Mystery part

[Klassic]

I pulled my m30 down and saw this sitting in the wash up tank. What is this and where did it come from?
Thank you in advance for your guidance.

 

[Socrates]

Unverified AI answer:

This looks like the locking plate from the camshaft spray bar (oil spray bar) on a BMW M30 engine. Why this matches:

• The shape: rounded on one side, flat on the other — identical to the spray-bar lock plates used on M30s.
• Two small holes — these align with the two banjo bolts that secure the spray bar.
• Thickness and finish also match the OEM steel lock plates.

What it does: On the M30, the camshaft oil spray bar is held in place by two banjo bolts. These plates sit under the bolts to prevent the bolts from backing out, which is a known problem on older M30 engines. Many M30 owners safety-wire the bolts, but the original factory solution was this two-hole banjo lock plate.

 

[eriknetherlands]

The banjo bolts of an oil spray bar don't have lock plates.
(If there were lock plates, more M30's would be alive today)

Ai b.s.

Can't think of another answer though.
Looks like a plastic piece?

 

[Coast Motor Werk]

View attachment 211461View attachment 211461
I pulled my m30 down and saw this sitting in the wash up tank. What is this and where did it come from?
Thank you in advance for your guidance.

Do you mind giving a little more information, material? size?

 

[Klassic]

It's made of steel, approximately 1mm thick. I'm wondering if it relates to the hydraulic timing chain tensioner?

 

[Klassic]

That AI answer sounds plausible but it's totally wrong. There's a great example of why you can't trust AI.

 

[Coast Motor Werk]

Not sure about the diameter but from what it looks like I would suggest looking at the oil filter bypass or the oil pump pressure valve. Both have a spring loaded valve that has a plate holding the spring similar to this.

 

[stphers]

Looks like the plate in the timing chain tensioner that allows the oil into it It is the piece that is down inside the bore
That's what I think

Thanks, Rick

 

[Klassic]

Thanks for the response to all. My first concern was that it was a restrictor that could be essential for oil distribution, i.e not allowing too much flow into some area. Anyway it doesn't look critical and the chain tensioner is going to be upgraded to a non hydraulic system.
Cheers.

 

[Socrates]

Agree that the AI answer is an hallucination. The other AI answer was that it’s a clothing button.