Is there supposed to be a check valve in OEM oil filters or the oil filter mount for a late M103 engine? If there is, it isn't working for me.

TIA,
Bud

what do you mean its not working for you?
the filters with a check valve(flap) still spill oil when you change the filter.

What brand of oil filter are you using?

Mann, Hengst; Mahle-Knecht are OEM for the 103 motor + what the dealer might sell. Have read here that a French outfit now makes MB oil filters(dealer that is) and that they are junk.

I have used Hengst, Bosch and Mann. The ones I get from a dealer are Mann. The Bosch is identical to Mann but it's made in the U.S.

Hi,

I just bought a filter from the local dealer as I needed it now vs. buying it online. They first brought out one of the new smaller filters and I asked about the older and much larger filter.

They brought out an older one and I asked them which they would use. I then said don't answer that question:-)

I took the older one made by Knecht.

I hope Knecht keeps on making these larger ones.

Regards,

Until recently, I've bought my filters from MB dealers. They always seemed to be made by Mann.

I recently bought filters from a supplier used by a lot of MB Club members. I bought one Knecht and one Bosch. The Bosch was identical to the Mann filters I had been using and it was BIGGER than the Knecht. The Knecht has 6 smaller holes and the Mann/Bosch have 4 larger holes.

Back to my original question, I wonder if the check valve is actually in the filter mount rather than the filter.

That's why I posted this question.

i'm assuming that you mean the valve that prevents the filter from draining out. its in the filter. mercedes did change it to a smaller filter.

The OEM filters have two valves. One is the rubber diaphram type anti-drainback valve, and the other is the filter relief valve in the center of the filter. The later opens in the event that the filter becomes clogged. Don't know the spec, but on most engines it's about 10 psi, and on most engines the valve is in the filter pad, not the filter itself.

I have an inventory of Bosch 72165 filters which have both valves. A few weeks ago when I was at Autozone I noticed they had a Bosch filter for the M103 engines, but it was a different number and didn't have the bypass valve !!!???

Duke