Oil Pressure Sensor Port

[agent4573]

I think I know the answer to this, but wanted confirmation. In attached picture, under the arrow that says "From cooler" there is an 1/8" NPT port that has a plug in it. Any chance you can use that port as the pickup point for your oil pressure?

EDIT: Ly-clone-ing 360.

[PhatRV]

There is a small oil port just to the rear of the #3 cylinder, next to the oil pressure regulator. This is where my oil pressure hose to the pressure sensor is attached.

[PhatRV]

The "5" in the picture is the oil pressure port.

[swjohnsey]

When I was at Fun n Sun I talked to the folks from Lycoming. You can use "5" or either of the other two on that oil gallery on the prop side of that flange.

[DanH]

Originally Posted by agent4573

In attached picture, under the arrow that says "From cooler" there is an 1/8" NPT port that has a plug in it. Any chance you can use that port as the pickup point for your oil pressure?

Yes, with a caveat. You will get a pressure indication. However, consider how both pressure and temperature vary throughout the system. I'd suggest using conventional measurement points for both, so the indications are consistent with the rest of the fleet.

[agent4573]

Originally Posted by DanH

Yes, with a caveat. You will get a pressure indication. However, consider how both pressure and temperature vary throughout the system. I'd suggest using conventional measurement points for both, so the indications are consistent with the rest of the fleet.

The engine builder put a 45 degree fitting in the conventional place and the angle doesn't work with the rest of the accessories and hose routings. Unfortunately, I think I need to pull the engine back off the plane to gain access to the fitting in order to rotate it. I'm also not positive it's a restrictor fitting, and removing it requires taking off the backup alternator for clearance as well. Basically just an overall pain in the butt. I know you're right, it's just an over sight on my part I'm trying to work around without having to pull the motor.

I'll look into the other ports on that side and see if they're more accessible.

[John Tierney]

My engine came with a 45-degree fitting on the oil pressure tap. I replaced the standard straight hose (for oil pressure) with a braided hose that has a 90-degree bend at the end, which allowed some more flexibility of accessories, particularly my PMAG.
The attached photo, from TS flightlines, shows a hose end similar to the one I used, but I think I got mine from Pegasus.

[jrs14855]

The Cessna 172's since the restart of production use the front port of the right gallery for oil pressure pickup. The pressure reading at that point will be 8-10 # less than at aft end.

[jrs14855]

Search What Lycoming won't tell you by Bill Marvel for some interesting information.

[Joe Jet]

Originally Posted by agent4573

I think I know the answer to this, but wanted confirmation. In attached picture, under the arrow that says "From cooler" there is an 1/8" NPT port that has a plug in it. Any chance you can use that port as the pickup point for your oil pressure?

EDIT: Ly-clone-ing 360.

Side note. Per some ipc's, you don't need the plunger if you have a vernatherm. The operator's manual shows the hose connections to and from the cooler and I see them
backwards a lot. There is also a pressure port forward of the number one cylinder and that's what the d2j model uses.