Melling oil pump
Melting Slicks
Joined: Mar 2005
Posts: 2,364
Likes: 1
From: Rugby North Dakota
Melling oil pump comes w/ a RED high pressure spring installed - Melling directions say that if you want LOWER pressure, you should install the BLUE spring in the pump prior to installing the pump on the engine
I left the RED spring in the Melling pump - at 3500 RPM on highway, I'm seeing 75 - 78 PSI oil pressure on the DIC; between 4800 - 5000 RPM (VERY BRIEFLY last night), the DIC showed oil pressure to hit 99 PSI
EDIT: NOT entirely sure it was 4,800 RPMS - Could have been but not sure - I watched closely today - see my post below
I do not think my oil pressure sender is bad, since oil pressure does not randomly fluctuate, and since the DIC reads 0 (zero) oil pressure PSI when the ignition is on, but the car is off.
Houston, do I have a problem????????????
I left the RED spring in the Melling pump - at 3500 RPM on highway, I'm seeing 75 - 78 PSI oil pressure on the DIC; between 4800 - 5000 RPM (VERY BRIEFLY last night), the DIC showed oil pressure to hit 99 PSI
EDIT: NOT entirely sure it was 4,800 RPMS - Could have been but not sure - I watched closely today - see my post below
I do not think my oil pressure sender is bad, since oil pressure does not randomly fluctuate, and since the DIC reads 0 (zero) oil pressure PSI when the ignition is on, but the car is off.
Houston, do I have a problem????????????
Last edited by 94legaleagle; Apr 9, 2007 at 06:41 PM.
Melting Slicks
Joined: Mar 2005
Posts: 2,364
Likes: 1
From: Rugby North Dakota
Bump for the nite crew's opinions
took a highway drive today -
2500 RPMS, 199 degree engine oil - pressure of 65 - 67 PSI on the DIC
3000 RPMs, 196-8 degree eng oil - pressure of 70-71 PSI on DIC
I definately do NOT believe that I have a faulty Oil Pressure Sending Unit
took a highway drive today -
2500 RPMS, 199 degree engine oil - pressure of 65 - 67 PSI on the DIC
3000 RPMs, 196-8 degree eng oil - pressure of 70-71 PSI on DIC
I definately do NOT believe that I have a faulty Oil Pressure Sending Unit
Burning Brakes
Joined: Nov 2004
Posts: 988
Likes: 4
From: Livermore CA
I have a Melling in my LS1 440 and I have 65 psi with the red spring at 4000rpm and 5-20 oil. My son installed a Melling in an 06 6L GMC with low miles on the stock engine, he used the lighter spring and he has 65 psi at 4000 rpm. I built my engine intensionally a touch looser than stock so the Melling with the high pressure spring fits the bill perfectly. On tight engines I would use the lighter spring. I like the high volume aspect of the pump, it is beneficial to use the lightest viscosity oil possible for several reasons if you can maintain pressure. The lighter the viscosity the more heat it can transfer and the more volume you can run through your engine also pulling more heat.
Melting Slicks
Joined: Mar 2005
Posts: 2,364
Likes: 1
From: Rugby North Dakota
If mine stayed at 65 PSI, I would not worry about it - I'm worried, and pretty much convinced I need to pull things apart and put in the BLUE spring, becuase my oil pressure keeps rising as the RPM's rise
Supporting Vendor
Joined: Jul 2003
Posts: 6,486
Likes: 2
From: http://www.mphparts.com 800-364-1975
I don't think you really need a Melling unless you're doing something fairly involved to the car -- adding turbos which suck out some of your oil pressure, new/forged motor with looser bearing clearances, etc. In my case which did both, the Melling pump with the spring it shipped with resulted in 40psi at idle. Just right, IMHO.
Safety Car
Joined: Jan 2005
Posts: 3,675
Likes: 58
From: Hayward (Bay Area) CA
Not hijacking... but speaking of Oil pumps.........what's the procedure? Does a LS6 (ported) pump work much better than a LS1 stock pump? How hard is it to change one on a stock engine?
