March 2010

A PRESERVATION TIP
By Jim Elliott
There is a drain hole at the bottom of each end of the rear ‟48-‟49 Cadillac bumper where an upright brace is welded on the
inside of the bumper (by the large cheek of the upright under the tail light). The hole, the size of your finger, is not round but
rather of an odd shape as it is formed by the brace welded to the bottom of the bumper. It is apparently to drain out the water
that will collect inside of the mounting brace that is welded to the back of the bumper at that point. If you lay on the ground
and look under the rear bumper you will see what I am talking about.
Well, when I took off my rear bumper for plating I noticed that a large nut was wedged in one of the holes. When I tried to pop
it out with a screwdriver it would not budge. When I tried a long drift punch and a hammer I got a large amount of small rocks
and sand. Both sides were plugged up. I had to put the bumper in my sand blaster to really clean the area up for plating and
got enough sand and rocks to fill two coke cans. My suggestion is that when you wash your car you should give these two
holes a very generous spray of high pressure water. Incidentally, I have wondered why the „49s I have seen in junk yards have
rusted out rear bumpers; now I know.
1949 SERIES 62 4-DOOR SEDAN BELONGING TO JOHN WASHBURN OF ELIZABETH, COLORADO
DID YOU KNOW THAT…..
By Jay Friedman
…your „49‟s rear axle housing has a built-in air vent in the case? I certainly didn‟t.
Some background: When I bought my 6107 25 years ago the differential pinion seal was leaking. The mechanic who replaced
it looked everywhere on the axle housing and could not find a vent to the atmosphere. In addition to the motor, he said these
were necessary on all housings that contained a rotating mechanism in gear oil, including the rear end and transmission, to
prevent oil pressure building up which can cause leaks and the oil to foam (which reduces its ability to lubricate). To rectify
this he drilled and threaded a hole above the right-side spring and screwed in a small venting valve he took from a junked car.
I had no further problems in this area until recently, when my rear axle housing started leaking gear oil on the right side at the
junction of the axle housing and the passenger‟s side brake backing plate. (There‟s a special channel at that point to direct
away from the brake shoes any gear oil leaking past the axle seal.) It was a small leak, but it became very annoying to see it
whenever I climbed under the rear of car for any reason. I replaced the axle seal, and even installed a spare axle shaft on the
assumption that might help, but the leak persisted.
Thinking the leak might be due to a crack or flaw in the axle housing, I bought a used one from ‟49er Joe Cutler and started the
formidable task of removing and replacing it. However, while cleaning up my new purchase I noticed a slit-like hole on the
upper right of the back of the round part of the housing, which is the long-lost air vent. (See arrow in photo on next page.)