300d bordon tube oil pressure
 

my 85 300D oil pressure bordon tube leaks,, I have a 85 300 sd instrument cluster ,,,and it has the oil pressure sender w/ elec guage,,, how impossible is it to modify my cluster to include the sender and meter movement.... i have it appart and am evaluating what to do... yea the clock and the odometer are functionless also....

also it seems my injector pump diaphram is shot wont hold a vacume... how hard is that to replace also ,, have numerous vac leakes standard stuff for some... right now its a spare project and am determined to make it the diesel backup that I need. Thank you for your consideration

I just changed out my oil gauge from my 83 300D 2 weeks ago. Link below. It is much easy if to replace the section with the oil, temp and tank level gauges with one from JY. I ended up replacing the oil pressure gauge only, it is very fiddly but can be done. You need small plyers and a small angled screw driver.

I also took a complete section from a JY. It is a 79 300D model and it is a direct fit. I did not use it at the end as it has an aluminum circular cover in the middle which I do not like. I will sell it dirt cheap if you want it. Just PM me.

http://www.peachparts.com/shopforum/diesel-discussion/300337-engine-oil-under-dash-83-300d.html

ODO can be fixed. There is a lot of write up here. Clock can also be fixed. Just replace the 2 big capacitors on the PCB circuit board. Link below with a lot of MBZ repairs.

http://articles.mbz.org/instrument/renew/

You will need the electric sender from a 300SD to go with the electric gauge. The sender replaces the tube that runs from the base of the oil filter assembly to the mechanical gauge that came with your car. Then it's just a matter of running a new wire from the sender to the gauge.

Welcome to the forum David,
I had a leak like this at about 30k miles in my old 300D. The leak was from a crack in the solder at the joint of the bordon tube to the brass fitting. By just melting the joint with a soldering iron the problem was overcome.
The oil gauge on my w124 some times plays up ~ a bad electric connection probably. Have thought about trying to replace it with the one out of the old car.

If you change to an Electrical Oil Pressure Sending Unit you will also need to change the Plate at the Bottom Rear of the Oil Filter +Gasket to one that is drilled and tapped for the Sending Unit.

I only have a pic of one from my 300D that has a Mechanical Oil Pressure Gauge so the one in the pic is the not the correct one.