March brake thought for the month. Hardware

[brian]

The proper hardware for a drum brake system is critical. So is the quality. I have found some of the offshore stuff less than desirable and use Bendix US made kits. Part numbers H7162 and H 7179 is what I use. I do not have to double up the return springs with good quality kits either.

Using the proper hold down springs is critical. If the pin is too short, the shoe will not be free enough to move and float to match the drum, a pin too long won't hold the retaining clip and could cause real problems. The hold down spring should be tight enough to stabilize the shoe and still allow it to move fore and aft. I always bump the shoe back and forth with my palm to make sure they're free. A sticking shoe is a major reason for rubbing shoes while adjusting.

The shoe tends to move towards the adjusters when the wheel cylinder expands. If you have the improved, later model angled adjusters, this movement will tend to move the shoe outwards towards the drum and maximize the contact area. If the hold down spring is too tight or if the contact points on the backing plate are grooved from wear, this sliding action is impaired.

If you are finding bent pins on the hold down assembly, chances are they are too short and binding the shoe.

Next month's subject will be drums. Be safe out there.

[tiagosantos]

discbrakesdiscbrakesdiscbrakes!

Just kidding.. Thanks for posting this stuff Brian, it's really helpful!

[BLS]

If the pin is too short, the shoe will not be free enough to move and float to match the drum

To Brian's point, I have new front and rear spring kits that say they are US made (not bendix). Both the front and rear hold down pins and springs are the same length. Correct for the rear shoes which are narrower, but completely wrong for the front shoes. The picture shows the difference. The older long pin and short spring (left side in picture) is the correct one for the front. The short pin is correct for the rear but I'm not sure about the longer spring. I haven't gotten to the rear just yet.

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[brian]

Generally, the spring and pin are paired together. It's likely the long spring on the short pin will be too tight. After installing the tie down assembly, make sure the show will slide back and forth.

[BLS]

Brian, the long spring and short pin are the same in both kits, front and rear, obviously wrong. It would not work at all on the front and maybe will work on the rear, haven't gotten there yet. The long spring will work with the long pin on the front, but since the short spring on the long pin seems to yield plenty of hold down force and the shoes will slide easily, I went with that combination. The difference in the long and short pin is about right given the brake shoe width difference front to rear. I think the short pin will be fine on the rear but I have doubts about the long spring. I may use some short springs for the rear as well.

Your tips are appreciated I had it on my mind as I worked on the front brake system...

Picture of left front with NOS hand arched Ferrodo brake lining

Regards,
Barry

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[brian]

Yes, BLS that sounds like a plan. Sometimes it's easier for vendors to cover several models and years with their kits rather than separate kits so the spring assortment doesn't surprise me.

[FV80]

Barry,
Where did you get the Ferrodo shoes ?? Do you have any experience with them? Do they work for our cars ? Cost ?
Steve, FV80

[BLS]

Steve,

They are linings I had stored away thus the "NOS" designation. It stands for new, old stock. In this case it means I had them stored away for the last 30+ years. Ferrodo does not list any VW shoes/linings anymore so apparently they do not make them anymore. Compared to standard shoes they were quite good, compared to carbo's or other available shoes I don't know of course. The ferrodo's were alway sold as linings which you then had to rivet to your own shoes. I only have the one set and after arching them to fit my turned drums they're probably not going to last very long.

Sorry if it looked like there was new source...

Regards,
Barry