1979 Block Casting Date Code on 14016379 blocks

[Tom R.]

in 1979, a one-year only block was introduced in Corvettes with a casting number of 14016379 beginning with VIN sequence 39,000. Apparently, with 53,000 Corvette units to be built, plants were scrambling for more blocks.

It seems the block cast date code used a format not consistent with that used on the 3970010 blocks...but in the same location. The image below shows a casting date code of 71. My guess is given a one-year only block, the alpha code and year code were dropped and what we have is a modified Julian code of 71. Given that assumption...79s built with the 1401 block began in June 1979. The 71 code suggests a March 12th 1979 production code.

What am I missing here? This block is installed in a 78 Pace Car...my guess...replaced under warranty a year later.

[Joe L.]

Re: 1979 Block Casting Date Code on 14016379 blocks

Tom------


I don't know what that date coding denotes. However, I strongly suspect that this block was cast somewhere other than Saginaw. I would suspect St. Catherines, Canada or Defiance, OH. I just cannot see either Saginaw or Tonawanda using a date coding system like that.

Is there a "K" cast anywhere on the block?

[Tom R.]

Re: 1979 Block Casting Date Code on 14016379 blocks

What would the K represent...month? It could be in a separate stencil...like the tire TIN codes evolved to become.

[Joe L.]

Re: 1979 Block Casting Date Code on 14016379 blocks

What would the K represent...month? It could be in a separate stencil...like the tire TIN codes evolved to become.

Tom------


"K" is a foundry identification mark used by the St. Catherines, ONT foundry.

[Terry M.]

Re: 1979 Block Casting Date Code on 14016379 blocks

in 1979, a one-year only block was introduced in Corvettes with a casting number of 14016379 beginning with VIN sequence 39,000. Apparently, with 53,000 Corvette units to be built, plants were scrambling for more blocks.

It seems the block cast date code used a format not consistent with that used on the 3970010 blocks...but in the same location. The image below shows a casting date code of 71. My guess is given a one-year only block, the alpha code and year code were dropped and what we have is a modified Julian code of 71. Given that assumption...79s built with the 1401 block began in June 1979. The 71 code suggests a March 12th 1979 production code.

What am I missing here? This block is installed in a 78 Pace Car...my guess...replaced under warranty a year later.

Tom
In the 1968-72 area we sometimes see engine blocks with a MXX in the date code area. When we questioned folks who worked at Saginaw it turns out these were "test" castings using some non-standard feature (a slightly different alloy or slight casting configuration differences). If that feature didn't interfere with normal engine assembly operations (and it usually didn't) some of these found their way into production vehicles. In these cases we have no discernible cylinder case casting date.

Could this be another means of identifying "test" castings? Sadly my contacts at Saginaw have either retired or passed away, so I can no longer help you there.

In this case, what does the pad assembly code reveal?

[Tom R.]

Re: 1979 Block Casting Date Code on 14016379 blocks

Not much! It is blank. This motor is in a 15k Pace Car. My speculation...block replaced under warranty one-year after production with a then 79 motor.

[Terry M.]

Re: 1979 Block Casting Date Code on 14016379 blocks

Not much! It is blank. This motor is in a 15k Pace Car. My speculation...block replaced under warranty one-year after production with a then 79 motor.

If replaced under warrantee I would expect at least an assembly date code -- but by the late 1970s practices may have changed. It is also possible they replaced only the cylinder case or used a fitted case and I doubt either of those would have an assembly date stamped on the pad.
Interesting situation. It sounds like tracking down previous owners is the only solution. Then hope they are candid and honest.

[Tom R.]

Re: 1979 Block Casting Date Code on 14016379 blocks

Tom------


I don't know what that date coding denotes. However, I strongly suspect that this block was cast somewhere other than Saginaw. I would suspect St. Catherines, Canada or Defiance, OH. I just cannot see either Saginaw or Tonawanda using a date coding system like that.

Is there a "K" cast anywhere on the block?

Could not find a "K" but on driver's side, found "CFO." Also note the distributor date code A10

[Joe L.]

Re: 1979 Block Casting Date Code on 14016379 blocks

Could not find a "K" but on driver's side, found "CFO." Also note the distributor date code A10

Tom------


It's actually "CFD" plus the "wagon wheel". The was the foundry mark for "Central Casting Division". It actually applied to all GM foundries and does not identify a particular one. However, I've rarely seen Saginaw Gray Iron ever use it. Tonawanda used it but not very often on blocks or heads. So, in this case, I'd say we're back to St. Catherines, ONT or Defiance, OH. The foundry that used to almost always included the "CFD" was Danville, IL. However, that was a malleable iron foundry and, as far as I know, did not cast engine blocks.