rear brake springs

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Cahhh68
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rear brake springs

Post by Cahhh68 »

Been 17 years since I did rear brake overhaul. Before taking the shoes off the backing plate to get to the cylinders, the springs were behind or under the shoes - between the shoes and the backing plate but hooked on the ends to the proper holes in the shoes. Looking at the drawing of the rear brake assembly on the tech wiki, it shows the springs are on the outside of the shoes - on the brake drum face side of the shoes. Which location is correct for the springs?
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tjp
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Re: rear brake springs

Post by tjp »

The go behind the shoes so the shoes stay in place. Otherwise they won't stay in place while you try to put the drum on.
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Cahhh68
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Re: rear brake springs

Post by Cahhh68 »

Thank you. That is good to know as I've never had problems with the springs being behind the shoes. And the steel curved bases of the shoes are touching the backing plate, which I believe they are supposed to. The problem I have is the part of the safety brake lever that extends through the square hole in the brake shoe is not extending far enough. I have followed the plan and placement of shims and find it impossible to get them all back in even when greased. Even just putting one of the two on the back side of the plate is very difficult. And with both shims correctly installed on the shoe side of the plate, the body of the cylinder stands off of the plate enough that the safety brake lever does not extend well into the square hole on the shoe. I put them back together 17 years ago and thought they were working as designed but I am thinking the shoes were not moving as designed per the sliding wheel cylinder is supposed to do because I did not grease the shims back then but forced them in so tight that they probably could not move. I was not aware at that time they were meant to slide. What am I missing? Why is the safety brake lever not extending into the hole?
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Re: rear brake springs

Post by zippy67roadster »

The springs go in the front of the shoes like the drawing in the Tech wiki. The drums should go on with no issues, if they don't you need to use the adjuster to get the drums to fit. There should be just a slight bit of drag when adjusted properly. As for your parking brake issue I am not sure why the rod is not extending into the opening enough to attach it. I would need pictures to try and solve it for you. I always put the parking brake rod on the wheel cylinder before putting the wheel cylinder on with the shims. Have you tried that?
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Cahhh68
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Re: rear brake springs

Post by Cahhh68 »

Yes, the safety brake lever is inserted through the backing plate as the wheel cylinder is put in place. The coupler that is part of the lever is not fitting snugly in the receptor boss on the end of the wheel cylinder because the wheel cylinder body is standing off of the plate a bit too much on the end where the coupler fits into the cylinder body. But it would seem if the "catcher" part of the lever was away from the backing plate (on the shoe side) that it would catch the brake shoe as the shoes are snug against the backing plate. It is an aftermarket wheel cylinder but I lined it up with the original factory one and all dimensions are the same. But maybe I did not check the lever dimension where it catches the shoe. I'll look at it again and can use the original lever if the after market one is short. To me it seems the shims are holding the cylinder out but they are flat, engaged, and in the correct slot on the wheel cylinder. I'll try to send a photo on a later post. Thank you for your response.
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Re: wheel cylinder fitment

Post by Cahhh68 »

Having watched a very helpful video, I learned that only 3 of 4 supplied shims are used with each rear wheel cylinder and that all three go on the back side of the wheel plate. The video also showed the solution to the puzzle of the hand brake lever and rubber cover positioning while inserting the shims. The reason why the hand brake lever was not engaging the brake shoe was because another video had indicated placing 2 of the shims on the front side of the plate and 2 on the back. This does not allow the lever to engage the shoe. Learned in other discussions that the rear cylinders are to be greased such that they float in the slots. The Japanese had interesting designs but as we know they borrow many of them.
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Re: wheel cylinder fitment

Post by Solex68 »

Cahhh68 wrote: Sat Mar 26, 2022 10:43 am Having watched a very helpful video,
It it possible to add the link to the video?
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Cahhh68
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Re: rear brake springs

Post by Cahhh68 »

Here is the video link in which I learned proper shim placement on wheel cylinders and process of getting all the parts back together in proper order which I think may be the only order they will go in, including the hand brake lever and the rubber.
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Re: rear brake springs

Post by Solex68 »

Thanks Cahhh68 !
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