BD-12: Oil pressure gage doesn't work

[taylormarc]

After a 3 years hiatus I got the prop replaced, new exhaust system and did the annual + ADs. I also became an A&P in the meantime which helps. Now I have a question... I started it but oil pressure was 0 even if the oil was at the proper level. The previous owner told me to inject fresh oil at the oil pressure intake if it's help a while without flying which I did and also I also put oil in the oil pressure line. Obvious reason is the oil pressure gage failed but possible to test this? Otherwise maybe more oil to inject in that oil pressure point?

[mike lutz]

Sounds like your pump lost its prime. Pick the tail up and set it on a stool or something that would somewhere close to being level, then unscrew the oil temp. bulb out of the back of the screen. Take a small pump oil can filled with engine oil and pump oil into the back of the screen cavity. Reinstall the temp bulb and lower tail back to the ground and I think you will get oil pressure when you start it. Some times these little engines loose there prime after setting for awhile. This is due to the gears and case cover starting to get worn. Hope this works for you.

[Robert Lees]

Is it possible that you need to prime the oil pump in the engine? I did this as a precaution after a 6-year rebuild.

Remove the oil screen, raise the tail as high as possible; inject oil (using an oil can) into the housing...this allows oil to drain into the oil pump.
Lower the tail, refit the oil screen (don't forget the gasket) and fire it up.

Pictures:

Prior to the first engine run, I hold up the tail while John injects oil into the oil temperature bulb housing, to prime the pump...



...and it starts first swing!



Or it could be your gauge; get it tested and calibrated.

[taylormarc]

Is it possible that you need to prime the oil pump in the engine? I did this as a precaution after a 6-year rebuild.

Remove the oil screen, raise the tail as high as possible; inject oil (using an oil can) into the housing...this allows oil to drain into the oil pump.
Lower the tail, refit the oil screen (don't forget the gasket) and fire it up.

Pictures:

Prior to the first engine run, I hold up the tail while John injects oil into the oil temperature bulb housing, to prime the pump...



...and it starts first swing!



Or it could be your gauge; get it tested and calibrated.

How do you test it? maybe put some pressure in it? Just to show it indicates anything.

[3Dreaming]

With the proper fittings you could use a compression tester to test the gauge.

[PA1195]

Run solvent like spray brake cleaner through the pressure line to make sure it's open. Loosen the line at the engine and/or gauge to make sure there's oil pressure. Fill the oil line after cleaning to exclude air.

Gary

[taylormarc]

Run solvent like spray brake cleaner through the pressure line to make sure it's open. Loosen the line at the engine and/or gauge to make sure there's oil pressure. Fill the oil line after cleaning to exclude air.

Gary

I ran fresh oil through that line. My friend has an avionics repair shop and we did a static pressure test on it and nothing so therein lies the issue i.e it is clogged.
Any ideas to unclog it? Maybe some solvent or a way? Otherwise I am looking at a ew gage from Univair which is automotive (i.e $10 at any autozone) but FAA-PMA ($250).
Welcome to aviation I guess

[Robert Lees]

Get it fixed by your automotive shop. Reinstall and no-one is any the wiser, eh?

[PA1195]

Try to unclog the gauge with spray solvent? Fill and let sit then flush? See if gunk comes out?

Gary N36007

[Edwin Otha]

If it's the line, replace it. If the gauge is plugged you'll need to replace it. Stewart Warner makes some quality gauges used by many manufacturers. The original was probably a cross utilized gauge. Any company would go broke manufacturing an oil pressure gauge specifically for aviation.

[Scott]

Just in case-
by "static pressure test" do you mean he used a pitot-statis tester? Or did you actually put 50psi on the guage?

Could try warming it up, say in boiling water and see if whatever is congealed in there frees up.
S

[woodmw]

https://www.aircraftspruce.com/catal...clickkey=11518


Or go to Ebay and search "Rochester oil pressure gauge"

[Hank Jarrett]

Don't trash it. Pressure gauges can be fixed pretty easy (not so much temp gauges). Even if it is totally gone you can put new "guts" in the old case and repair it. If you don't want to repair it, someone here will take it off your hands (including me).

Hank

[Robert Lees]

and me!

[Robert Lees]

Temp gauge bulbs/lines can be fixed in the automotive world; seek the vintage car world. The likes of Morgan, Triumph Spitfire etc all use the same principle for oil temp gauges.
Rob