Thread size and pitch question - W123, W126 oil pressure sender sizes - Page 2 - PeachParts Mercedes-Benz Forum

macdoe · #16 03-18-2013, 01:59 PM

I made a mistake on the price for the second fitting. I bought 2 so it is actually closer to $16.

snowbrd84 · #17 03-18-2013, 02:33 PM

I would also love to know what that thread size is on the w126 oil pressure sender. I need to get a 90 deg angle fitting for my swap.

Dan Stokes · #18 03-18-2013, 03:45 PM

Got it. Mine ('84 OM617) is an M12X 1.5 pitch. But remember, that's a NON-TAPERED pipe thread so you'll need some sort of sealing washer and a flat spot on the base of the fitting for the washer to contact. The OF base, of course, already has a flat spot.

Our Parker store fixed me up with a M12-1/4F8OHGS which is a M12 X 1/4 tapered NPT adaptor. I then went to a 1/4X1/4 90* elbow and then you could use an adaptor back to a different metric size if needed. In my working days I would take a set-up like this down to our shop and get the guys to TIG the whole deal together to simplify and make it more compact - you could do this that way, too, but not required.

Dan

snowbrd84 · #19 03-18-2013, 04:18 PM

So it looks like this would work and I dont even have to drive to the parts store...

Auto Meter 2277 1/8" NPT to M12 x 1.5 Electric Temperature or Pressure Metric Adapter : Amazon.com : Automotive

snowbrd84 · #20 03-27-2013, 01:50 PM

So there is a much simpler (and cheaper) solution. I took the original MB oil pressure sender and grinded off the entire top part, basically leaving just the nut at the bottom. This left me with the M12x1.5 thread and an unthreaded opposite end. I then took a 1/8" npt tap and threaded the other end. I was then able to use a 1/8" npt 90 deg elbow and screw it onto that fitting and install on the oil filter housing. So no need to buy a $15-$20 m12x1.5 adapter fitting...

jusme · #21 06-02-2013, 02:18 PM

I ended up proposing an American solution to a European problem, ha. I used a metric adapter conversion kit for the engine side to terminate it a 1/8" NPT. On the cluster side, it was tougher. I couldn't find an adapter from the metric size on the cluster, so I just drilled it out with a 11/32" bit, then tapped it for a 1/8" NPT adapter and used a nylon 1/8" line. Done.