28Q29U Plymouth Forum

General Category => General Discussion => Topic started by: ski on August 30, 2008, 08:48:19 PM

Title: Brake drums
Post by: ski on August 30, 2008, 08:48:19 PM
I've got my master cylinder and front slave cylinders sorted out thanks to the tips I've got from Chet and the rest of you guys.  I ordered new brake lines the other day.  After trying to remove the rears and reading old posts here I am going to try to get a puller together after the long weekend.  When I removed the driver's side drum I noticed it was pretty grooved and worn.  Does anyone have specs on diamater and max. turning.  Are there replacements available?  I know an old school brake rebuilder that I'd bet can resurface them but I won't make it over there until Mon.  Anyone have any experience in this department? 

ski
Title: Re: Brake drums
Post by: chetbrz on September 02, 2008, 09:06:01 AM
Ski,

The following is just my opinion and I don't know how valid it is. 

Remember just my opinion;

Judging by the thickness of the brake drums on the 28 & 29 Plymouth I am assuming that they weren't designed to be resurfaced like modern drums.   I am sure that any mechanic, shade tree or otherwise would clean up a drum in reasonably good shape with emery cloth or quite possibly mount the drums on a motorized device and sand and polish the inner drum surface.

I checked my 1924 Chilton Automobile Directory of Replacement Parts Buyers and found nothing on Drum resurfacing equipment.  I found plenty of machines for other purposes like Brake Band Riveting but none for drum resurfacing.  My guess is that drums of the time were throwaway and replace. 

Keep in mind that these vehicles are low speed so I wouldn't get totally hung up on creating a perfectly pristine drum surfaces.  If you can great, but in reality these cars will rarely surpass speeds of 50 mph and most of your driving is in the 25 to 45 mph area.  Some groves in the drum surface may create an annoying squeak but with the amount of miles these cars are driven it could take years to develop.

If you do mount these drums on a resurface machine I would take off 0.020 +- 0.010 of an inch and call it quits.  What is left should work for a good long time so you can still use the car while you search for replacement drums.

Just my two & one half cents,   

Good Luck,  Chet...
Title: Re: Brake drums
Post by: ski on September 02, 2008, 11:38:59 AM
Thanks Chet, I was thinking along the same lines.  I doubt I'll ever get above 35 MPH at least for a while since tires etc are kind of marginal.  So far only the one looks "bad".  I would like to get another better drum at some point so I can make a brake adjusting drum out of the ate up one.

ski
Title: Re: Brake drums
Post by: 29UJohn on November 03, 2008, 10:56:16 PM
I agree.

I had my brake drums turned - and did not have to remove the drums from the wood spoke wheels.  The brake shop enjoyed doing the work - they do not see many of those!  They also relined all the shoes and ground them to fit the drums.  Probably more than I needed to do, but I drive my car a lot.  The brakes work great.
Title: Re: Brake drums
Post by: Satillite70 on November 11, 2008, 07:28:30 PM

    I was thinking about this also, when I drive my 28 Q the break pedal pulsates slightly under breaking.  You can feel the car doing the same.  The drums are grooved and must be slightly out of round as well.  I would suggest that maybe the wear was caused by mud, the old roads were mostly muck and I'm sure that mine at least held a lot of dirt and debris.

  They do stop the car though, so it hasn't been a big issue to me.  I will look at turning when relining is required.

Chris