Melling Oil Pump Interference - BEWARE
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Melling Oil Pump Interference - BEWARE
For anyone building their own engine and using the following:
Melling M155HV and ARP Main Studs
This condition may well apply to other applications as well.
Be sure to check for interference between the oil pump and the nut on the rear main cap.
When building my new 388 CID (LT1) I found that the oil pump sat on the rear main cap nut, but just barely. I couldn't tell by eye if it would prevent the pump from solidly seating against the rear main cap, but even a tiny gap at that spot would effect oil pressure. The pump would be sucking air.
My solution was to remove the pump, clamp it in my bench vise and grind off the edge of the pump (more like a bevel) to establish the needed clearance between the pump and the nut.
Just something else to check when installing the new Melling castings, since there's been so much contorversy about them.
Hope this helps.
Jake
Melling M155HV and ARP Main Studs
This condition may well apply to other applications as well.
Be sure to check for interference between the oil pump and the nut on the rear main cap.
When building my new 388 CID (LT1) I found that the oil pump sat on the rear main cap nut, but just barely. I couldn't tell by eye if it would prevent the pump from solidly seating against the rear main cap, but even a tiny gap at that spot would effect oil pressure. The pump would be sucking air.
My solution was to remove the pump, clamp it in my bench vise and grind off the edge of the pump (more like a bevel) to establish the needed clearance between the pump and the nut.
Just something else to check when installing the new Melling castings, since there's been so much contorversy about them.
Hope this helps.
Jake
Melting Slicks
Joined: Nov 2004
Posts: 2,799
Likes: 2
From: Cape Coral FL
Standard prep for use with main studs... We used to massage the pump nut when using an oil pump stud (BBC engines).
Bottom line is: any hand-assembled engine that deviates from stock MAY require extra engineering...
Clark Griswold said it best: "It's all part of the experience..."
Bottom line is: any hand-assembled engine that deviates from stock MAY require extra engineering...
Clark Griswold said it best: "It's all part of the experience..."
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
