Packard Forum Index » V-8 (1955-56)

From the 1959 date on the SSB, are we to assume the forged crankshaft was only available after that date and never installed in production?

I've always been told a forging die and the resulting crankshaft is more expensive than a casting. Seems odd S-P would pay for a forging die for the few crankshaft sales likely after 1959. This at the same time they still have complete long-block engines for sale for $225. One would think it would have been less expensive just to send anyone a complete engine, rather than engineer and produce a forged crankshaft.

FWIW, I've never pulled down an engine which had a forged crank in it and have only ever seen four or five of them. A friend in NJ just had the good fortune to find one inside the engine he is building up with performance parts, so best possible start. Proves a few are still out there.

As to the differences between 320" and 352"/374" cranks; they're not what one might expect. The dimensions of the counterweights appear and measure identical.

The 320", with lighter pistons, has two balancing holes drilled in the front and rear counterweights. The outer edge of the counterweights are as-cast, not lathe-trimmed

The 352'/374", with heavier pistons has three holes in the front and rear counterweights. The outer edge of the counterweights are lathe trimmed.

This seems counterintuitive, as heavier pistons should require heavier counterweights to offset them.

I'm going to ask my balancing expert to explain WTFIGO.

jack vines

Since the 352/374 crank is lathe trimmed then maybe try a trial fit of 374 piston and rod to the 320 crank (that is not lathe trimmed) to see if there is piston/counterweight interference.

quote:
" Seems odd S-P would pay for a forging die for the few crankshaft sales likely after 1959. This at the same time they still have complete long-block engines for sale for $225. "

How late were left over engines used for Marine or other applications??? Maybe marine or some industrial use applications of the engines were breaking cranks or experiencing other premature problems while in service (sustained high RPM or other severe service application) , thus a new long block even if for free would have been a poor solutuion to those wanting an engine to live rather than have to replace one on short intervals.

Maybe the NEW left over long blocks sold in large quantities had cranks replaced with forged cranks before installation.

Any number of possibilities outside of passenger car applications.

As for the balancing issue:

Use 2wo pieces of angle iron or similar item to resemble verticle 'knife edges'. One piece of angle iron on a table to the left, another piece of angel iron on a differnt table to the rite. Space tables apart from each other not quite distance of the crank length.
Place crank on knife edges, rear main on one knife edge, front main on other knife edge. ROTATE (roll) crank along knife edges backwards and forwards. Crank should NOT ROLL OF IT"S OWN WEIGHT regardles of where the counterweights are positioned, up,down, to the left or rite or at ANY position.

Maybe just "urban legend", but I've heard more than once that the forged cranks are found more often in the Hash engines. I'll soon be opening up a 1955 marine conversion engine and it will be interesting to see which oil pump and crank is inside.

Quote:That's a big maybe without any documentation whatsoever. There were no Packard V8 engines built by S-P specially for marine use. All those sold to marine conversion shops were left-over passenger car engines sold as surplus and without any S-P warranty.

There were no more engines built after car production ceased. No need of it, as there were still several hundred complete engines and service long/short blocks left over. There's also no evidence S-P ever tore into any completed engine, long block or short block to install a forged crankshaft.

Note in the 1959 SSB, they were still selling '55 production long blocks with the weaker main caps and valve retainers.

SASCO still had complete '56 Golden Hawk engines for $395 as late as 1964.

Bottom line - is there any documentation of a production installation of the forged crankshaft or any mention at all prior to the 1959 SSB?

Quote: News to me with regard to automotive engines. I've seen motorcycle and small engine shops do that, but in fifty years, I've never seen anyone statically balance an automotive crankshaft. The shops I work with balance dynamically; the crankshaft is spun on a machine, with bob weights representing a calculated portion of the weight of the piston, pin, rings, locks, rods and bearings, attached to the rod journals. Counterweights are drilled, or heavy metal welded as required.

A FWIW, but Packard was the only manufacturer I know of to do the final balance of an assembled engine. They spun up the assembled engine with a 50hp motor and did a final tweek, drilling the crankshaft damper or welding weights on the torque converter.

jack vines

I don't understand all the wild/unsubstantiated supposition concerning forged replacement crankshafts. They were probably produced by Studebaker's supplier. Packard was going out of business. Studebaker never went to cast cranks, so it seems logical that replacement cranks would be ordered thru Studebaker. They went to the company who supplied their cranks, and thus it was a given that the cranks were forged.
No big mystery - and no wild suppositions needed. A simple business decision.

Quote:Yes, could have happened that way.

On the other hand, I was in the foundry business in another life. It is always much less expensive to continue having the cranks cast by the original Packard supplier.

One possibility is by 1959, when they decided they needed more service crankshafts, the original cast patterns had been destroyed. Maybe then, they gave the work to the forging shop which produced Studebaker cranks.

Still would like to know if there's any documentation of the forged cranks prior to that 1959 SSB.

jack vines

ok. So Studebaker used only (or a large number of) forged cranks in production Studebaker engines????? If answer is yes then most likely that is new news to alot of us.

As for the knife edge balance routine i mentioned above i was in no way recommending nor not recommending to use that method to make ANY balance changes. I only indicated the knife edge method as a cursory CHECK of the balance and expected results.

To me, the 1959 date of that bulletin merely tells us when supplies of the original crankshafts, as originally installed by the Utica plant for 55-56 Packard V8s and supplied for service, were running out and that the other P/Ns were to "now" be substituted.

One should not assume that the replacing parts or numbers were newly issued at that time.

Let's consider the replacing part numbers. Generally, part numbers are simply issued in sequence. Also, Packard began prefixing their P/Ns with a "6" at some point in 1955-56, to avoid conflict with Studebakers own P/N sequence as pats warehousing and distribution operations were merged.

Notice, if only by virtue of their sequence, that P/N 440989 precedes the OE 476009 for 5560-80 and 56th; similarly, P/N 440912 precedes the OE 440954 for 5522-42-47. None of these four P/Ns are 7-digit P/N that used the "6" prefix.

This suggests to me that the forged cranks were already in production, and concurrently with the OE cast type, but for some application other than Packard vehicles.

I don't have any Nash/Hudson/AM parts books, but wonder what they show for P/Ns. I also wonder if Packard sold - if only as a middleman - forged cranks for marine conversions?

As for the continuity of parts production after 1956, I have to wonder how many of Packard's suppliers were shuttered - caught in the undertow of the S-P "rescue", like so many contract suppliers in the wake of the automaker bailouts of more recent years.