Dumb Question Needs Smart Answer...

[Big Blzn]

O.K. I need two noob questions answered please.

First. How do I adjust the drums on my 12bolt so the ebrake is tightened up so it actually works? How do I know how much to tighten when figured out?

Second. I am going to be replacing my body mounts on my K5 and was inspecting everything before I get started in several weeks and can't figure out what I need to remove to get to the radiator support bolt for the body mounts. I'm sure if I tore everything off the front I would see it easily but wanted to do as little tearing apart as possible. I can't even see the head of the existing bolt. Pics would be cool if readily available too.

Thanks fellas
Hoby

 

[dremu]

The brake thing, I hate to say it, is answered by "Buy a Chilton's." Best $15 or so you'll spend (less if you buy used on, say, Ebay.)

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=CHI&MfrPartNumber=28140&PartType=626&PTSet=A

Ouch, Kragen/Checker/Schucks gets $20. If you're patient, Ebay is better:

http://cgi.ebay.com/ebaymotors/Chil...009QQitemZ190154465451QQrdZ1QQsspagenameZWD1V

For example. There are a bazillion copies in varying condition listed. Also try your local used bookstore.

ANYWAY ... to answer your question:

First, lube the hell out of the star adjuster, like soak it in WD40 or penetrating oil or the like. They seize up, even in non-rust country like you and I have, and then they fail to self-adjust.

Then you pry up the snap that holds the star -- in operation it can only turn one way, right -- so that it can turn the other way. One side of the truck turns clockwise and the other anti-clockwise, IIRC, so watch that. The snap is spring-loaded, so it'll pop back into place when you get the screwdriver out of the way.

Then turn the adjuster so that it expands the drums. I've heard that somehow you can do this with the drum still on, but I've never figgered out how. I do it with the drum off, then test-fit the drum... keep expanding the adjuster until the drum baaaarely drags on the shoes, like it'll spin but you can feel the drag. (Face it, if you adjust it any more you'll just be wearing your shoe lining off for the next few miles!) This way you get your exercise lifting the drum, and since you have a 12b you can be thankful it's not a dually 14BFF -- those drums are MONSTROUS.

BTW, the books say you can also adjust the rear brakes -- if the adjuster isn't seized, see above! -- by backing up at a fair clip and banging the brakes, two or three times. Depending on your parking situation, coming out of the driveway may just suffice. I think this is how the adjusters are alleged to self adjust, but I, as you may notice, don't trust them to.
Okay, with the allegedly-but-never-actually-working-self-adjusters now adjusted manually , you can do the parking brake cable. Ideally you set it so that it self-stops, i.e. the shoes are pulled tight against the drums, right about the bottom of the pedal travel (which is, err, five or six clicks maybe?) This way you know when you let the pedal up again the shoes are nice and loose, or at least as loose as the adjusters will let them be. The cable arrangement for the 80's trucks is weird, but I imagine your '72 is like my '74's, and you just turn the nut on the threaded rod coming off the cable from the pedal. Be sure the cables aren't frayed along their path, and maybe lube them where they go into the sheaths back at the axle end (some nice white lithium or moly grease would prolly make them happy.)
I categorically deny EVER driving three miles to the parts store, wondering what that burning smell was, with the parking brake set.

Body mounts, duh, I've never done, so I have no advice for you there.

-- A

 

[bp71k5]

I can help with the body mount.

the head on the front bolts locks into a metal hole preventing it from turning. (It's a carriage bolt) So all you need to do it remove the nut from the bottom. Probably the easiest one to do unless the bolt is rusted to the nut.

Unless yours are in good shape, plan on replacing them since they rust pretty easily. half of mine broke trying to remove the nuts. If you're really into rust prevention, they make stainless replacement versions you can get at LMC.

 

[Big Blzn]

The brake thing, I hate to say it, is answered by "Buy a Chilton's." Best $15 or so you'll spend (less if you buy used on, say, Ebay.)

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=CHI&MfrPartNumber=28140&PartType=626&PTSet=A

Ouch, Kragen/Checker/Schucks gets $20. If you're patient, Ebay is better:

http://cgi.ebay.com/ebaymotors/Chil...009QQitemZ190154465451QQrdZ1QQsspagenameZWD1V

For example. There are a bazillion copies in varying condition listed. Also try your local used bookstore.

ANYWAY ... to answer your question:

First, lube the hell out of the star adjuster, like soak it in WD40 or penetrating oil or the like. They seize up, even in non-rust country like you and I have, and then they fail to self-adjust.

Then you pry up the snap that holds the star -- in operation it can only turn one way, right -- so that it can turn the other way. One side of the truck turns clockwise and the other anti-clockwise, IIRC, so watch that. The snap is spring-loaded, so it'll pop back into place when you get the screwdriver out of the way.

