just let me know- been a lot of years since I had a chance to touch an old Mack- I think I miss it Russahrite,man appreciate the offer,,ill be working on that truck,,hopefully pretty heavy in about a year or so,,deponds on a couple loose ends i need to get tied up,may have a lot more cash flow,in a few months,,thanks russ Quote Link to comment Share on other sites More sharing options...
Rob Posted July 3, 2011 Share Posted July 3, 2011 been busy all day doing a few last minute chores around here,,will be getting back surgury,tuesday,,and wont be able to scratch my ass,for next few weeks,,getting back to the equipment..lets face it,,rob,,everything on these things are friggen heavy,,anymore i try to use,fork lift,cherry pickers,for lifting anything,,i have access to both,,makes life easy,,what does your back buddy look like,,that was a hell of a price,,who cares about the casters.lol...bobI could only find a photo of the Back Buddy II on the net. Mine looks very similar except the ratcheting handle is a handwheel with a gear reducer for elevation. I also have all that adapters for inboard, and outboard drums for both Dayton, and Budd style. It is pretty slick cause the drum will pull right off with very little resistance and installs just as easily without any damage, or smashed fingers.http://www.tsissg.com/aitdownloadablefiles/download/aitfile/aitfile_id/61/I have yet to purchase a forklift but that is on the list. Now that I'm working alone it is easy to rely on machines to do the heavy work. I have a skid loader and forks which gets a lot of use but at times a forklift is more handy. Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
mowerman Posted July 3, 2011 Share Posted July 3, 2011 I could only find a photo of the Back Buddy II on the net. Mine looks very similar except the ratcheting handle is a handwheel with a gear reducer for elevation. I also have all that adapters for inboard, and outboard drums for both Dayton, and Budd style. It is pretty slick cause the drum will pull right off with very little resistance and installs just as easily without any damage, or smashed fingers.http://www.tsissg.com/aitdownloadablefiles/download/aitfile/aitfile_id/61/I have yet to purchase a forklift but that is on the list. Now that I'm working alone it is easy to rely on machines to do the heavy work. I have a skid loader and forks which gets a lot of use but at times a forklift is more handy. Roboh,,ok,i wasnt aware the buddy was so flexable,now i understand why there so spendy..ya my neighbor has two big yale lifts,for loading flatbeds,i can use anytime,and a couple engine cranes,,next time i take heads off,i will use the engine houst,,when i put up my shop i will install i beams overhead for chain fall,,,lol,,,no more manual labor for this kid,,used to man handle mack heads in my 20,s no more,,,ya hear me?,,,save all that man handle for unwanted chores.lol...bob Quote Link to comment Share on other sites More sharing options...
Rob Posted July 3, 2011 Share Posted July 3, 2011 oh,,ok,i wasnt aware the buddy was so flexable,now i understand why there so spendy..ya my neighbor has two big yale lifts,for loading flatbeds,i can use anytime,and a couple engine cranes,,next time i take heads off,i will use the engine houst,,when i put up my shop i will install i beams overhead for chain fall,,,lol,,,no more manual labor for this kid,,used to man handle mack heads in my 20,s no more,,,ya hear me?,,,save all that man handle for unwanted chores.lol...bobYeah, if you are going to do this kind of work with any type of frequency it is worth the cost to have good equipment. I've never pulled a set of Mack heads without an engine crane. I now have an 18' wide three ton gantry crane I use a lot and the engine crane, (cherry picker) seldom even comes out of the corner. I have a jig that bolts both heads together by the ports and they remove as an assembly. Pretty quick that way. Also got real tired of rolling under cars on a creeper all the time so put two 9000# surface mount lifts in the shop.Hell I'm so lazy in my old age I even got tired of working the handle on a chassis lube gun so I purchased a pneumatic drum type. Then got tired of pouring oil out of quart, and gallon containers, so purchased reels, pumps, and tanks. And so the story continues........Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
fxfymn Posted July 3, 2011 Share Posted July 3, 2011 Hell I'm so lazy in my old age I even got tired of working the handle on a chassis lube gun so I purchased a pneumatic drum type. Then got tired of pouring oil out of quart, and gallon containers, so purchased reels, pumps, and tanks. And so the story continues........Money well spent compared to putting off the required service because it's such a PIA to do with jugs etc. When I pulled the wheels on the 52 I made up a wheel lift by modifying my pallet forks to fit on the 3PH of my small tractor. The tractor is small enough to get around inside the garage and it makes lifting the wheel assemblies a breeze. Think creatively and you'll figure out a solution.As to the seals: If you go through all the work of pulling everything replace them. They are rubber and do not last forever, so even if they are good now they will need replacement long before you wear out brakes on a show truck. And is it worth doing it all again if the old seals leak when you get it back together? 1 Quote Money, sex, and fire; everybody thinks everyone else is getting more than they are! Link to comment Share on other sites More sharing options...
rhasler Posted July 3, 2011 Share Posted July 3, 2011 As to the seals: If you go through all the work of pulling everything replace them. They are rubber and do not last forever, so even if they are good now they will need replacement long before you wear out brakes on a show truck. And is it worth doing it all again if the old seals leak when you get it back together?My sentiments exactly. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
mowerman Posted July 3, 2011 Share Posted July 3, 2011 Yeah, if you are going to do this kind of work with any type of frequency it is worth the cost to have good equipment. I've never pulled a set of Mack heads without an engine crane. I now have an 18' wide three ton gantry crane I use a lot and the engine crane, (cherry picker) seldom even comes out of the corner. I have a jig that bolts both heads together by the ports and they remove as an assembly. Pretty quick that way. Also got real tired of rolling under cars on a creeper all the time so put two 9000# surface mount lifts in the shop.Hell I'm so lazy in my old age I even got tired of working the handle on a chassis lube gun so I purchased a pneumatic drum type. Then got tired of pouring oil out of quart, and gallon containers, so purchased reels, pumps, and tanks. And so the story continues........Robya copy all that,,,we have those air oil hoses,at work,boy those things are the cats ass,,especially middle of winter,when real thick,,if you have never done heads by hand,,let me tell you,,,your not missing anything,,,gotta run babba,breakfast,and,more yard work,woohoo just what i prayed for,,lol...bob Quote Link to comment Share on other sites More sharing options...
