E30 with M10 - oil starvation problem

[Mirek E.]

Hi, can someone help me with oil pressure drops in my M10 engine?

E30 318i, some suspension mods, coilovers, poly bushings, nothing extra.
Engine is stock M10B18, running great, 2 years after rebuilt, no oil consuption etc. Oil pump was checked last summer, some wear was visible, but no scratches or bigger damage.
Only one mod is oil cooler with sandwitch plate with thermostat under the oil filter. Oil cooler is mounted between valance and radiator, in/out is upwards, so when I turn off engine, oil should stay in cooler...
I also have oil temp and oil pressure gauges. Temp and pressure senders are in sandwitch plate.

Now the problem.
First part
When car is parked on flat surface and I coldstart the engine, oil light come off immediately, but I can see how needle in oil pressure gauge flapping around 2 - 5 bar, this happening for about 30 seconds or if I increase rpms to 1500, needle stay at 5 bar and everything seems okay.
If I park the car on the hill with front end down and coldstart the engine, oil pressure immediately jump to 5 bar a stay there.

And second part.
If I enter right-hand corner in higher speed (yes, right-hand, not left-hand corner - I know BMW engines have/had problems with oil starvation in left-hand corners due to engine position/tilt) my pressure drop once or two times from 5 to 3 bar, when I exit the corner and going straight, everything looks normal. In left-hand corners there is no problem...

I had and idea of relocation the pressure sender from sandwitch plate into the head, where is the stock pressure switch, but oil pressure in sandwitch plate should be more accurate than in head, true?

Thanks for help and sorry for my english.

[Das Delfin]

sounds like you have an aftermarket oil cooler.. I'd remove that and see if your problem continues

[TobyB]

2 things I have seen-

1- the dipstick cut a hole in the pickup tube, right about oil level.
That wasn't good.

2- The o- ring popped out of the bypass tube on the front
of the evgine, letting it drain down quickly.

You might have pickup problems, from the sound of it....

t

[e30davie]

Is there any particular reason for the oil cooler?

What are the chances the pickup tube is coming loose and when the car is on an angle the loose bit is now under oil and thus isnt an issue.

[Mirek E.]

Without oil cooler I was able to reach 130°C after a few laps on our local track. And it's not good temp even for oils used in race engines. Now, with a cooler, I am on 90 degrees while highway cruise and around 100 - 105 degrees on track. Oil is standard 10w40, usually changed after trackday or after 5000kms (without trackday use).

Problem was here even before oil pump check last summer. I removed timing chain cover, chain and guides and replaced o-ring under the tube, o-ring between oil pump and tube is also new. Both are from bmw dealer.

Dipstick can't reach to the oil pick up, on E30, oil pump is in front of the engine and dipstick is on the side...

I probably try remove oil cooler and make short loop between ports on sandwich plate. I also had this idea...

[Mirek E.]

I forgot this thread.

So, here my resolusion.

I get rid of that sandwitch plate for oil cooler and bought oil filter head from S14. S14 has oil cooler with thermostat from stock. Also, in S14 oil filter head are two ports for senders. From stock, one is for temp gauge and second is for oil pressure light. But M10 has it's own oil pressure light switch in head, so now I had two extra ports for senders. With two thread adapters from M14x1.5 to 1/8NPT, I can screw in oil temp a pressure senders for my Prosport gauges. With two 90 degree fitings, I hooked up oil cooler.
With this, I solved problem with oil pressure bouncing after startup. Sandwitch plate caused it. After shut off, somewhere in oil cooling loop was created bubble and after restart, the bubble must go thru whole engine and made that oil pressure bounce.

Next was oil starvation in right-hand corners.
I added crank scrapper from IE, horizontal baffle from Massive and OEM vertical baffle for S14 pans. I welded two tabs in lower oil pan and bolted baffle with rubber flap.
After this, I can fly thru cornes and oil pressure stays high, without any drops. :)

So, this was my solution. It may help to someone. :)
Sorry if I made mistakes in text, english is a little difficult for me. :)

[Jaxx_]

Thank you for documenting the resolution, Mirek! I am currently considering how to manage oil pressure loss in long left corners as the oil runs up the side of the engine block.

During a short autocross course (40-80 seconds) my oil temperatures can hit 110C, which is right about the limit of what I would like to run. Higher, I'm sure, on a road course.

I previously had a sandwich adapter (cheap ebay adapter) and didn't love it--currently I have no cooler and just keep an eye on temperatures. I have just turboed the engine and now I have to reconsider. Your posts have made sure I don't go back to the sandwich!