6.2/6.5 Cylinder Block Date Code
http://www.thedieselpageforums.com/p...ckdatecode.jpg
What month, day and year was this 6.5L block cast? :)
To answer the question... All of the 6.2L/6.5L cylinder block casting dates up through November 2001 used 4 digits. The reality is though, that GM stopped casting these cylinder blocks well before the November 2001 hand-off to AM General.
The beginning letter (A, B, C, etc) indicates the month; A=January, B=February, etc.; the "C" in this case tells us it was March. GM didn't use some of the letters of the alphabet in any casting codes because of a possible confusion with a number, such as the letter I or O. The next two digits in the above block code shown indicate the day of the month that this block was cast; in this case the "06" indicates the 6th day of the month. The fourth digit indicates the year in which the casting was made; in this case 199"6", because we know it's a pre-oil spray 6.5L block. So this 6.5L block was cast on March 6, 1996.
With just one digit indicating casting date year, you have put the block into context with what we know the 6.2L/6.5L production to get the right year.
Jim
Late 6.5 Date codes and other block info
Any replies to this post can be made on the 6.5 forum, lets keep this thread short and clean (MISSY) :)
Here is the real deal on the late 6.5 Block date codes
POST 2000
Starting in the 2001 year, GEP/AMG had taken over production of the 6.5 from GM
The date codes are a tad bit different 00 00 * letter code
The new codes start with H which is 2001 and the I is skipped due to its easy of confusion with the number 1
H=2001
J=2002
K=2003
L=2004 and on in the series
The first two digits are month
The second digits are the day
The last digit is the year
06 10 J would be June 10 2002
The late blocks also have the <> diamond in the valley towards the front
There is also a flat pad (drilled or not) for the rear turbo mount if used.
The LH side of the block has a slightly different machined pad configuration around the motor mount area.
All the bolt holes are metric as in the last few years of GM engines.
The casting numbers end with 506
The oil cooler ports are 5/8 pipe thread
The oil squirters and such are the same as the late GM blocks.
Also of interest
I scrounged up one of the 2002 GEP Blocks recently, this block is the same casting that is used in the Optimizer 6500
These blocks I am told by GEP folks were not supposed to be sold, but that some got loose from Navistar in 2002 and wound up in the general publics grasp :)
There is a very limited number of these blocks out there and the current attitude of GEP is that only complete long engines will be sold.
************************************************** *****
The other stories about the CAST IN CANADA blocks and such are all just BS according to the GEP rep.
These aftermarket blocks are all "CHINESE", cast and machined.
The testing that was done I am told on these blocks revealed that some of them have "CORE SHIFT" and some cylinders may be 3/8 thick on one side and 1/8th thick elsewhere.
Some seem fine they said, and others are just scrap iron.
If a chinese block can be ultrasound tested and if it has no appreciable core shift, they may well be fine, but without knowing this info, they could be a BOMB too :eek:
I also learned that GEP has in its hands a Direct injected 6.5 engine.
This was done using a standadyne pump and pencil injectors.
There were at one time (2) TWO OF THESE, one has since met its demise and the one test engine left is at the GEP plant being used as a test bed.
There is I am told an ongoing project to refit the P400 with a common rail direct inject head using piezo injectors.
How and when this will come to fruition, I do not know.
I was told that with the P400's strength that the direct inject setup will show some serious power increases.
The information I got, was that a optimizer 6500 can handle 225 HP easily.
With what More power accomplished with the "Power Project" its my feeling that the Navistar block equiped with a good crank (Scat or a forged one) could easily handle far more than 225 HP and live well.
Sooooo, if you stumble onto a Navistar block thats priced right, BUY IT :)
Missy