Installing a HV Oil Pump

[threewood]

I have been running the stock pump on my 440 since 2016. At idle it has always been a bit on the low side, 8-10 psi. Off idle and up to 6k rpms it always had around 55psi. I wanted to see if I could improve upon those numbers.

I'm using a Melling M-63HV pump and a heavy duty Melling intermediate gear.

First step to replacement is to get the engine on TDC #1. By doing this, reassembly is much easier. After rotating toTDC, pull the cap and mark or take a picture where the rotor is pointing. Pull the distributor and note how the shaft is aligned. Mine was horizontal with the engine centerline. Rotate the shaft out with a screwdriver and/or magnet.

Next, remove the old filter and remove the 4 bolts holding the pump to the block. 3 shorter bolts and 1 long bolt. Remove the pump.

The HV pump is 2" tall and the standard pump is 1-3/4" tall. You will need longer bolts.

Stock bolt and longer bolt.

New bolts cut to length. 4-1/2" for the long bolt, 2-3/4" for the shorter bolts. The threaded pocket is pretty generous (1/2" to 5/8" deep) I measured thread length past the housing.

 

[threewood]

Clean gasket surface good. Gasket was installed dry, bolts torque to 35 lb/ft.

New shaft vs. old shaft. HD shaft is tapered.

The new shaft comes with a bushing but mine was in good shape so I re-used it. Shaft went in, got the orientation correct and reinstalled the distributor. Installed oil filter.

Upon start up I had 75psi of pressure. Sweet. After warming up it had dropped to about 20psi. Double what I had. There are probably excess clearances in the engine but it still runs good. Reset the timing to 20 initial/37 all in.

 

[pnora]

Is this with new oil? If so I will bet once that oil gets some run time you will see a PSI drop.

 

[Kern Dog]

His pressures with the High Volume pump match what I have seen. Oddly the readings of cold oil pressure with the 10 w 40 that I use REALLY drop off at fast idle when warm too. I'm getting around 20 there, just like the OP. Going from 75 to 20 seems extreme but that seems to be common. My readings were slightly higher with the flat tappet cam though. The roller that I switched to must bleed a bit more oil around the lifter bodies.
They say that bearing clearances can make a difference but the OP never mentioned his, nor the weight of oil he used.

 

[threewood]

Oil was changed last month. 10w30 Driven. Next change will be a 10w40 to see if there is a difference.

 

[Aron Gleason]

I run the same pump and can get up to 100 psi cold when warming up the car, that's when I rev it up. Normally I see 70 psi.

 

[turbine68rt]

They say that bearing clearances can make a difference but the OP never mentioned his, nor the weight of oil he used.

That, as well as type. Full groove mains vs. 180° can directly affect pressure.

 

[493 Mike]

I just wanted to ask why the intermediate shaft slot was installed perpendicular to the crank centerline instead of the normal parallel position?
Mike

 

[threewood]

I just wanted to ask why the intermediate shaft slot was installed perpendicular to the crank centerline instead of the normal parallel position?
Mike

Horizontal is parallel.

 

[threewood]

That, as well as type. Full groove mains vs. 180° can directly affect pressure.

I don't know what mains were put in when it was built, but idle pressure has always been around 10psi and always jump to 50-55 psi on the throttle.

 

[R413]

The 10 and 55 oil pressure is just fine. It will live a long life.

This 80-100 psi cold is not really what your engine needs, it just makes you feel better. More is not better.

I had a 390 ford with 6 psi at hot idle, and 45 on the freeway. The mechanic shop said it was fine, and it was just fine for decades.

 

[Aron Gleason]

Id rather have 80 psi of oil pressure than 10 or 20 at idle. Why do you think more oil pressure isn't good?

 

[vance.dykes]

Watch this video It's really informative and remember volume is more important than pressure. duck://player/1NKiH6IHyEE

 

[Aron Gleason]

Watch this video It's really informative and remember volume is more important than pressure. duck://player/1NKiH6IHyEE

Can't click on it

 

[gtxrt]

Id rather have 80 psi of oil pressure than 10 or 20 at idle. Why do you think more oil pressure isn't good?

I don't think more oil pressure isn't good but I don't think it is any better either on a mild street car. HV HP pumps can run the stock oil pan dry so be careful. does more oil pressure cause more oil leaks with the rear seal ? more pressure on the dist drive gear and oil pump drive ?

 

[OKDart]

Id rather have 80 psi of oil pressure than 10 or 20 at idle. Why do you think more oil pressure isn't good?

2 reasons: Cheaper oil filters have been known to explode, and intermediate shafts have been known to shear off.

 

[vance.dykes]

 

[vance.dykes]

Can't click on it

Think I got it for you this time

 

[Aron Gleason]

I don't think more oil pressure isn't good but I don't think it is any better either on a mild street car. HV HP pumps can run the stock oil pan dry so be careful. does more oil pressure cause more oil leaks with the rear seal ? more pressure on the dist drive gear and oil pump drive ?

I guess ive been lucky, I haven't had any oil leaks at the rear main seal.

 

[Aron Gleason]

2 reasons: Cheaper oil filters have been known to explode, and intermediate shafts have been known to shear off.

Never had that happen and ive ran 70-75 psi for 34 years same motor and same intermediate shaft.