Decode these rod and main bearings ?

[stroker402]

Checking the rod and main bearings to see how they look. Everything looks great ! NICE Crank ! CAN ANYONE DECODE THE NUMBERS ON THESE MAIN AND ROD BEARINGS? Look to be all standard mopar bearings . here are 2 pics of the rod and main bearing numbers . the 466 number is the mains . This 273 commando engine suppose to have 70k original miles . Going to order up new cam , rod and main bearings along with piston rings .

 

[rustycowll69]

just a guess, 4 66 = april 1966 ?

 

[Charrlie_S]

I agree 4 66 is date. Not sure about the 500-, but it might mean 1/2 thousanth undersize. Chrysler did select fit bearings. I have some OEM bearings on the shelf for a slant six, that are .001 and .002 under.

 

[stroker402]

Thanks for your opinions guys ! I'm assuming that they are standard bearings being this engine has not been tampered with . No aftermarket bearings like clevite and others with their stamp on them . anyone know the journal sizes off hand for the stock crank? I was looking last night and didn't find any info yet.
Oh , another thing I noticed was the oem solid lifters had a deep groove cut out around the centers of the lifter. why that instead of a solid smooth side lifter ? Oiling ?
here is a pic of the lifter that was in the commando .

 

[Max1196]

4 - 66 is the date code , 500 is just a part #, yes that's how the oem mechanical lifters looked like (even in 413's look like that)
rods= 2.1240 to 2.1250
mains= 2.4995 to 2.5005

 

[toolmanmike]

Those are the stock lifters and are called "dumbell lifters" for the obvious reason.

 

[stroker402]

Those are the stock lifters and are called "dumbell lifters" for the obvious reason.

tmm >> does the deep groove allow oil to pass thru the lifter gallery from end to end then ? and solid smooth lifter does not allow oil to pass thru gallery ?

 

[RustyRatRod]

Why do you want to decode bearings? To see if they are original and standard? You don't go by the date code. You mic the crank with a micrometer. The factory was known for using under sized bearings right out of the gate. They are not always marked, either.

 

[stroker402]

Why do you want to decode bearings? To see if they are original and standard? You don't go by the date code. You mic the crank with a micrometer. The factory was known for using under sized bearings right out of the gate. They are not always marked, either.

Just trying to see if someone rebuilt this engine with aftermarket bearings .
Yes , will mic the crank journals next.

 

[Max1196]

You've obviously doing a thorough inspection, the bearings to be looking at for "condition" are the camshaft bushings, they're the ones that will be "delaminating" at the 50+ year mark! Take a look.

 

[pishta]

Dumb bell lifters. Truly solid lifters, not a hollow lifter with a rigid seat. The bands allowed oil to circulate past them just like the shallow bands on lifters today. I imagine the weight saved by making them like that may have reduced valve float? Used them in 6's too.

 

[stroker402]

Dumb bell lifters. Truly solid lifters, not a hollow lifter with a rigid seat. The bands allowed oil to circulate past them just like the shallow bands on lifters today. I imagine the weight saved by making them like that may have reduced valve float? Used them in 6's too.

Interesting article here >>>>>>>>>>>>>>>>>>
"Low oil pressure when hot " explains all about the "dumbbell "lifter .

 

[RustyRatRod]

Just trying to see if someone rebuilt this engine with aftermarket bearings .
Yes , will mic the crank journals next.

Gotchya.....wasnt tryin to be a smartass......I was trying to remind you the factory did use under size bearings so best to measure!

 

[pishta]

Interesting article here >>>>>>>>>>>>>>>>>>
"Low oil pressure when hot " explains all about the "dumbbell "lifter .

I dont think they were ever designed to be used with a .373 lift cam....bush em tall!