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:



What's inside:




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:

1. Install the BMW Motorsport oil pump system for M54s at a cost of $3000
2. 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.

Wow that thing looks great. How much $ are we talking about here?

Originally Posted by secono330ci

Wow that thing looks great. How much $ are we talking about here?

PM vaio76109 (Greg's unrememberable screenname - I just had to look it up again)

Thanks for posting pics! I've seen pics, just not that detailed.

how hard is it to replace the oil pump on these cars when it is on jack stands?

Originally Posted by HighBoostin330

how hard is it to replace the oil pump on these cars when it is on jack stands?

Now I am no pro but it should be as simple as remving the oil pan and a few more nuts.

the issue is that you would have o drop the front subframe to get there.

Thanks for the great writeup as always PEI.

Originally Posted by HighBoostin330

how hard is it to replace the oil pump on these cars when it is on jack stands?

The biggest pain is the that you have to drop the front subframe: Disconnect steering shaft and hydraulic lines, disconnect the brakes, and drop the struts. You'll have to have an engine support from the top, as you'll be dropping the engine mounts as well. Pulling the pan and pump in comparison is pretty easy.

Originally Posted by secono330ci

Wow that thing looks great. How much $ are we talking about here?

I kind of screwed up taking the pictures, so they aren't as sharp as I usually like them to be...but the work on this pump is worth every penny.

Originally Posted by McSpeed

PM vaio76109 (Greg's unrememberable screenname - I just had to look it up again)

I know...6+ years and I still can't remember it.

Originally Posted by aggieE46

Thanks for posting pics! I've seen pics, just not that detailed.

You are welcome.

Originally Posted by mvrk10256

Thanks for the great writeup as always PEI.

Glad you enjoyed it. I hope it helps people make a more informed decision in this area.

Originally Posted by PEI330Ci

The biggest pain is the that you have to drop the front subframe: Disconnect steering shaft and hydraulic lines, disconnect the brakes, and drop the struts. You'll have to have an engine support from the top, as you'll be dropping the engine mounts as well. Pulling the pan and pump in comparison is pretty easy.

thanks for the info. you're just a wealth of knowledge!

now my next question is whether i want to do this myself or give it to a shop to do it.

You can do it. I've DIY'd my oil pan gasket in my garage (with a cheap hoist). It's very much a DIY if you have one.

Originally Posted by HighBoostin330

thanks for the info. you're just a wealth of knowledge!

now my next question is whether i want to do this myself or give it to a shop to do it.

Thanks for the information, I was considering the VAC update but this definitely seems to be a better alternative. For the moment I'm using an LED warning light for the oil pressure incase the nut does happen to come off.

I presume the lock-tite nuts on the later cars are still very much prone to this problem?

Originally Posted by MasterC17

I presume the lock-tite nuts on the later cars are still very much prone to this problem?

The two things the later cars have going for them:

• a different P/N vibration damper that lists a slightly wider range of harmonic damping frequencies - I posted pics in some thread around here in response to azzy's question about it
• a sprocket nut (aka OPN) with factory applied loctite

Do they make a difference? Although I can't recall a post about a newer car (IIRC 9/2003 onward) losing its sprocket, I doubt it. I think it's just a matter of time- tracktime that is. Really hanging out above the 6K mark is going to create wild crankshaft harmonics that will eventually loosen the nut or break the sprocket shaft. These are street cars and I guess BMW doesn't expect revving like that. When the harmonics get going your crankshaft starts to become much less a solid piece of forged steel and much more a really long tuning fork. Especially if you're making more power than stock and/or running a lightweight flywheel. The oil pump sprocket is chained to the crankshaft and gets abused by the thrashing harmonics. To address this nonsense I installed Greg's upgraded pump, an ATI Super Damper and stuck with the stock DMF when I replaced my clutch. The perceptible upshot is that now when I rev over 6K it's completely butter smooth (this is pretty much due to the Super Damper). Before, it was kind of angry-feeling. The more imperceptible upshot is total peace of mind about tracking it.

One simpler alternative might be replacing the stock vibration damper at a conservative interval - TxZHP04 did this and said it felt a lot smoother. I think older cars tend to see more OPN trouble primarily because their vibration dampers wear out and usually go unreplaced for years. The problem is that, like a bushing, they can look ok but not work well. Whatever the car's year, they're made of rubber and ~5 years is a reasonable street driving lifespan for them IMO. Infamous racer mrshelley replaces his vibration damper(s) after every 1-2 GA events(!). The more robust and better damping ATI Super Damper is rated for something like 5-10 years depending on how much track you're doing, but it's not allowed in some racing classes.

