SilverDeck
Well-known member
- Joined
- Jun 7, 2016
- Messages
- 481
It may be a long shot to post this request here on Garage Journal for help but I figured it is worth a try since I am finding a big fat nothing posted anywhere online to help answer my question. I'm trying to make sense of the casting production date codes that John Deere used on their aluminum deck 14 series and JX series walk-behind mowers.
The casting code is a round wheel-type marking that is found on the underside front center of the deck. For the purposes of this post I am attaching a picture of the date code from a JX75 deck with a production date listed on the serial number tag of 5/12/1998. The deck would have been cast some time prior to that date (assumedly). Around the outside of the code are what appear to be month/year number combinations 1-98, 2-98, 3-98 etc. Radial lines divide the wheel into sections or "compartments" and some of these are filled with a single raised dot. If the radial lines between months divide the wheel like I think they might, then there are four "compartments" for each month (are these quarters or each month???). On the second attached image I added some red lines to show how I think the wheel is divided up. I'm assuming that the wheel was placed in the casting die and that divots were added to the die as time went buy to help show the date when a particular deck was cast. What makes no sense to me is that there are some dots punched into the 12-98 section of the wheel when I know that this mower came off the production line sometime in May of 1998. Of course, I could be interpreting this all wrong. I'm hoping someone with experience in production casting can shed some light and help me interpret how to read these casting production codes. I feel like I'm looking at some sort of a Mayan calendar wheel and need a "Rosetta stone" to help me make sense of it. Can anybody help?
The casting code is a round wheel-type marking that is found on the underside front center of the deck. For the purposes of this post I am attaching a picture of the date code from a JX75 deck with a production date listed on the serial number tag of 5/12/1998. The deck would have been cast some time prior to that date (assumedly). Around the outside of the code are what appear to be month/year number combinations 1-98, 2-98, 3-98 etc. Radial lines divide the wheel into sections or "compartments" and some of these are filled with a single raised dot. If the radial lines between months divide the wheel like I think they might, then there are four "compartments" for each month (are these quarters or each month???). On the second attached image I added some red lines to show how I think the wheel is divided up. I'm assuming that the wheel was placed in the casting die and that divots were added to the die as time went buy to help show the date when a particular deck was cast. What makes no sense to me is that there are some dots punched into the 12-98 section of the wheel when I know that this mower came off the production line sometime in May of 1998. Of course, I could be interpreting this all wrong. I'm hoping someone with experience in production casting can shed some light and help me interpret how to read these casting production codes. I feel like I'm looking at some sort of a Mayan calendar wheel and need a "Rosetta stone" to help me make sense of it. Can anybody help?
