Got a new Mercedes OEM pump for my 87 300d. I see that I have the option of using a dam style gasket or not. I have read many threads about this gasket. But I am still confused about which one to use.
From reading the previous threads it appears that the dam gasket was not OEM. As the metal cage must be removed to use it. Are there advantages to using the dam style gasket?
And if I go with the open style gasket, should I use the metal or fibrous one?

IIRC the dam gasket is specified for very early engines because of different lubricant streams. I forget the break number but it’s 4 digits - 00xxxx. It doesn’t matter for later engines but using at outline gasket let’s you keep the basket where you won’t lose it. I prefer metal gaskets that don’t require scraping when you replace them. I reuse the metal gasket with the same front cover and pump.

Sixto
98 E320s sedan and wagon
02 C320 wagon

So the early models did not have the basket/cage? I read that you can't use the dam gasket without removing the basket. That's what confuses me.
I should contact the dealer and see what info they have.

If you use the dam style gasket, the basket must be removed. You can use either gasket, but the outline style lets you leave the basket in place.

__________________
Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

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1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]

Correct - it’s basket and outline gasket or dam gasket. Here’s some info -



You can’t go wrong with a dam gasket. If you pull the vacuum pump and there’s a basket, 3 bolts removes it for storage. Or spend ~$10 to have an outline gasket on hand which is most likely what the original is.

Sixto
98 E320s sedan and wagon
02 C320 wagon

Thanks all for the input! Looks like there is no advantage to using a dam gasket unless required. I'll see what my engine number is and take it from there.