Broken Oil Pump Driveshaft

[J. Cower]

Okay, so it's a 71 SSP with a 904 and new 72 340. Sitting on the 340 is a RPM Performer Manifold and AVS2 carb. Stock 360 heads. Comp HE 268 cam. HV oil pump. Everything else is stock. Broke everything in great and had great oil pressure. On first road run being easy on everything I lost oil pressure. Brought it back and pulled dizzy to find a broken oil pump driveshaft. What would cause this?

 

[J. Cower]

Oh and oil pump turns freely still...

 

[J. Cower]

Broken one on the left. An old one for comparison on the right.

 

[Fran Blacker]

Milodon I believe sells ones with harden tips. High volume pump can break them.

 

[Dibbons]

Was the broken shaft a Mopar stock item or aftermarket?

 

[Bobzilla]

Not supposed to use the stock style intermediate shaft with high volume or high pressure oil pumps. Get the Mopar version with hardened shaft and it should be fine.

 

[Fran Blacker]

The steel gear. MP one may cheaper.
https://www.milodon.com/oil-system/components.php

https://www.summitracing.com/parts/dcc-3690715/overview/

 

[dvw]

I'd pull the pump apart and have a look. Cant tell how many times we've found small pieces of valve seal retaining rings in the pump. The better shafts have the shaft flared into the hex, not cut square.
Doug

 

[Mopars & Missiles]

...The better shafts have the shaft flared into the hex, not cut square.
Doug

This is what Doug is talking about.......

Neither of the shafts you show in your photo have the taper, they are the "old" style that tend to break.

 

[J. Cower]

Okay I'm hoping its just that then. I ordered a mopar performance one and I'm also hoping I didn't hurt the new motor any. Thanks for the help guys.

 

[threewood]

How tight was the bushing?

 

[moper]

You can't run the stock drive with the HV pumps. They are prone to break. Not sure if you replaced it, I always use the MP shaft pictured even with standard volume pumps, and run a new bushing with it.