Man D2848 LE403 Oil Pressure Senders

Oil pressure reading low on the MAN display or SW (Stewart Warner) dash gauges?
MAN senders are from DanFoss.
Sometimes you can get the DF part number off of the sender, google it and save some bux.
SW senders and gauges from NAPA.

I still order my MAN parts from these kids.
They probably sold and installed your engine.

https://www.performancediesel.com

Here is the problem with VDO and DIY;
SW works one way, low resistances to high makes their gauges go up.
VDO by standard works bass ackwards, high resistances to low makes their gauges go up.
Oh, But here is the rub; VDO also makes SW compatible senders and gauges.

There are different ways to find witch way your VDO is set up;
Call Viking and ask what they used.
Find a part number on the gauge and search from that.
Call me back for the red-neck process.

Now that I'm typing, I think I have your problem figured out.
Just ran into this problem for another guy.
You typed a VDO gauge in the ER and the helm??
Dual gauges on the same sender is possible,, if you use a sender for two gauges.
Or, a dual gauge sender will miss read on a single gauge.
For either VDO or SW.

While your looking for gauge part numbers, Let me try to find the sender locations for your LE403s.
I'm on my boat but back in the compound tomorrow.
If our bud in Sardinia is watching, he may remember where they are from the top of his head.

Have you looked around the oil coolers for any wire connects yet?
My first guess where they are.

Peek under the right exhaust manifold. Oil cooler and oil pressure senders should be there.
Or, follow the hoses from the oil filters to where they attache to the engine. Should be same place.

Weighing anchor shortly. Looks like another nice & hot day on the St Johns river.

There are not many wires that go into a LE403 mechanical block.
These wires and plugs are probably covered with lots of engine paint.
The oil pump is to the flywheel/rear of the engine.
The Pressure relief valve is inside the pan, behind the oil cooler, where the oil filters or remote hoses are mounted.
Somewhere around there is the pressure sender. Probably more hiden by the exhaust manifold.
Can't be many wires on that side.
The starter and heater box (if equipment) are on the other side.
My manual gives me the resistance values for different pressure readings but not a picture of where that dam sender is at.

I recall only 2 sets of wires down there. Oil pressure and Pyro coupler.

I second what CR already mentioned, the gauge that's reading half is designed for single station application. Since your engine room remote gauges are reading normal the sender is working fine. BTW I have 2840's and they indicate 30-40 at idle and 60-80 at cruise warmed up. Readings are much higher cold.

Hello Lunderic
Do you have a manual or picture showing exactly where your pressure sender is located?
My thin manual collection does not show anything and my memory has lost it's slower brain cells (all are slow these days).

I can second what Lunderic said ref. the pressure readings in my boat, powered by the very same engines as per thread title.
And I would second also CR question to Lunderic (or anyone else, for that matter) about any manual showing the sender location.
In fact, I'm now onboard and I just tried to locate the bloody thing in flesh, with no success!
I was also thinking to find it in the area mentioned by CR, but there's nothing down there.
BTW, in my boat I've got the plain vanilla oil filters directly mounted with no remote kit, so I don't think anyone ever fiddled with the sender.
Besides, I have manuals showing a drawing of it, as well as its part number, but not the location, aaaarumph!

I have a similar issue with my port temp gauge/sender, more an intermittent connection issue. It seems the gauge panel sensors are different from the MAN system (such as it is in these completely mechanical units). The Manuals give zero info on location, pretty poor.

Trying to remember or find a past customers mechanical MAN near me.
Last mechanical V12 I worked on sold and left town.

Time for a call or e-mail to Texas with engine serial number.
https://www.performancediesel.com

There are two senders just forward and below the oil filter housings. There is a third in the rear (I believe that’s oil temperature sender for remote panel)

That is where they were on that mechanical V12 I used to work on.
However, the OP has remote oil filters.

I wonder if the senders were moved with the filter bases. Never noticed that before.

AND, you have an oil line/hose coming off of the filter base assembly,,, To a remote mechanical pressure gauge or to the turbo?
That could offer another way to find the senders, follow the turbo oil supply hose back to the engine. Sometimes mounted on the block at the same place.