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Hemi Oil Pump

Bird 426

Bird 426

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Going through the Hemi engine in a car that I bought earlier this year. The oil pump is a HI Volume, but do not know what brand, only numbers on it are USA and 18. The rotors are rough from debris passing. What Melling pump should I get? The HV or HP? This is a street car, roller cam may be hyd or solid. Or, is there a rotor kit available.
 
I run either the stock replacement Melling or the HV Oil Pump. 440
 
If the HV is on there now why wouldn't you put another one on ?!?!
 
Maybe I should rephrase, not sure what I have, the rotor is larger than the stock M 63. It's a hair deeper than 1 1/8". Not sure which pump I have. Maybe the only difference between the HV and HP is spring pressure, same rotor.
 
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No, the rotor and impeller are thicker on the HV. You can see the difference just looking at the outside of the pump. By the HV and forget about it.

Should we even talk about cleaning up the pump passages with a die grinder before installing ?!?!

And ... I'm a little concerned about "debris passing". Have you investigated that at all ??

May be the time to post some pics.
 
Bird 426 said:
Going through the Hemi engine in a car that I bought earlier this year. The oil pump is a HI Volume, but do not know what brand, only numbers on it are USA and 18. The rotors are rough from debris passing. What Melling pump should I get? The HV or HP? This is a street car, roller cam may be hyd or solid. Or, is there a rotor kit available.
Click to expand...
There isn't a rebuild kit for the HV pump, only the standard pump. The USA and 18 are on a new Melling M-63HV that you would buy today. Just get another one. Don't throw the old one away. My guess is it works perfectly.
 
Yeah, it had 80 lbs of oil pressure the one time that I started it to move it, the rotors are just rough looking. I bought this car with a ladder bar torn off of the Dana. The guy was tired of spending money on it, or should I say his wife was. It's been a money pit, I thought that it was a restored old race car, it wasn't. That's on me for not looking closer. I just kept finding things, see pictures. Originally, I was just going to repaint the engine and oil pan, when I saw the oil pick up and the crazy balancing, decided to tear it down. It's got H-beam rods in it now , over 4 lbs difference, rebalanced. I'm just trying to straighten out a few little things. The block is at 70 over, it's had a rough life, plus battle scars. Wheel weight lead was found under the Mallory slugs. I will get the HV pump. She will clean up and do what I want her to do, till I decide to get a new block.
Thank you guys for answering!

20231120_192315.jpg


20231117_182223.jpg


20231117_161156.jpg
 
Since you're working on a Hemi, just buy a new HV pump. But for a low buck wedge engine rebuild, the factory service manual goes into detail about how to inspect the oil pumps.
 
I don't know, never saw that before. Took over 4 lbs out with different rods. Picture of the rod that I took out. Crank is a stock stroke, 4340 Eagle. Not my first choice, but it'll work.
Yes, ordered a HV pump from Summit.

20240319_151229.jpg
 
Cant imagine why that much weight would need to be added to the crank. Where did the debre that went through the pump come from if you know?
 
Not entirely sure. I know that a Modman intake was replaced with the now available Edelbrock. The engine was gone through 5 years earlier. So at least an intake change after the rebuild. Not sure who worked on it. Not exactly talking with the guy that I bought the car from, for a lot of reasons. Main bearings looked okay, the rod bearings were a little scarred up. Crank looks fine otherwise, it's standard. It just is what it is. With help, I will get it back together with a little TLC!
If I need further help along the way, I will ask.
Thanks again!
 
From just what I see of the crank I would conclude the rest of the motor to be a piece of ****. The first thought is someone took a bunch of junk rods and pistons to the balancer and said "do what it takes" to balance it. And you're seeing the end result. What other possible reason would there be for a ton of weight crudely welded into one throw and a humongous turd welded to the flywheel flange ?!?!?
 
Bird 426 said:
Yeah, it had 80 lbs of oil pressure the one time that I started it to move it, the rotors are just rough looking. I bought this car with a ladder bar torn off of the Dana. The guy was tired of spending money on it, or should I say his wife was. It's been a money pit, I thought that it was a restored old race car, it wasn't. That's on me for not looking closer. I just kept finding things, see pictures. Originally, I was just going to repaint the engine and oil pan, when I saw the oil pick up and the crazy balancing, decided to tear it down. It's got H-beam rods in it now , over 4 lbs difference, rebalanced. I'm just trying to straighten out a few little things. The block is at 70 over, it's had a rough life, plus battle scars. Wheel weight lead was found under the Mallory slugs. I will get the HV pump. She will clean up and do what I want her to do, till I decide to get a new block.
Thank you guys for answering!

View attachment 1720052



View attachment 1720054
Click to expand...
Wow. Never saw anything like that but then again in these days nothing seems to surprise me...
 
No disagreement here. That's only part of what I found. How about small 4-speed bearing retainer, large bearing retainer bellhousing, no filler ring/reducer? And, pilot bushing pushed into the crankshaft, the input shaft was floating! Am considering a Bill Mitchell Products aluminum block, maybe a stroker, but don't really need it for the street. I have a new set of Edelbrock JR heads. We'll see.
Take care guys.
 
If you ever plan to race it, I recommend NOT installing a HV pump. Go with a stock pump. The oil return passages on a 426 Hemi are very small and you can pump a tremendous amount of oil into the heads on a 1/4 mile pass with a HV pump. If your pan capacity isn’t adequate, you will be rebuilding the engine shortly. I recently bought a car cheap because this precise thing happened and the previous owner lunched his brand new Hemi on the third pass.

That said, don’t just blindly follow my advice (or anyone else): call up a race hemi engine builder you trust and get their input on this.
 
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I don't think it will ever run over 6000. I have a new stock oil pump and HV on order. It has an 8 qt pan. Looks like someone drilled these in the valley.

20240902_120802.jpg
 
The issue is oil drainback from the heads, not the lifter valley.

If you aren’t going to race the car, you shouldn’t have any issues with an HV pump.
 
Seeing all the issues.

I think a new reciprocating assy would be on the list.
 
If the block bore is +.070" , it has had it. One mishap, and it's a base for a coffee table.
 
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