Oil Pressure Gage

[MoonlightVFR]

I want a fast response time for oil Pressure Gage Indication.

Do not want to wait 30-40 seconds until finally jumps up to indicate.

Any suggestions on restoring the prime on gage.

I could not find anything in parts manual or Maintenance.

What can I do?

[bagarre]

You should have an immediate indication of oil pressure. if you don't have pressure in 5 or 10 seconds, you should shut the engine down and investigate (per owners manual)

Purge your pressure lines with kerosene or something to clear them out.

Better yet, swap the copper lines with a flex hose to avoid work hardened copper failing in flight.

[gfeher]

Grady,

+1 what David said about replacing your copper oil pressure line (if you still have one) with a new flexible one. Aside from eliminating the copper hardening issue (which is a serious reason to change it), after I replaced my copper line with a flexible one, I noticed that my oil pressure jumps up on the guage more quickly - in about 1-2 sec on an average day.

[MoonlightVFR]

I am all for replacing old copper lines with modern flexible lines.

Is there a Kit?

Do I purchase fittings and the hose from a supply house like Aircraft Spruce and/or NAPA?

Regards

[gfeher]

Grady,

While you can make one up yourself if you have the skill, materials and an elusive No. 2 mandrel to do it, the easiest thing to do is just have Precision Hose make one up for you. You can order it over the phone. Tell them you are a TIC170A member. The guy I spoke to there when I ordered mine two years ago was familiar with the issue and easy to work with. Here is their contact info:

Precision Hose Technology, Inc.
2702-D North Sheridan Road, Tulsa, OK 74115
(800) 331-5946 or (918) 835-3660
http://www.aircrafthose.com

Here is the part number of the one they made up for me for my '52 170B with stock C-145-2 engine: Precision Hose Technology p/n 193000-2D0183 (19” hose assembly from Stratoflex 193-2 hose with straight -2 female flare aluminum fittings on both ends)

19" was the perfect length for my plane, but you should check to confirm it is the correct length for yours. Also check to confirm that the end fittings are correct for your plane. If you have a stock engine, they should be. Cost me about $50.

Edit: I forgot to mention. The above hose replaces the copper line from the firewall through-fitting to the engine, which is the one most susceptible to hardening due to engine vibration. The other line is from the gauge itself to the firewall through-fitting. Precision can make that hose up as well from the same materials; however, its length will depend on the location of your gauge in your panel.

[bagarre]

I ended up making a set.
I was able to make a #2 mandrel using an extra fitting and a 1/8th inch drill bit. Worked pretty good.

[gfeher]

Yea, I have the materials to make a similar #2 mandrel for the next time I need one. I just haven't gotten around to putting them together, not that it takes long. Unless someone has some experience making up hose sets, though, I hesitate to suggest that they should just make one up themselves.

[bagarre]

Yea, I have the materials to make a similar #2 mandrel for the next time I need one. I just haven't gotten around to putting them together, not that it takes long. Unless someone has some experience making up hose sets, though, I hesitate to suggest that they should just make one up themselves.

It's very easy to make a hose wrong and never know it. When I made new brake lines, I blew out quite a bit of rubber slivers from the old ones.
Buying them pre-made takes a lot of variables out of the equation for sure.

[DaveF]

I had a -2 size fuel pressure hose with a rubber sliver that acted like a check valve. The indicated fuel pressure would start ok, but gradually increase as pressure pulses and temperature increased the pressure on the gauge side of the "check valve". I took a long time and wasted some money figuring out what the problem was. I fixed it with a blast of shop air through the hose.