Can you get by tracking the car without the upgraded pump if your harmonic damping is good enough? Maybe. Time will tell. But if you're really hanging out above 6K regularly I wouldn't risk it myself.

Fwiw my OPN was on super tight after about 75K of spirited street driving including about 3K miles turboed. Did I rev above 6K much? Sure. Did I hang out there much? No.

Originally Posted by PEI330Ci

The biggest pain is the that you have to drop the front subframe: Disconnect steering shaft and hydraulic lines, disconnect the brakes, and drop the struts. You'll have to have an engine support from the top, as you'll be dropping the engine mounts as well. Pulling the pan and pump in comparison is pretty easy.

When I did it I didn't disconnect any hydraulic or brake lines or drop the struts. To get the subframe out I popped the control arm connections out of the wheel hubs, moved the steering rack forward, undid the lower motor mount nuts, undid the subframe bolts and voila. This was all per BMW TIS. Not easy at all either. And I wouldn't trust an engine hoist if you're leaving it over night- I used a screw jack under each motor mount to be safe.

That looks like a well thought out solution to the issue, opposed to a temporary fix!

Thanks for the post!!

Awesome info as usual Adam!

The harmonics is the real issue and only for the 3.0l motor. You can take the 2.8 or 2.5 and just safety wire the nut and you'll be set for what most people do.

I grenaded a motor this year just because it is seeing 6700 on the high banks of Daytona and 6900 when it runs in a draft. This is for at least 10 seconds per lap. After enough laps, the crank broke, the timing wheel exploded, the guide rail on the oil pump chain was broken and the oil pump chain shot all of the rollers out of it. On top of all of that, the harmonic balancer had rotated by about 60 degrees (the timing mark was that far off). In the series I run in, I'm limited by rpm is I like it or not. The N52 motors do not suffer from this problem.

This is the most extreme situation and I doubt any of you will ever see this. What usually happens, is the oil pump shaft shears off and the motor blows up (they can run for around 117 seconds without oil pressure).

I would suggest this oil pump shaft if you are going to do some racing with the car. As these cars get older and cheaper, people will start to track them. Thing is, what I learned 10 years ago, is finally coming around for everyone else.

If you are going to run occasional track days with a regular 330, then you are fine. If you are going to put some serious time on it (5 to 6 hours per weekend) then you might want to look at this option. Most people don't run their car on the track flat out for long periods of time. If you do, just beware of what can happen.

So the 2.5's are good? And why is this? Undersquare design?

how about a 2.5 that has the 330 crank in it?

Originally Posted by Iceman00

So the 2.5's are good? And why is this?

The M54B25 is oversquare so I guess something to do with its [cast construction, ]comparatively shallower crank bends and [perhaps] the resultant 'lower piston speed relative to engine speed' keep the harmonics from really going.

Originally Posted by jacobs323i

how about a 2.5 that has the 330 crank in it?

I'd say it's in the same boat as the 3.0 liter engine.

Originally Posted by mrshelley

If you are going to run occasional track days with a regular 330, then you are fine. If you are going to put some serious time on it (5 to 6 hours per weekend) then you might want to look at this option. Most people don't run their car on the track flat out for long periods of time. If you do, just beware of what can happen.

Great guideline^

Originally Posted by mrshelley

I grenaded a motor this year just because it is seeing 6700 on the high banks of Daytona and 6900 when it runs in a draft. This is for at least 10 seconds per lap. After enough laps, the crank broke, the timing wheel exploded, the guide rail on the oil pump chain was broken and the oil pump chain shot all of the rollers out of it. On top of all of that, the harmonic balancer had rotated by about 60 degrees (the timing mark was that far off). In the series I run in, I'm limited by rpm is I like it or not.

Wow, I didn't realize it could break that bad. I'm hoping if this ever does happen the nut just shears or falls off and I can still save the engine. I'll be shifting at 6200 for the time being.

I was going to go with this solution but don't think I need it. I track the car for 4-6 weekends per year. With my s/c kit and the twinscrew's low end torque, I really don't need to hang above 6k rpm too much. In fact, I think my car does best between 3.5k rpm to 6k rpm.

I've concluded from past threads, the Greg Smith solution is the only way to go if you're going to go through the time and expense to do this.