Drum Brake problem

[Guest DatsuNoob]

Okay, today I went to change my front brake shoes on my 76 620, and was a little irritated with the Autozone guys when I found them to be about an 1 1/4" shorter that the stock ones. I tried anyway to put them on and when I got the springs back on and them situated, they weren't sitting in the proper location on the backing plate. They were cocked to an angle (the outside edge of the shoes were pointed in toward each other instead of being straight on to make proper contact with the drum), didn't clear the springs on the back side, and left the springs pretty slack instead of them being tight with the stock shoes. They were similar in appearance to the stock shoes, but like I said, about an inch and a quarter too short. This isnt my 1st experience with drum brakes either, so they were installed correctly. I was wondering if you guys could tell me if maybe they gave me shoes for the rear drums? Are the rears smaller or the same as the fronts? Not quite sure because I didnt take the rears off. Also my "star" adjuster was pretty much backed all the way in. I assumed they wouldn't turn out that far to accomodate how small of shoes I was given. I didnt mess with it too much, so I just reassembled the stock shoes, repacked my wheel bearings, and drove home. My driver's side was fine, but the pass side was badly worn.

Any input would be greatly appreciated.

[Bleach]

The front and rear brake shoes are the same size and shape. The rear has a bracket for the parking brake cables. That is the only difference.

 

AutoZone gave you the wrong shoes.

[Guest DatsuNoob]

I was given the wrong shoes indeed. Stupid tweaker must have mixed up the numbers(I posted a thread quite a while ago about crappy auto store service, and am never surprised to recieve it). Anyway, I got it right and looked at them before taking them out of the store, since I know what they look like now. I was surprised at how easy they were to change, there's nothing to 'em. You dont even really need the drum brake spring tool I've used in the past on drum brakes. Anyway, I also picked up a set of Gabriel shocks(fronts, mine were shot :eek:) and 3" rear drop blocks to eliminate my rake. I'll get into that this weekend. Still, I thought it was strange how the pass side wore out and the driver's side still look close to brand new. I must either have a bad adjustment on the pass side, or there's air in the lines causing one side to work harder than the other. I'll bleed 'em and get everything worked out after I do my shocks on Sat. I also noticed most of my bushings are cracked and in pretty bad shape. Where would be the best place to get those? Do they sell them in a kit or are there sizes for universal applications?

[kiznook]

whenever possible take the part with you to compare, ESPECIALLY when dealing with places like autozone/CSK/napa

 

Find a good import shop, even if you have to drive across town, you'll find that they stock more/better parts for your application. Maybe I'm just spoiled, as we have one of the best parts guys here in vantucky!

[Guest DatsuNoob]

how bout those bushings?

[Bleach]

I dont' think there are any full kits. You'll have to tackle each bushing individually and you may find certain ones are not available.

 

For the upper bushing on the kingpins, you can use shock obsorber bushings.

Sway bar bushings are generic for small cars/trucks.

 

see if there's any slop in your idler arm. Usually those go out and a new one firms up the steering response a lot.

 

The brakes are manually adjusted so they certainly could have been out of adjustment on one side.

[datzenmike]

Morning Noob. If one side is worn more than the other then it was probably adjusted and doing all the work, or, it was too tight and maybe draging all the time. It's even possible that the E brake isn't releasing all the way on one side too. The rear brakes share the same line, so any air in it would affect both brakes equally.

 

I find a hard packed dirt road that's level and straight and, jam the brakes on at low speed, and check the slide pattern. I try to get them as equal as possible. Don't forget to adjust the E brake and check that nothing is draging. Always use your E brake when parking. This keeps the cables clean and shiny inside and any linkages loose. I've had cars that never have the E brake on and when you finaly use it the cables are so rusty inside that the brakes go on but don't release properly. I've never had a problem with an E brake that is used all the time, ever!

[datzenmike]

Forgot to mention the front brakes. Ideally, they all (front and back), should almost lock up at the same time. You do not want the back to lock before the front or the back end will try to swing around on you. This is particularly bad when going around a curve in the road (or any turn for that matter). A locked tire is the same as skidding on ice.

 

As a rule during breaking, weight is transfered to the front, pressing down on the tires and increasing traction, preventing them from locking. Add to that the weight of the engine. At the same time weight is lifted from the rears, reducing traction and causing them to lock up. Breaking systems are designed with more braking effort sent to the front brakes than the rears to even this out.

 

In my case, I raised my center of gravity and caused extreme weight transfer to the front and rear wheel lock ups. I drove for several years with four or five car lengths ahead of me so I could slow down slowly enough to not lock up the rears. It was embarrassing to slide up to a sudden stop light with the rear wheels screeching. Bertvorgon suggested an adjustable proportioning valve ($50). I got one and installed it and turned down the pressure to the back brakes. WHAT a difference!!!! Now I can stand on the brakes and not worry. On dry pavement I can just get all four wheels to start to screech and leave some rubber. Almost perfect for what I have.

[Bleach]

NOOB! dude, I'm going to Bekah's birthday bash on Monday in Puyallup. I should just bring you those doors. Even if you don't have the cash now I'd rather they go to good use than stay in my yard. I'm packing things up! :)

 

I'm about to have a small but very inexpensive Datsun yard sale. ;)

[Guest DatsuNoob]

Cool! you should ring me up, Mel plans on going too so I'm sure I'll see you there. I'll have some cash, and I'll buy you a drink for hooking me up. (253)359-6540. See you then.

[Fuelrags]

Hey guys, what's the proper adjustment for the front brakes on a 73' 620???

[datzenmike]

Spin the tire by hand and turn the adjuster in till it just rubs. Pump the brakes a few times to center the shoes and check and adjust again if needed. Try to get both sides more or less equal and turning freely.

 

After a few hundred miles, check them again after they have worn themselves against the drums. The 620 has self adjusters that compensate for wear. It is adjusted automatically every time you use the brakes while backing up. On the rear brakes be sure the E brake is adjusted close, but not dragging. Always use your E brake and you will never have a problem with it.

[fiveNdime]

whenever possible take the part with you to compare, ESPECIALLY when dealing with places like autozone/CSK/napa

 

GEE you forgot the most important one.....Costmore ors Costless for you guys who dont get it. The gay thing about this is that my back right rear was locking up on me too early when I was braking today. I just put it back together but found out my slave cylinder was leaking and got on my brake shoes so time for a brake job..Hells yeah I hope I can get it all together for canby, No on second thought I will have it ready come hell or high water.

 

On that brake deal dont forget to lube up the sliders on the bottom. They gum up and may cause the shoes to wear prematurely on one side.

[yello620]

Spin the tire by hand and turn the adjuster in till it just rubs. Pump the brakes a few times to center the shoes and check and adjust again if needed. Try to get both sides more or less equal and turning freely.

 

After a few hundred miles, check them again after they have worn themselves against the drums. The 620 has self adjusters that compensate for wear. It is adjusted automatically every time you use the brakes while backing up. On the rear brakes be sure the E brake is adjusted close, but not dragging. Always use your E brake and you will never have a problem with it.

 

620's DO NOT have self adjusters. It is all manual adjustment.

[datzenmike]

That would explain a lot... Thinking of my '82 axle?