Oil Pressure Gauge 1985 300CD

[ArkyDoodle]

Recently I had an engine swap performed on my '85 300CD.....The oil pressure line to the OP gauge wasn't hooked up....When they changed the engine it came from a later 300SD which had an electric oil pressure sending unit instead of the straight pressurized oil line to the gauge (like it did originally)......Now the oil line will screw into the hole (where the 300SD's oil pressure sending unit was) but never "bottoms out" --- the oil line is never actually seated (you can push the tube in after it's completely threaded which allows for oil to get around the tube)......SoooOOOOooo at this point, I've either gotta find an adapter which will convert the existing "thru" threads" from the 300SD to a bottom-seated thread or change to an electrical oil pressure gauge.....??

[techguy512]

I'd go electric. My bourdon tube leaked and made a hell of a mess. I had to buy a new gauge and replace all of my carpet.

You're much better off keeping the oil OUT of the passenger compartment.

[turbobenz]

if you want to do it right, swap a 123 oil filter housing on. i did the reverse of you

[lutzTD]

Originally Posted by techguy512

I'd go electric. My bourdon tube leaked and made a hell of a mess. I had to buy a new gauge and replace all of my carpet.

You're much better off keeping the oil OUT of the passenger compartment.

yep, replaced all carpet in my 300D because PO left this leaking.

[ArkyDoodle]

Sounds like I should keep the oil pressure sending unit and find an electric OP gauge......Can I use one from a 300SD or something? I'd like to keep the original "look" instead of hanging additional after-market things on it.....Any ideas?

[Diesel911]

I would swap the gauge for an electric one myself. But if you are set on using the mechanical gauge you might be able to change the plate that is on the bottom rear of the filter housing where that electric sending unit goes into and the turbo oil supplu banjo bolt goes into. If you have an manual try to locate a Pic and you will see what I am talking about.

[turbobenz]

Originally Posted by Diesel911

I would swap the gauge for an electric one myself. But if you are set on using the mechanical gauge you might be able to change the plate that is on the bottom rear of the filter housing where that electric sending unit goes into and the turbo oil supplu banjo bolt goes into. If you have an manual try to locate a Pic and you will see what I am talking about.

the plate is not interchangeable

and a w123 filter housing will not clear the steering box in a w126, but
im sure you can put a 126 housing on there. Dont mess with trying to get it to work by retrofiting it with weird crap, It doesnt work. Its so much easier to just swap the major parts

[turbobenz]

Originally Posted by ArkyDoodle

Recently I had an engine swap performed on my '85 300CD.....The oil pressure line to the OP gauge wasn't hooked up....When they changed the engine it came from a later 300SD which had an electric oil pressure sending unit instead of the straight pressurized oil line to the gauge (like it did originally)......Now the oil line will screw into the hole (where the 300SD's oil pressure sending unit was) but never "bottoms out" --- the oil line is never actually seated (you can push the tube in after it's completely threaded which allows for oil to get around the tube)......SoooOOOOooo at this point, I've either gotta find an adapter which will convert the existing "thru" threads" from the 300SD to a bottom-seated thread or change to an electrical oil pressure gauge.....??

what about stacking several crush washers ontop of each other to make up for the clearance, or just a really thick washer with crush washers on the insides. Personaly, Id just put a 123 housing on there. its not a big job. 2 oil cooler lines and 6 allen 6mm screws and a gasket

[ArkyDoodle]

Originally Posted by turbobenz

i did the reverse of you

What type of gauge did you use and how did you do it?