Packard Forum Index » Pre-War (1899-1942)

no question - I agree with JW that the guy is a "genius".

No question, the article was great, and I agree also with JW's comments that we would have liked even more detail and info.

To be "picky", I would note I am unclear, however, how he got the idea that Packard rod bearings had "bronze" in them. Yes, the original "insert" type rod bearings introduced for 1935 production had a "BRONZE" color. They were a joint effort by Federal Mogul (which is where Packard got em) and were a "sintered COPPER lead" not bronze). I dont know enough about metalurgy to suggest well a "BRONZE" insert will behave on a "hardened" Packard crank-pin compared to copper.

There was some fooling around with a "cad.silver" bearing surface ( a set was found once in a Packard I helped pull apart;) probably the result of a field overhaul during or after World War II. At some point in time, Federal Mogul was selling to Packard the "cad silver" insert, as a substitute for copper, which was a "vital defense metal".

I dont know enough about metalurgy to suggest well a "BRONZE" insert will behave on a "hardened" Packard crank-pin compared to copper.

I think you want to go back and read that section again. The final friction surface of the insert was tin, not bronze. Bronze was used as the matrix to support the tin.

Quote:

PFHartmann doesn't know enough about anything. You must have been bored to come back here Petey!

Of course Owen is correct - most, if not all con. rod "inserts" are multi-layer, with the actual bearing surface that "rides" on the crank-pin being a very thin often PLATED layer of soft metal for "embedability" reasons.

Owen - be assured I read that fellow's article with a great deal of admiration and enthusiasm. And I read it CAREFULLY.

Again, the Federal Mogul "inserts" that were introduced for 1935 WERE NOT BRONZE. The guy was just plain wrong not only about WHEN they were introduced, but WHAT they were made of. Also, if my "hunch" is correct, he also mis-diagnosed a partial bearing failure of an insert that he showed in a photo. Looked to me like typical acid-etching failure, typical of the low grade motor oils (compared to todays) that werent changed often enough.

What concerns me about bronze is that it is considerably "harder" than the relatively soft "copper lead" concept that Federam Mogul finally decided on, and that is still the "gold standard" for extreme service use today!

I get a little nervous when, no matter how well meaning, guys try to "out-guess" or "out-do" the professional engineers. Maybe it dosnt matter that the material under that thin plated layer of soft metal is much MUCH HARDER than the copper Federal Mogul decided on. I just dont know.

I am just glad to see a guy in the restoration business who cares enough to try and come up with an answer to an otherwise difficult problem to solve ( i.e. no rod bearings for "big" / Senior Packards .

SIDE NOTE TO TURBO:
How about helping us guys out with technical info. that benefits fellow Packard owners, and stow the hostility.

How about you blow it out your arse Petey???

Just ran across this after looking at our site's tracking info.

Ya'll have Dale's permission, at least, to use the articles - but it would be important to get permission from Cars and Parts for any reprinting. I loaded them on our website for informational use.

As for this Pete guy... dunno what to say about him. Seems he's gotten quite the negative press on the forums. All I know is that the engines my father have redone run absolutely marvellously. Dave Kane drove the '34 Dietrich we restored in the early 90's on the 2006? (I think) Pebble Beach tour for 1,700 miles with no problems. If we're guilty of anything it's that we make them better than they were when new - no reason not to!

Regardless, if people have further questions unanswered in the articles, feel free to e-mail Dale at dale@daleadamsenterprises.com. I'll see if he can answer them for you. My mother and I are trying to talk him into writing more articles.

Theoretically, the hardness of the bearing material should not matter in a properly designed motor. Rolls-Royce used a very soft babbitt with high longevity. It was softer than plastic. Packard bearing technology followed the research published by Wright and Taylor in 1925 by which bearing characteristics technology became fully developed. Not all manufacturers followed this technology - most notably Lycoming - and suffered from poor connecting rod bearing life. The Packard V-12 was not designed following Wright and Taylor and thus had more rod bearing problems than Packard eights.

To determine which bearing method works best requires a teardown. Even on these motors with new parts the results may be pretty surprising. I did some repair work on a V-12 and found the condition of the inserts downright shocking. I attribute this problem to infrequent oil changes and lousy filtration.

The principal advantage of the insert bearing is superior heat transfer and cooling especially at high RPMs. This is achieved via the pre-loaded nature of the bearing insert.