Drums won't fit back on ....

[Hey78isgreat]

HELP! My husband changed the right rear wheel cylinders on his 280Z. While he was doing it, he replaced the brake shoes. Now he can't seem to get the drum back on the back wheels. He didn't keep the old shoes but said they looked identical to the new ones - that the new ones just looked "new" and "slightly thicker". He said the drums had never been removed and were kind of tight coming off.

Does anyone know what could be the problem? Is there a "trick" to putting the drums back on????

[Arne]

If he hasn't backed off the adjustment after installing new shoes, the drum won't fit. He should back the adjusters all the way, fit the drum on and then adjust the rear brakes. Might need to back off the parking brake adjustment as well.

[Chino 240Z]

The adjuster wheel is the small wheel often called the "star-wheel" located at the bottem center between the 2 shoes. It will automatically screw out and expand the brakeshoes as they wear so the shoes stay close to the drums. When you replace with new shoes they will have thicker brakelining compared to the old worn shoes. Therefore you will need to turn the star wheel in the opposite direction to colaps the shoes together so the drum will fit back on.

You may need to gently hold down the small lever away from the adjuster wheel so it will turn. It will be easier to close the adjuster-wheel if it was out while the shoes are off, but can easily be done with your fingers and a screw-driver after installed too. Once the new shoes are adjusted together inward and the drum fits back on, you will want to adjust or turn the star-wheel back out so that the drum slightly touches or drags a tiny bit on the shoes when you turn the it. You can hear the shoes touching as you spin the drum and that should be good to go.

Sometimes even if the starwheel is adjusted all the way closed, you will have a tough time getting the drum over the fresh or new shoes, and that is when you push the shoes a little back and forth to get them centered and aligned so that the drum slides over the new shoes. Couple curse words always come about this time too.

These rear drum type brakes will adjust automatically out to the drum when you apply the brake in reverse. The reverse action pushing on the shoes will cause the lever to actuate and turn the starwheel a tiny bit to push the shoes outward keeping them close to the drum.

Hope this make a little sense?

Let me know if it doesn't work, I can swing by afte work and give ya a hand. I work in Colton and pass by Ontario on my way home to Chino.

Cheers,

Craig

[Fun_in_my_z]

I had the same problem. I ajusted them back in as far as they would go and the drums still would not fit. I got the drums turned and they fit as good as new.

[Arne]

These rear drum type brakes will adjust automatically out to the drum when you apply the brake in reverse. The reverse action pushing on the shoes will cause the lever to actuate and turn the starwheel a tiny bit to push the shoes outward keeping them close to the drum.

That may be true for the later Z's, but definitely not for the early 240Zs. For the '70 and '71 240Z, here is the direct quote from the FSM:

"When the hand brake is operated, the wheel cylinder lever turns the adjust wheel, and thus, clearance between the brake shoe and the brake drum is adjusted automatically."

In fact, in my experience the cars that adjust by braking in reverse are few, especially these days. Mostly big old American iron. Most imports that had self-adjusting drum brakes require regular use of the parking brake to keep the rear brakes adjusted. I suspect the later Zs use this design also.

[sblake01]

That's how they adjust on my 78 280Z as well as on my 79 810. By pulling up the emergency brake. But you have to get the drums on first. When replacing the shoes, I always back off the adjustment before I put the new shoes on. The drum will slide on easily then I tighten the adjustment with the star wheel until I have just a slight contact between the shoes and drums. Put it all back together, wheels back on, hit the pedal a couple of times, and adjust it the rest of the way by holding the release button on the emergency brake lever in and pulling the lever up three or four times. Done. And Bill, unless your drums were in really bad shape, they should have gone on. I've never had that problem. And by the way, Hey78isgreat, welcome! What part of Ontario do you live in? My brother lives there and I'm just a few miles away.

[mdbrandy]

And Bill, unless your drums were in really bad shape, they should have gone on. I've never had that problem.

I agree, however, one thing that I've found is that there is always a "ring" of corrosion around the outer edge of the interior of the drum where the shoes don't contact. That corrosion can actually be fairly thick, and I've had it make life really annoying. Turning fixes that, of course, but sometimes a good wire brushing just around that edge will knock it down.

Just a thought .

Mark

[Chino 240Z]

I'm sorry I agree with the hand brake too, I'm doing more brake jobs on domestic vehicles and keep forgetting about hand brake use is what adjusts out the shoes on a Z. Besides my Z (track use only) doesn't have a hand brake so I forgot. It's junk removed on track cars, it's a weight thing and if the hand brake is used you could do more harm warping a drum or rotor applying a hand brake while hot off the track. So in our case we bleed, clean and adjust by hand after every event. So I forgot about the hand brake on the Z, I do recall expanding them 15 years ago on my stock 72. My bad.

[Arne]

I figured you didn't have a hand brake on your car, Craig. I certainly wouldn't have one on a track car either.

[Hey78isgreat]

Hey Everyone -

Just wanted to say "THANKS" for the tips and advice - the Brake problem has now been solved - backing off the adjustment and then putting the drum on worked. My husband thanks you too!

: )