Avanti Rear Brakes

[wagone]

This question should (or could) be titled "Primary Shoe/Secondary Shoe?" or "Choose Your Mechanic Carefully". I've just today removed my Avanti's rear drums and hubs (not as difficult as I had assumed). What greeted me came as a little bit of a surprise. The pictures in the Avanti Shop Manual under the brake section are not very good or clear. The photo in the section on the rear axle assembly is better. This photo shows the front shoe (which I've always believed to be the primary shoe) to be larger than its neighbor to the rear of the axle--larger in length of lining. This is the first time these drums have been off the axle since I bought the car and my shoes are installed the reverse of the photo--that is the larger shoe is to the rear of the axle on both sides of the car. Could this be correct and the manual wrong or was the "mechanic" who last did brake work a little less than 100 percent efficient on that day? The shoes have a considerable amount of lining left. Any problem envisioned with putting them back the correct way (as per the photo in the manual)? Also the drums measure about .330-.340" thick. The shop manual under specifications in the front appears to state that minimum thickness is .180" The brake section says that the diameter of the drum can only be increased .060" to clean up or true up. So what is the minimum thickness acceptable of these drums? Or is the maximum diameter not to exceed 11.060"? My drums are not scored and I intend to have them checked for roundness and or taper--so they MAY not need any turning. Guidance, please. And remember, choose your mechanic carefully or do the work yourself. (When I rebuilt the front brakes I found the pipe connecting the two halves of the caliper to be routed up the outside of the caliper instead of the inside as specifically stated in the shop manual). I hope to take this car (safely) to Omaha.

wagone and the R2 Avanti

[N8N]

I thought that the front shoe was always shorter. As for the "thickness" I would assume that that refers to the rotors, although .180" sounds a little thin, it's been years since I worked on a car with non-vented rotors so I don't have a frame of reference. The magic number on the rears is the 11.060" for the inside diameter of the drum, if larger than that you will fail a safety inspection. I think the wear limit is actually higher than that but .060" is the max for turning, so if yours are over that but still usable you may need to take the shop manual with you to the inspection station to document the wear limit (assuming you have inspection in your state)

good luck

nate

--
55 Commander Starlight

http://home.comcast.net/~njnagel

[wagone]

Thanks Nate. I may not be able to tell from the photo in the shop manual whether what is pictured is the left or right side brake and I haven't done any drum brake work in years. So you are saying that they are installed correctly and the primary shoe is behind the axle? As for the .180" thickness the spec page of the shop manual says .180" for the rear drum and .416" for the disc minimum thickness (funny thing though the brake section states the minimum thickness as .330" for the disc! So it is just possible I suppose that the .180" for the rear is wrong and it should be .416"--but that would be stretching credibility). Anyway I don't need the definitive answer for a few days as I'm going to do bearing and or axle work also. But I'll be checking here for additional replys.

wagone

[StudeRich]

Wagone; Nate is correct for the standard drum brake and most any make and model EXCEPT a Disc. brake equipped Stude. the manual is correct they go backwards, short shoe aft. long shoe forward. These are not Bendix type, but Wagner Lockheed type brakes![^]

StudeRich
Studebakers Northwest
Ferndale, WA

[wagone]

So.........StudeRich, if I read correctly, what you are saying is my shoes are installed backwards and the mechanic who did this was merely adhering to "conventional" practice and not realizing that Studebaker did things backwards. If I'm not careful this could get confusing and I'm not looking at the car now but only at the photo in the shop manual and I must admit I can't tell from the photo which side of the car was used for the shoot. But the larger shoe on my car is definitely behind the axle. The pictures in the brake section, as mentioned earlier, are not conclusive and now I'm wondering about the photo in the axle section as you really can't tell which side of the car is shown--although I still want to say it is left side and if so the larger shoe is ahead of the axle and this is not the way mine is. It must be left side because the parking brake lever goes behind the axle and in the photo the lever is to the right side of axle. And if it is left side it shows the smaller shoe to the rear--which is not the way my car is set up.

wagone

[StudeRich]

ARE YOU SURPRIZED, Wagone, you went to a non-Stude. guy, with a 1963 car and this is 2006!LOL

StudeRich
Studebakers Northwest
Ferndale, WA

[Jackson]

I have just finished a complete rebuild of the power disc brake system on my 63 Lark R2, including conversion to a dual system. When I removed the rear drums I saw that the front (primary) was the larger shoe, as shown in the shop manual photo. The parking brake cable was attached to the smaller rear (secondary) shoe. Since I have always installed shoes with the "big in back" I did some internet research on brake shoe installation. In all the articles that mentioned shoe size the smaller shoe was identified as the primary shoe, regardless of manufacturer. Since I could not find a written reference about primary/secondary shoe size anywhere in the manual I installed the relined shoes as I always have "big in back".

[Dwain G.]

Actually the manual pictures are very definite if you know what to look for. Notice where the hand brake cable enters the backing plate, and notice which shoe the actuating lever is attached to. Figure 12 in the Brake section is showing the right rear, and Figure 5 in the Rear Axle section is showing the left side.
Too bad they didn't explain shoe installation in the text. I do have a Raybestos service manual that shows this brake with the forward shoe having the longer lining. The description of this brake begins "This brake was designed for use on rear wheels in conjunction with disc brakes on the front wheels".

quote:
I can't tell from the photo which side of the car was used for the shoot. But the larger shoe on my car is definitely behind the axle. The pictures in the brake section, as mentioned earlier, are not conclusive and now I'm wondering about the photo in the axle section as you really can't tell which side of the car is shown--wagone

Dwain G.