Melling Oil Pumps

Just inspected the main bearings in my 454 from my last project after 50 miles driving. Main#1 was perfect, #2 showed little wear, #3 showed slight babbit loss as did #4. #5 Thrust bearing was totally deystroyed.

On this build the crank mains journals were turned 20 and rods 10. Installed a melling high volume normal pressure pump during the build.

On cold start up had about 70PSI oil pressure. At operating temperature at idle had 52 PSI and while driving ~65-70PSI. I knew that was too high so called melling tech support. They said relief on HV normal pressure was set at 70 PSI:dodgy:.

Installed standard melling reg pressure, reg volume pump and got

45 PSI cold, 35 PSI hot idle, 45 driving 3400 RPM:dodgy:

I'm suspecting I got a HIGH VOLUME/HIGH PRESSURE that starved my journals for oil since the oil feeds from the front to the back and I'm using a stock pan with 5 quarts of oil.

Anyone have some suggestions

Just inspected the main bearings in my 454 from my last project after 50 miles driving. Main#1 was perfect, #2 showed little wear, #3 showed slight babbit loss as did #4. #5 Thrust bearing was totally deystroyed.

On this build the crank mains journals were turned 20 and rods 10. Installed a melling high volume normal pressure pump during the build.

On cold start up had about 70PSI oil pressure. At operating temperature at idle had 52 PSI and while driving ~65-70PSI. I knew that was too high so called melling tech support. They said relief on HV normal pressure was set at 70 PSI:dodgy:.

Installed standard melling reg pressure, reg volume pump and got

45 PSI cold, 35 PSI hot idle, 45 driving 3400 RPM:dodgy:

I'm suspecting I got a HIGH VOLUME/HIGH PRESSURE that starved my journals for oil since the oil feeds from the front to the back and I'm using a stock pan with 5 quarts of oil.

Anyone have some suggestions

Click to expand...

There may be other problems but, it is likely that the high volume pump evacuated the stock pan, the oil can not return fast enough to refill the sump and starved the bearings. You can not run a high volume pump with a stock capacity oil pan. Sorry you had problems. Chuck

Chuck,

I remember the restrictor kits for the Clevelands were necessary when you run a 80psi or greater presssure pump. Would that be an option for the BBC along with greater volume/capacity?

Ray

Just inspected the main bearings in my 454 from my last project after 50 miles driving. Main#1 was perfect, #2 showed little wear, #3 showed slight babbit loss as did #4. #5 Thrust bearing was totally deystroyed.

On this build the crank mains journals were turned 20 and rods 10. Installed a melling high volume normal pressure pump during the build.

On cold start up had about 70PSI oil pressure. At operating temperature at idle had 52 PSI and while driving ~65-70PSI. I knew that was too high so called melling tech support. They said relief on HV normal pressure was set at 70 PSI:dodgy:.

Installed standard melling reg pressure, reg volume pump and got

45 PSI cold, 35 PSI hot idle, 45 driving 3400 RPM:dodgy:

I'm suspecting I got a HIGH VOLUME/HIGH PRESSURE that starved my journals for oil since the oil feeds from the front to the back and I'm using a stock pan with 5 quarts of oil.

Anyone have some suggestions

Click to expand...

There may be other problems but, it is likely that the high volume pump evacuated the stock pan, the oil can not return fast enough to refill the sump and starved the bearings. You can not run a high volume pump with a stock capacity oil pan. Sorry you had problems. Chuck

Click to expand...

I'm suspecting I got a HIGH VOLUME/HIGH PRESSURE that starved my journals for oil since the oil feeds from the front to the back and I'm using a stock pan with 5 quarts of oil.

Anyone have some suggestions

Click to expand...

First, I'm confused as to what engine we are talking about here. Is it a 454 Chevy, or a stroke Ford engine?

The volume of oil is probably what did you in. Using a stock pan is a no-no with an HV pump. If you're using a stock pan, like posted above, you probably emptied the pan and starved the bearings for oil. I had this problem on the first 302 I rebuilt, the oil pressure would drop on left hand turns....

When you get this sorted, get yourself a high volume pan holding at least 7 quarts. I'm partial to Canton, I worked there as their engineer in the late 90's.....

I'm suspecting I got a HIGH VOLUME/HIGH PRESSURE that starved my journals for oil since the oil feeds from the front to the back and I'm using a stock pan with 5 quarts of oil.

Anyone have some suggestions

Click to expand...

First, I'm confused as to what engine we are talking about here. Is it a 454 Chevy, or a stroke Ford engine?

The volume of oil is probably what did you in. Using a stock pan is a no-no with an HV pump. If you're using a stock pan, like posted above, you probably emptied the pan and starved the bearings for oil. I had this problem on the first 302 I rebuilt, the oil pressure would drop on left hand turns....

When you get this sorted, get yourself a high volume pan holding at least 7 quarts. I'm partial to Canton, I worked there as their engineer in the late 90's.....

Click to expand...

This was in my 73 chevy.:shrug2:

yup..you need the big pan i bet...my cousin has a built trans am..pushing about 500hp...his first motor started knocking cause of the same thing...ate up the bottom end..specialy if you corner hard ....like hemi says up there all the oil will go to one side and the pump will go dry!!....he had to buy a nice big racing pan with baffles.

yup..you need the big pan i bet...my cousin has a built trans am..pushing about 500hp...his first motor started knocking cause of the same thing...ate up the bottom end..specialy if you corner hard ....like hemi says up there all the oil will go to one side and the pump will go dry!!....he had to buy a nice big racing pan with baffles.

Click to expand...

If that was the case. Shouldn't I have seen a drop in oil pressure at some point. Never saw it happen.

his just started knocking for no reason...he didnt see a loss of oil pressure..but like you..it was waaaay to high at first....he didnt even corner his hard..just didnt have anough oil for the high preformance pump...he got the big pan..fixed the bearings...and it was fine then...but not allways the case..but usualy bearings going out is bad oil..driving it while motor still cold...or no oil..lol

ooohh ps..one othere thing is could be!! some one could of broke something off in your crank oil holes..put any oil restrictors in there? i know of a case where a machine shop did that to a freind...and it messed his whole motor up...they broke a tap off in the oiling hole and cutt off oil too the rest of the bearings...could be it..it would give you very high oil pressure..and run fine till it starved the bearings from getting oil were its clogged on...so..some bearings would be fine..while otheres..destroyed...i would check that cranks oiling holes.

his just started knocking for no reason...he didnt see a loss of oil pressure..but like you..it was waaaay to high at first....he didnt even corner his hard..just didnt have anough oil for the high preformance pump...he got the big pan..fixed the bearings...and it was fine then...but not allways the case..but usualy bearings going out is bad oil..driving it while motor still cold...or no oil..lol

ooohh ps..one othere thing is could be!! some one could of broke something off in your crank oil holes..put any oil restrictors in there? i know of a case where a machine shop did that to a freind...and it messed his whole motor up...they broke a tap off in the oiling hole and cutt off oil too the rest of the bearings.

Click to expand...

No, I would hope my machinist and I have a good enough relationship that he would have said something. I appreciate everyones input and I'm going to chalk this( and about $400 to redo crank and new bearings )to my mistake::yourock::