04-01-2011, 04:26 PM
58mm of Bliss
Join Date: Jul 2003
My Ride: 330i, 330Ci
M54 Oil Pump solution
After years of hearing about this oil pump solution for the M54, I finally ordered one to try on my 330i street car.
What is the problem with the M54 oil pump? The M54, and more notoriously the M54B30, seems to vibrate the oil pump nut off when rev'd above 6000 RPM. The more time you spend over 6k, the sooner the oil pump nut seems to come loose, which is followed by the oil pump sprocket coming off, which causes a total loss of oil pressure. (By by engine)
Here's a view of a stock oil pump without the sprocket installed:
The most common solution seems to be to weld the oil pump nut (OPN) on to keep it from vibrating off....even tough the nut is a reverse thread. While this works in the short term, eventually the shaft that the sprocket and nut have been welded to fails, (It literally shears off where it holds the sprocket) and the engine looses oil pressure. Here is an example of how this welding is done:
And the back side of the sprocket:
Another solution that many try is from VAC Motorsports for $200. They offer a kit with a new sprocket and oil pump shaft that must be pressed into the existing oil pump housing. Here's the kit:
Here the VAC Motorsports shaft has been pressed into the oil pump housing:
And all buttoned up:
Note that the bolt is a reverse threaded, and was installed to VAC's specified torque, and additionally we added Loctite Red to the threads.
I would love to report that this simple solution works, but it didn't in my engine. When the engine was torn down after approximately 80hrs or run time, I found the bolt loose to the touch, and the sprocket somewhat wobbly on the shaft. Based on what I found, I would say that it was just a matter of time on my engine before the oil pump drive sprocket came off. I have also heard from numberous other people that have installed this kit, on M54s, M52s, and S52s, and have had oil pump failures. It may allow the oil pump to last a little bit longer than the OEM piece, but eventually it fails.
So this left 2 solutions:
- Install the BMW Motorsport oil pump system for M54s at a cost of $3000
- Install a dry sump system at a cost of well over $6000 to do it correctly
Most people at seeing these prices seem to get the VAC kit and hope for the best. For me, this just isn't an option I would be comfortable with.
I decided to try a solution that Greg Smith ran on his car, and isn't commercially available, but if you ask nice he can source one for you. The price is more than the VAC Motorsports solution, but much less than the BMW Motorsports solution. What you get is a completely new OEM oil pump housing and internals, with a specially machined drive shaft and sprocket. I would say most of the cost is in starting with a brand new oil pump core, but I'm not complaining. This is one very nicely put together oil pump package:
Taking the sprocket off, we can see what makes this solution so special:
Yes, that's all one solid machined piece that the sprocket bolts to:
From a piece of mind perspective, I think this solution is a bargain.