I was adjusting the brakes on my '26 roadster and noticed the rivets were loose on the driving plate. I could see the movement when I put the brakes on. Should I stop driving now or can this slide till winter? How common is this and what's the best fix? Thanks, PK.
If they aren't that bad wait until winter. I wouldn't even mess with them. Driving plates are common, just make sure you get the improved style.
Depends how loose they are I guess. With those rivets loose, the output shaft can wobble around some and give little or no support to the rear end of the transmission. This puts a strain on your crankshaft flange and could lead to a broken crank. One of our local chapter members, who had a broken crank, also had this problem. We pretty much determined the loose output shaft was the cause.
If you can just see slight shifting, maybe it's o.k. for a while but I wouldn't allow much.
What does the improved style look like? A friend has about a dozen of them in a box. PK
Pat, try different driven plates in your drum until you find one that fits. The earlier plate won't go in your drum. It will probably be ok until winter, if there is only a very small amount of play but, if it were my car I would stop driving it. The rivets are already loose and the more you drive the car the worse it's going to get. The brake drum stops the car through those rivets and if they shear the transmission brake won't work anymore.
Be sure to check the replacement one for cracks. I am finding lots of cracked ones. Dan
Is your handbrake in good working order? You will need to grab it quickly when the rivets let go In a panic stop!
Loose drive plate rivets can be the result of a misaligned fourth main.
By the way - that was my drive plate above. It's in Canada now...
The 26-7 plate fits inside the wide drum, so it is smaller in diameter than the early ones. On the early ones, the outside edge of the plate forms part of the brake drum surface. Consequently, it is often polished and worn unevenly. This may help you to pick out the correct one from your friend's stash. When it comes time to fit it you will know if you picked the right one.
Hope this helps.
Allan from down under.
Looks like the motor is coming out. I have a tour coming up in six weeks. All our driving is in the mountains so hills are the rule. I can see how this deal could ruin your day. The picture and explanation was a big help. I'll be able to snag the right one. Can the rivets be replaced or tightened to save all that material? PK
Simple. Replace the old rivets, as they wear out over time. They are probably as old as the car. Go figure.
Got it partly disassembled? If so, then disassemble the entire mechanism and fix the problem.
You'll be glad you did, as you will probably find other hidden problems when you do so.
If you tighten the old rivets they will not fill the hole and you will soon be back in the same predicament. Get new rivets and set them securely. You will need to squeeze them so that they fill the hole completely.
Get you handbrake in good working order before you head out on tour.
Oversize as well as standard rivets are available. If you have loose rivets, my guess is you will need the oversize. http://www.snydersantiqueauto.com/oversize-driven-plate-rivet
Be prepared to be finding another plate even if you get over sized rivets. I have two on my shelf that even the over sized were too small. Not only that, the holes were oblong. Because of the shape of the rivet head you can't just run down to you rivet store and buy ones that fit.
Forgot to mention. Driven plates are prone to cracks. So carefully inspect the plate when you get it out.
If you replace the plate, be sure the replacement has the plug in the shaft. I have to drain oil from my Ruckstell after every tour.
What diameter should I read where the fourth main rides? Thanks for the heads up on the plug. I'm learning lots about a part I never knew existed. PK