Then turn the adjuster so that it expands the drums. I've heard that somehow you can do this with the drum still on, but I've never figgered out how. I do it with the drum off, then test-fit the drum... keep expanding the adjuster until the drum baaaarely drags on the shoes, like it'll spin but you can feel the drag. (Face it, if you adjust it any more you'll just be wearing your shoe lining off for the next few miles!) This way you get your exercise lifting the drum, and since you have a 12b you can be thankful it's not a dually 14BFF -- those drums are MONSTROUS.

BTW, the books say you can also adjust the rear brakes -- if the adjuster isn't seized, see above! -- by backing up at a fair clip and banging the brakes, two or three times. Depending on your parking situation, coming out of the driveway may just suffice. I think this is how the adjusters are alleged to self adjust, but I, as you may notice, don't trust them to.
Okay, with the allegedly-but-never-actually-working-self-adjusters now adjusted manually , you can do the parking brake cable. Ideally you set it so that it self-stops, i.e. the shoes are pulled tight against the drums, right about the bottom of the pedal travel (which is, err, five or six clicks maybe?) This way you know when you let the pedal up again the shoes are nice and loose, or at least as loose as the adjusters will let them be. The cable arrangement for the 80's trucks is weird, but I imagine your '72 is like my '74's, and you just turn the nut on the threaded rod coming off the cable from the pedal. Be sure the cables aren't frayed along their path, and maybe lube them where they go into the sheaths back at the axle end (some nice white lithium or moly grease would prolly make them happy.)
I categorically deny EVER driving three miles to the parts store, wondering what that burning smell was, with the parking brake set.

Body mounts, duh, I've never done, so I have no advice for you there.

-- A

OK, that is what I thoought because I have read that before and it is the same procedure as the 14bff I have in the garage but when I looked at the 12blot at night it I couldn't find the little spring loaded cap. I saw what looked like factory indentations like on the 14blot but didn't look like a cap was made to be there. I'll look closer now that it's daylight. Thanks for the info. If I don't see anything then I'll take the drums off and peek inside.

I can help with the body mount.

the head on the front bolts locks into a metal hole preventing it from turning. (It's a carriage bolt) So all you need to do it remove the nut from the bottom. Probably the easiest one to do unless the bolt is rusted to the nut.

Unless yours are in good shape, plan on replacing them since they rust pretty easily. half of mine broke trying to remove the nuts. If you're really into rust prevention, they make stainless replacement versions you can get at LMC.

So when I get the nut off the front bolt the carriage bolt should just pop up with the hit of a hammer and I'll see it? Let's see what happens.

Thanks again fellas
Hoby

 

[blazin_blazer]

the little metal ''bar'' that only allows the adjuster nut to turn 1 way....

well i've been told its actually made to turn the adjuster .....if its all working right..., but was told that you had to be driving backwards and pump brakes and that thingy will turn adjuster a click at a time and tighten brakes up...it will do it driving backwards and pumping brakes i tightened mine up so tight the truck wouldn't pull the brakes before(was like emergency brake was set)...had to use a spoon and loosen it up!
anyone else every heard of this?

 

[Big Blzn]

Well, here's what I played with today on the ebrake. My 12bolt doesn't have the adjuster thing that I can access from the outside part of the backing plate. It is just not there. Since I was too lazy to take the tires off I found where the ebarke makes a big loop from the rear wheels and where it is connected to the cable from the ebrake pedal is a threaded rod that connects the two cables and the rod has a double nut on it. So all I did was just tighten the nut about five turns and it seemed to make the ebrake pedal firmer but didn't do a whole lot for the actual "stopping" of the blazer. Maybe I need to check the pads for wear.

 

[dremu]

Well, here's what I played with today on the ebrake. My 12bolt doesn't have the adjuster thing that I can access from the outside part of the backing plate. It is just not there. Since I was too lazy to take the tires off I found where the ebarke makes a big loop from the rear wheels and where it is connected to the cable from the ebrake pedal is a threaded rod that connects the two cables and the rod has a double nut on it. So all I did was just tighten the nut about five turns and it seemed to make the ebrake pedal firmer but didn't do a whole lot for the actual "stopping" of the blazer. Maybe I need to check the pads for wear.

Yep, that's the parking brake adjustment I talked about.

Karnak The Invincible says you need to take those drums off and look at the adjusters.

['Sides, it's EASY on a semifloat like that... jack the truck up, take off the wheel, and the drum just slides off, not like the 14BFF's.]

-- A

 

[Colotow]

couple small points

IF your drums are worn, you might need to try and adjust your rear shoes in to allow then to clear the lip from the wear.

you can usually poke a small (like a pocket one) screwdriver in, and gently push the little arm back, makes it easier to turn the adjuster

i used to use antisieze on the threads of the adjusters, then i found a spray graphite lube, goes on like spray paint, dries on. brake dust won't stick, and it lasts for along time. take them apart, clean, wire brush, then spray the threads and inside the little end caps, let dry and you're good.

i had to bush the threaded rod on the front cable with some washers to get it adjusted after an axle swap, just took off the nut, stacked an inch or so, and back together. cable was fine, just too long.