Rochester Oil Pressure Gage

[n7188u]

Hi fellow Canard Pilots,

My LongEZ has an oil pressure gauge that is going south, literally. It is indicating low by about 10-15 psi low.

I got a mechanical gauge, calibrated it and checked the pressure in the ground and it is fine and confirmed the low pressure indication.

The airplane has a Rochester 3050-54 gauge and 3060-00018 sender.

Now the question is how to determine what is bad since information on these gauges is very limited. It would be ideal to know the curve (pressure vs resistance of the sender). I did test both the gage and sender this weekend and got these values:

Gauge:
PSI>Ohm
25>44
60>92
80>107
100>140

Sender
PSI>Ohm
40>60
60>79
80>100

So my questions are:

1.- is there a way to determine which component is at fault?
2.- What can i use to replace the sender if it is bad? ASC does have the Mitchell senders and there is always the VDOs (the Rochester 3060-00018 is made by VDO but I have found no cross reference).

Thanks,
Chris Martin
N295JF
"Race 25"

[Joe Dubner]

Chris,

Answering your question #2 ...

I replaced my unreliable Rochester sender /AND/ gauge with ones from Van's Aircraft.  They required no physical modification of the panel or wiring.

Gauge part number: VOP100
Sender part number: IE 411K (it's a Stewart Warner 201359, also available at some auto part stores)

These parts are for a 240- to 33-ohm system (0-100 PSI) and are not interchangeable with the Rochester parts so they must be used together.

You might be able to pick up these items from a local RV-er for a song as many have replaced their round gauges with glass panel engine monitors.

--
Joe

[n7188u]

Thanks for the reply Joe.

That is an very good option. I believe that the Vans gages are the same as the ISS sold by Aircraft Spruce. interestingly they are the exact same price

The other option which seems like a good one is the Mitchell's gages, supposedly made in the USA. But I prefer the 270 sweep in the gages you recommended.

For now I went flying yesterday (1st flight after this annual) and it is indicating correctly again. I will still order parts and replace at next cowling removal since the plane is trying to tell me something

So, almost ready for RR.

Chris