41chevy Posted July 4, 2011 Share Posted July 4, 2011 I always did all the heavy work alone and in my early days with out a lot of good equipment or sense. Guess thats why I'm blessed with bad knees, bad back and shoulder problems. Now I buy or build anything to make my work easier. My shop is a 50 x50 steel building with 16 to 25 foot peaked roof. I don't have a lot of extra space with my machine shop tools for more than one total disassembly (my AC),one inside storage (my B /Challenger mixer) and one for repairs of our vehicles. So I purchased an electric fork lift from a warehouse that was folding up. It's a bit smaller than what you see inside say a Lowes or Home Depot i consider it a truck loader. I can lift or move pretty much anything in the shop I need to. It don't fill the shop up with exhaust if its and extended job and best of all it fits in a 5 x 5 space. I used it to move around and hang the disassembled AC chassis and transaxle. I watched the auctioneer site for factory or warehouse auctions, but I guess they can be found on Craigs list of an equipment dealer. batteries I bought 4 deepcycle marine batteries, the lift has a 115 volt charger that will bring the batteries from 2/3 ischarge to full in 10 hours. Not an out door rough road unit but works for me. Its a Hyster e25xm I paid $1250 for it. rated for 2500 lb lift Paul Quote "OPERTUNITY IS MISSED BY MOST PEOPLE BECAUSE IT IS DRESSED IN OVERALLS AND LOOKS LIKE WORK" Thomas Edison “Life’s journey is not to arrive at the grave safely, in a well preserved body, but rather to skid in sideways, totally worn out, shouting ‘Holy shit, what a ride!’” P.T.CHESHIRE Link to comment Share on other sites More sharing options...
cgallamore Posted July 4, 2011 Share Posted July 4, 2011 the big shops generally use a big type special jack for tire,and hub removal,,but you can put a board slide it under tire and put abuncha grease on the board then raise the truck just so you can just barely turn the tire on the board then have a guy give you a hand pulling the whole thing straight off the spindle sliding it easy on the greased board,,,just a little helpful hint,works like a charm if you do it rite,,also put a little grease.on bottom of tire.good luck,bob,oh have that other guy bring beer,lol. [/quoteold street sign works even better..... Quote http://www.bigmacktrucks.com/uploads/1272400769/gallery_4852_794_314995.jpg Link to comment Share on other sites More sharing options...
Rob Posted July 4, 2011 Share Posted July 4, 2011 If the sealing ring that is part of the spindle has a groove cut into it and you want to replace, it will be expensive. There is no "speedi sleeve" type repair that I've found. You have to replace that ring and it will surprise you as to cost. RobThe front "Stemco" hub seals were $142.24 each side on my truck with a FA-517 steer axle. This was the seal, and the wear ring which had a groove cut into it from use. It did not however leak oil. The FA-505 uses the same seal. If you go to packing the hub bearings with grease, you can get by at less expense.Rob Quote Plodding along with no job nor practical application for my existence, but still trying to fix what's broke. Link to comment Share on other sites More sharing options...
leversole Posted July 4, 2011 Author Share Posted July 4, 2011 The front "Stemco" hub seals were $142.24 each side on my truck with a FA-517 steer axle. This was the seal, and the wear ring which had a groove cut into it from use. It did not however leak oil. The FA-505 uses the same seal. If you go to packing the hub bearings with grease, you can get by at less expense.RobGot lucky on the left side...the wear ring is smooth and shiny...bearings look and feel good also...Only problems so far (I havent got the backing plate off yet!) the rear brake shoe is frozen to the adjuster and hasn't moved in a while (the front brakes were disconnected when I got the truck, first thing I did was hook them) Quote Link to comment Share on other sites More sharing options...
mowerman Posted July 4, 2011 Share Posted July 4, 2011 I always did all the heavy work alone and in my early days with out a lot of good equipment or sense. Guess thats why I'm blessed with bad knees, bad back and shoulder problems. Now I buy or build anything to make my work easier. My shop is a 50 x50 steel building with 16 to 25 foot peaked roof. I don't have a lot of extra space with my machine shop tools for more than one total disassembly (my AC),one inside storage (my B /Challenger mixer) and one for repairs of our vehicles. So I purchased an electric fork lift from a warehouse that was folding up. It's a bit smaller than what you see inside say a Lowes or Home Depot i consider it a truck loader. I can lift or move pretty much anything in the shop I need to. It don't fill the shop up with exhaust if its and extended job and best of all it fits in a 5 x 5 space. I used it to move around and hang the disassembled AC chassis and transaxle. I watched the auctioneer site for factory or warehouse auctions, but I guess they can be found on Craigs list of an equipment dealer. batteries I bought 4 deepcycle marine batteries, the lift has a 115 volt charger that will bring the batteries from 2/3 ischarge to full in 10 hours. Not an out door rough road unit but works for me. Its a Hyster e25xm I paid $1250 for it. rated for 2500 lb lift Paulsound perfect,man,,had not seen one in years...all ours at work are propane..bob Quote Link to comment Share on other sites More sharing options...
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