240Z Rear Drums wont hold adjustment

[Miles]

I replaced all brake parts new about a year ago. I have to readjust the rear shoes about every two weeks. The adjusters on the wheel cylinders rotate freely. I have had this problem with stock Datsun shoes, Carquest shoes and now with shoes from KVR. When adjusted the brakes are good.

 

Any ideas what I should look for?

 

Thanks

 

Miles

[waynekarnes]

when you pull the parking brake on, a lever pushes on the knurled wheel, turning the wheel, shoving the shoes closer to the drum. when it feels tension, the lever should slip by the knurls.

 

when you installed the shoes, you should have tightened the shoes against the drum and adjusted from there. the emergency brake will adjust from there.

 

if you are adjusting every two weeks, there is something wrong.

 

check the shoes, see that they aren't falling apart. even a manual adjustment should last you around 7500 miles.

 

do you have the right wheels on the correct RWC ( rear wheel cylinder ) ?

 

with the drum off, fingers out of the way, car well supported on jack stands, have some one slowly pull the parking brake, see if the lever engages. does it turn the wheel ?? if not figure out why. if so, then check to see if the adjustment wheel is being allowed to go backwards. it should lock in the adjusted position.

 

the RWC should move freely on the backing plate, if not, you will need to remove it ( leave the brake tube connected, knock the locking plates trapping it to the backing plate out, get some high temp grease in there between the RWC and the backing plate... not much as you don't want it getting on your brake shoes. ). not lubing the RWC is the biggest reason that the adjuster doesn't work. the other is, a loose emergency brake cable. the lever doesn't move far enough to engage the knurls on the wheel.

 

me, i have the opposite issue, won't stop adjusting right rear keeps locking up ... at least it was. i got in there, moved a few things. maybe i fixed it. have other issues to deal with and haven't been working on it lately ( project ).

 

pick up a haynes manual, on this issue, it's almost word for word the same as the nissan factory repair manual.

 

also, make sure that you lubed all the parts that the factory says to lube ... very very important that you lube, for that adjuster to work.

 

wayne

[Miles]

Wayne

 

Thanks for the info. I'll check all of this out next week when I have the axels out to replace the u-joints.

 

Miles

[waynekarnes]

Miles ( one of my younger brother's name is Miles ),

 

you are pulling the axle stubs ??? was thinking i might have to do that. got lucky, backing plate got bent and was rubbing the brake drum. thought i had a bad wheel bearing.

 

if you are going to pull the axles ( you mean half shafts or axles ? ), you don't really need em, as the stock 240z rear brakes work fine, the racers use drum brakes, with up graded shoes, but you could, if you wanted, upgrade to rear disc brakes.

 

half shafts ( nissan calls em drive shafts, most other manufactuers call em half shafts ) are between the rear end and the backing plates. axles go through the backing plate and have the studs to hold the wheels on.

 

this is from brokenbolt here at hybrid. he sent me this when i thought i was gonna have to pull my axle.

 

hope i read your post correctly and you can use this info

again, credit Mike aka brokenbolt

 

wayne

 

This is a cut and past from my notes, I've also posted my notes on my cardomain page here:

 

http://www.cardomain.com/memberpage/496289

 

To remove the rear axles take the car to a qualified mechanic with the tools and equipment to do the job right. For the rest of you who want to do this in your garage on the weekend do this.

 

Get your tools together: first get a 36" long 1" I.D. 1 5/16 O.D. sch 40 pipe and then get some flat stock steel 1"X1/2"X36" drill two 12.5mm holes or 1/2" (it doesn't have to be a precision bore) spaced 4 1/2" center to center or 3 1/4". Then buy thread lock, a 3/4" breaker bar and 1 1/16" socket, 1/2" center punch and 40 oz. hand driver. Next a tire bar 21mm or 13/16" and two 14mm combo wrenches. You should have needle nose pliers plus and minus screw sticks and other common tools. Most important, a service manual like Hayes or Chilton for general information.

 

Set the e-brake and jack the car and support it safely then remove the tires. Disengage the e-brake and remove the four half shaft bolts from the hub, removal of the four bolts from the third member is not required but is recommended for ease of accessibility. They are a shoulder bolt 14mm on both ends. Then the axle nut will be visible looking from the third member towards the wheel hub. (It is best to remove the A arm with strut tower and take it to a qualified machinist and have him remove the nut.) Bolt the flat stock to the hub using the wheel huts and brace it against the car or the ground. Put the breaker bar with pipe and socket on the nut. Send the children to the neighbors house, their ears will be the better for it and now rotate the nut, or at least...try. The nut is crimped on so this can be tough sometimes and this is where most possible damage can occur. Once the nut is removed the half shaft flange should slide off, some don't, but don't worry it will. (It is!

better to remove the A arm and strut tower, take it to a qualified machinist and press the axle out.) Chilton recommends using a slide hammer and center hub puller. I use the center punch and place it in the dimple of the shaft and with the hand driver strike the punch with firm square blows. *DO NOT DAMAGE THE THREADS!!!* Glancing blows may cause damage here and a lot of hassle. The axle will take a few good blows but it will start to move. There is a whole pile of goodies to loose like two seals, two bearings and a center spacer inside the hub so be careful and don't loose any of it. Now is a good time to replace bearings and seals with new ones, if you decide not to replace old parts now you may be doing this axle removal thing again in a few months.

 

On reassemble it is best to use new nuts, but if you use the old ones run a die or rethread tool through it, and on the axle shaft can't hurt either. Use the red thread lock on the nut to ensure it doesn't back off and make sure you tighten the hell out of it! I torque on the high side of the recommended 181-239 ft. lb.. (actually I go to 250). First clean the shaft off the car with a good 4 inch hand grinder and a wire wheel or abrasive pad wheel to remove any bad areas on the shaft end. Next get a good rethread tool, M 20 X 1.50. I use one from my Snap-on set that I bought on-line RD-20. Next install the nut over the shaft and turn. I like to use tap-magic to help the tool glide over the threads. Unlike a die the rethread tool or thread restore tool will cram the remaining metal back into shape to help revitalize the old threads. If the metal will not conform back to shape the tool will remove it. A die will cut new threads in any metal that is there, their is a difference!

. This is only a fix to the issue of removing a nut that had not been properly prepared before de-installation. I am the worst person for not preparing the nut before removal.