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I just completed the teardown, cleaning, and honing of the brake master cylinder on our '48 Deluxe 8 sedan. It cleaned up beautifully with very minor honing. The large port where fluid enters the piston area is nice and clear, but the smaller compensating port, the one through which the fluid returns to the reservoir, appears to be completely blocked. I've tried to push a small diameter stiff wire through it, to no avail. I'm wondering if I can drill it clear, but don't know what the diameter is supposed to be.Is the diameter even critical? I've looked at the illustrations in the service manual (figure 5, on page 4 of the brake section in my manual)and it looks like maybe 1/16", but I'm not sure. Can anybody help me out here?
Thanks, Kelly

2106 & 2206 master has what appears to be around an .025 opening. It does appear large in this photo but after trying a number 60 (.040) drill and then .030 wire without success, .022 wire passes easily yet .030 will not. Unknown if that part is the same since the 22nd deluxe and custom do use different cylinders. As comparison, the large hole on this one is slightly larger than a #3 drill or around .213.

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Dear Kelly:

To be sure the diameter is no longer what it used to be due to rust but it was a calibrated orifice

I would try heating the hole with a propane torch, then take it to a local place and blow compressed air through it.

Also, wash the thing out with detergent and water, rinse with alcohol, dry with a cloth, then immediately rinse with brake fluid. This will remove gritty abrasives that will damage seals.

thanks fellas. Going back for another look.

Drilled the compensating port at .030. The brakes work just fine, so I guess that was an okay thing to do.
Got it going and got it stopping. Now, if I can just get the bottom section of radiator hose to stop leaking coolant. Wow that thing is a bear to get at!
Thanks for your help fellas. It is much appreciated!
Kelly

An old mechanic's trick was to paint the inside of the hose with shellac before installing it. I have used the non-hardening Permatex with good luck on my 51. Couldn't get the durn thing to stop slowly dripping prior to that.

I hate having the radiator hoses stick when I am trying to remove them, so I never use anything like shellac. Instead I use white brake lubricant. This eases the installation and removal. The grease seals little pinhole gaps between the hose barb and the hose. Water does not mix with grease so this method works well on old parts with a rough surface.

I've always used 3M weatherstrip adhesive (yellow). I learned this from a master mechanic when I was in Art School in Memphis in the early seventies, working part time as a mechanic. It helps the hose slide on, and gives a very good seal. I wouldn't worry too much about removal- unless you're twenty years old and plan to drive it every day!

Always wondered when the modern, superior worm-style hose clamps first appeared. An auld auto/aircraft/machinist friend who was around then says during WWII. Anyone know for sure, first application(s)? The CCCA still deducts points if you use anything but the original Mickey Mouse wire clamps on '30s cars, and i believe 1940, maybe '41.

If your '48 327/radiator proximity is cramped as a '42-'47 356 Clipper, i feel your pain. Though mine wasn't seeping, as part of maintenance neurosis i decided to check that lower hose clamp for snugness. Had to find a stubbie screwdriver that still had just enough length to get leverage. Fun.

Been on vacation for a couple of weeks, so haven't had to deal with the leaky hose. Tomorrow, a checkup with the cardiologist to make sure my replaced aortic valve is still doing okay (wish me luck), then back home to New Mexico and the leaky hose. It's an annoying problem, but at the end of the day, no big deal!
Thanks for the input. Lots of good solution to ponder.
Kelly