Ok let me tell the story lol
I picked up a running 74 360 2bbl 61K from a sportsman rv to replace my current 360 in my 87-D250. Motor now sitting on stand,i pulled intake and valve covers as i want to change it to the 4bbl intake. Looking over the lifters/cam/rockers etc looks good heck the valve springs are still colored red & blue. Gaskets look all original only thing i can see that's been replaced is water pump and thermostat housing had some clear silicone around it. Still have factory timing chain with the plastic covered cam gear. When i removed heads i noticed the head gasket looks original and has the pentastar on it.


Well ... when looking at the rod bearings i noticed on the caps there marked with the number in which cylinder they should go. Well they don't match up in the right spot for example #1 cyl has a #7 rod in it/#6 cyl has a #4 rod in it and so forth???

I pulled a main & rod bearing to see if they were replacements but i don't see and numbers that show it.
#1 Main bearing has AT-20 8 73 The Rod bearing has DA-49 5 73M

 

Has the pan been off before?
Was every thing Torqued down rite?
Had you started it to see if it was knocking before you took it apart?

 

pan looked as it has never been off it was running before i tore it down it sounded strong and was quiet no odd noises. Someone said the rod caps are marked like that from production and he had a engine with rods all marked with same number.
Also was told the #73 on bearings mean they are original to this 1975 engine.

 

That's 70s Mopar for ya, kleen it up an put it back together if the bearings look good.

 

I agree....

 

That's what i'm gunna do check torques of everything new gaskets oil pump/timing chain set. and fix one of my exh valves hopefully