Just this weekend I was on the phone answering questions for a potential customer about the UAOS system, and his questions and problems he was having with his m96 led to me diagnosing his issue on the phone...and he verified it in video chat....

His M96 recently received some routine maintenance of the Vario-cam pads on the 5 chain version that was due.. but since the maintenance was performed he has been experiencing severe smoking on certain high-G turns while on the Track( even when running 1/2 qt low on oil)..and was asking if I thought the UAOS System would solve this problem....

I first asked if he has ever done a "blow-by" test on his engine to know the true health of the engine rings...he said no. Then I asked if the valve covers had been off anytime recently, he said YES !! So I asked him to verify that the return pumps were re-installed correctly...This is the pictures he sent me..

Bank 1 return pump should have 1-3 on the left ( crank side) with rotation arrow showing counter-clockwise

Bank 2 return pump should also have 4-6 on the left ( crank side) with rotation arrow showing clockwise

Even the UAOS System cannot overcome this situation..

So BOTH of his return pumps are installed backwards...This is the third m96 I have diagnosed in the last 2 months with return pumps incorrectly installed...The other two only had one return pump each installed incorrectly...

All three of these shops were well respected Indy shops, but there seems to be a pattern...If your M96 is not the most valuable car in the shop, it may get assigned to the least experienced Technician in the shop, and if he is not overseen closely by the Shop Foreman or Lead Tech, mistakes like this can/will happen...

So the moral of this story is "Trust but verify"...After having the return pumps R&R'd , look for your self that they are correctly orientated...It's easy and even YOU can do it....

 

Good info, Thanks for the heads up!
I suggest putting a paint mark from the edge of the scavenge pump onto the cil.head on bank 2 before dropping the car off at the workshop.
It can be done without jacking the car up and will ideally make the tech check the orientation of scavenge pump on bank 1 (with no paint mark) he refitted when he sees the paint mark on bank2.
Nonetheless I would jack the left rear up and mark bank 1 scavenge pump accordingly too.

 

In that case use a different color paint witness mark on each pump.

 

I am about to reinstall the oil pumps and was looking for the right orientation. Thank you. There isn’t a ton of info about it.

 

All good suggestions...anything to make these mistakes less frequent will help..

I hope I don't have to elaborate on how important having BOTH oil return pumps working is......

A Technician in a shop may be great with a Torque Wrench and have 10 years experience, but if those 10 years are primarily with Honda engines, or LS engines, or Nissan engines , or BMW engines , then mistakes like this can happen..

Someone that a Wrench doesn't even fit in their hands, but has hung out here in this forum for 10 years reading the Tech Threads has a better chance at not making this mistake...

The confusion can come from many things, such as" driver side/passenger side" (right hand drive vs left hand drive) ..." ROW /USA" ....Bank 1 vs Bank 2 ( Boxster vs 911) Left vs Right .." counter Clock-wise vs Clock-wise "........all can be misunderstood in certain circumstances/direction of view.... because nothing is "written in stone"..

But someone with 20 years of M96 experience and 30 40 50 years of engine experience would never make this mistake..