I was helping a friend do a service on a 04 T800 mixer. On the drain plug I found what looks to be a piece of cast iron. None of us here at the shop nor the two Cummins mechanics with "30 years a piece" can figure out where it came from, the motor is a Cummins ism. Any help would be much appreciated, even a place to start looking. Thank you.
On a piece like that with machined inner surface I would drop the pan and look for more parts and pieces. My thought is it came from top end, It's part of a boss structure and I can't remember anything in the front or rear structures that would contain something like that. Has that engine ever had the head removed or other major work? Truck Shop
L10-M11-ISM close to the same upstairs. Many many years ago I had a L10 that broke part of the rocker shaft holder. Its easy to pull the covers and have a look.
I'd be suspicious of cam followers.
Absolutely agree with rocker arm theory. Are there service records to look at. Someone may have performed a repair and left that bit to find its way down to the pan. BTW , does it have Jakes? It almost looks like the slave piston bore, a little. That would be a large casting with edges to break off. As I look closer , I think I see a snap ring groove, if so , I'd start at the Jakes. You kinda hafta since they're on the very top. Lol
Have found push rod heads, rocker arm nuts, pieces of feeler gauge over the years. The one SINGULAR scary part to find is cam bushing copper or copper/steel. That is BAD JuJu.