Has anyone ever had a replacement oil pump come with a hardened gear already installed on it?

My replacement is a Melling, and the gear is a dead ringer for the hardened oil pump gear I was going to replace it with. Can you tell by appearance wether a gear has been hardened, or not? I thought the hardenening process gave the gears a darker appearance?

Brian

_________________
Flyin' Brian

74 Duster, 225, rear-mounted blow through turbo at 12psi boost, street/strip car
"Sixy Beast"

The only way to know is to have the gear(s) Rockwell tested for hardness.
We have tested many gears over the years... they all looked alike but the hardness ratings went from a low of 16 Rc to a high of 34 Rc for the carborized gears. (case hardening)
DD

I think the one I got from Doc was darker for sure. But I believe it has a tiny "DD" engraved on one of the ends. Don't know if he did them all that way or not. I'm sure he chime in.

Rick

Sorry Doc , you posted while I was typing!

Rick

Thanks Doc and Rick for chiming in so quickly!

I will obviously not try to judge a gear by it's color ever again!

Doc, do you have a favorite type of puller you use to remove the oil pump gears?

Brian

_________________
Flyin' Brian

74 Duster, 225, rear-mounted blow through turbo at 12psi boost, street/strip car
"Sixy Beast"

The puller I use is a modified tie rod end puller.
If there is no Keyway, you can remove the cover and press (drive) the impeller shaft out of the gear.
DD

Thanks Doc!

Brian

_________________
Flyin' Brian

74 Duster, 225, rear-mounted blow through turbo at 12psi boost, street/strip car
"Sixy Beast"