OEM Big Block Oil Pump

[SSing]

My day two project calls for a this Oil Pump but may be hard to find a nice OEM Hemi Oil Pump.
Question: Is there anything else that differs the Hemi Oil Pump from a regular BB Pump, than the Relief Spring? Guess not but you never know...
Thinking its easier to find a nice OEM BB Oil Pump and change the Relief Spring.
A after market HV Pump is not an option, since I have to cut more off the motor mount, than if I use a BB Pump.

 

[493 Mike]

Whatever pump you decide on, open it up and deburr/check clearances/clean.
Mike

 

[gkent]

That's not a stock pump. The plate between the pump and pblock and the pump cover are both Milodon pieces. The only stock item is the pump itself. And the oil pan for that unit would not be "stock" either. So just what are you trying to accomplish. As for that cast iron "standard" pump, they're a dime a dozen since they came on every big block made.

 

[SSing]

That's not a stock pump. The plate between the pump and pblock and the pump cover are both Milodon pieces. The only stock item is the pump itself. And the oil pan for that unit would not be "stock" either. So just what are you trying to accomplish. As for that cast iron "standard" pump, they're a dime a dozen since they came on every big block made.

You say pump is not stock. Pump is a stock BB Hemi pump. Pump cover and sandwich are part of Milodon dual oil line system. I have all of that including the oil pan, but wanted to make sure I don´t miss something regarding the pump it self. And where I live here in Sweden I´m not so sure there are a lot of fresh BB Oil Pumps laying...

 

[rickseeman]

What you have is the normal oiling system for a Super Stock Hemi for many decades. They still sell that pump today. It's a Melling M-63 HP (sometimes called a Hemi pump) which is a stock big block M-63 with a black (Hemi) spring in it. Then it has the Milodon top plate and the Milodon lower plate for dual line oiling. You may think you need to replace it just because, but it probably doesn't need replaced. They almost never give it up. You can buy the K-63 rebuild kit. It has new rotors, gaskets, o-rings and both the stock red spring and the black Hemi spring. That system takes the longest oil drive which is 7" from the tip to the bottom side of the gear. Milodon part number 21500 or if you have a roller cam 21520 has the bronze gear.

 

[gkent]

Believe me when I tell you - with that system the "pump" is the least of your worries. Pull that cover off and if its seen any sort of use its going to be scored to ****. THAT is what you should be worried about - not the factory pump.

 

[Bird 426]

Don't the Hemi pumps have a 1/2" pickup?

 

[rickseeman]

The Hemi block has a 1/2" pickup. The pump is the same except for the high pressure spring. He is using a dual line external oil pickup going straight to the pump bypassing the internal pickup.

 

[Dave6T4]

The Hemi block has a 1/2" pickup tube provision. Not the pump itself. I would put a mechanical gauge on the second oil pressure port at the back of the block, and see what pressure the pump is actually providing.

 

[gkent]

The Hemi block has a 1\2" pickup tube provision. Not the pump itself. I would put a mechanical gauge on the second oil pressure port at the back of the block, and see what pressure the pump is actually providing.

Why, he hasn't mentioned that he has a pressure issue.

 

[SSing]

What you have is the normal oiling system for a Super Stock Hemi for many decades. They still sell that pump today. It's a Melling M-63 HP (sometimes called a Hemi pump) which is a stock big block M-63 with a black (Hemi) spring in it. Then it has the Milodon top plate and the Milodon lower plate for dual line oiling. You may think you need to replace it just because, but it probably doesn't need replaced. They almost never give it up. You can buy the K-63 rebuild kit. It has new rotors, gaskets, o-rings and both the stock red spring and the black Hemi spring. That system takes the longest oil drive which is 7" from the tip to the bottom side of the gear. Milodon part number 21500 or if you have a roller cam 21520 has the bronze gear.

Yes, thank you.
Good to know if I can´t find a good OEM pump.

 

[SSing]

Believe me when I tell you - with that system the "pump" is the least of your worries. Pull that cover off and if its seen any sort of use its going to be scored to ****. THAT is what you should be worried about - not the factory pump.

Yes, Pump Cover actually has a very small groov. It can be machined? Right?

 

[SSing]

The Hemi block has a 1\2" pickup tube provision. Not the pump itself. I would put a mechanical gauge on the second oil pressure port at the back of the block, and see what pressure the pump is actually providing.

Yes, part of the package...

 

[gkent]

It can be machined? Right?

They were orininally "hard anodized". I'm not sure if machining will do any good. Prbably would be just as bad or worse in a very short time.

 

[rickseeman]

All of the used ones are going to have small grooves. I wouldn't machine it, but you can lay some 600 grit wet or day sandpaper on a sheet of glass with water flowing on it and very lightly slide it back and forth on there going in all four directions of the face, just to knock off any high spots. Very light pressure. I did that in one of my oil pump videos on YouTube.

 

[Dave6T4]

When I rebuild transmissions, I have a hard white honing stone, that I touch up oil pump rotors, input, output shafts, etc. with.

 

[Geoff 2]

Never heard of 'anodized' cast iron....

 

[rickseeman]

That Milodon top plate is hard anodized aluminum.