Oil Pressure Guidance

[GAHorn]

OK, ...here's one anecdotal reference: "When they fitted the long engine oil lines, Lindbergh demanded to have them made out of 18-inch lengths, connected at the joints by a hose, so as not to break from vibrations."

http://www.google.com/url?sa=t&rct=j&q= ... 8465,d.b2I

One of the things Ev Cassagneres related to me was when he finally managed to wrangle a meeting with Mr. Lindbergh.
He (Ev) had taken along a copy of Lindbergh's book in the event he might have an opportunity to have Mr. Lindbergh autograph it...but lost his courage and reconsidered after coming into the mans' presence, as Ev came to the conclusion it was perhaps an audacious and impertinent request to make.
To his hidden, personal embarrassment and also to his delight, as he left and bade Mr. Lindbergh good-bye.... in his quiet and generous manner, Mr. Lindbergh gave him a personally signed copy.

(Anyone who has contemplated attendance at one of our TIC170A conventions might add to their contemplations that had they so chosen...they would have had the opportunity to meet and become friends with Ev Cassagneres, Lindbergh's biographer, as he personally attended every one he could. Sadly, he passed last year.
There are many fine folks of great resource and quiet fame who are our fellow Members, and attending convention is often a surprising opportunity to meet and become friends.)

[cessna170bdriver]

George, now I'm embarrassed. The name Ev Cassagneres is familiar, but I've been to every 170 convention you've been to and then some, and I don't recall meeting him...

On the oil line subject, I suspect that one segment of rubber hose between each location that the line is hard-tied to structure would be suffcient. As for me, the one-turn coil Cessna put in the copper oil line on my airplane has been sufficient to date.

[GAHorn]

I last saw him at the Benton Harbor convention, but he also made Kelowna and I think it was Wilmington where I first met him, but he was only there two days and did not stay for the dinner, wanting to beat the weather out of there.
He wasn't someone to seek attention.
He and I shared about half a dozen phone calls in 2010 over another matter, but those calls resulted in quite an insight to his relationship with Lindbergh. I always thought we should feature him as a speaker at one of our events.
I guess we waited too long.

[n2582d]

If the tube is clogged up with gunky oil the best solution is to replace the copper oil tube all together . This due to the age hardening of the copper tube. ... .

Back in 1970 the FAA issued AD 70-10-06 to replace the metal oil pressure line between the engine and the firewall on some C-172's with Lycoming engines. Interesting that they didn't include earlier O-300 powered C-172's. Probably because they don't shake as much! I've attached a pdf file of the Cessna Service Bulletins that correspond to that AD. I believe it was Sacramento Sky Ranch that suggested replacing the copper line with 3003-O aluminum but I can't find that reference now that they are out of business. Neal Wright has a good technical article on replacing the copper line with flexible hose on the C-120/140.

The attachment Oil Pressure Hose Service Letter.pdf is no longer available

I ran across this stainless steel/teflon hose while on one of my scrounging runs at Faeth Aircraft salvage yard. It's .086" ID and .203" OD. It appears to match Goodridge 600 series hose. This is the only hose I've found that will take -2 fittings -- the same size as the original copper tubing. (JIC fittings match AN fittings).

[DWood]

I ran across this stainless steel/teflon hose while on one of my scrounging runs at Faeth Aircraft salvage yard. It's .086" ID and .203" OD. It appears to match Goodridge Series 600 hose. This is the only hose I've found that will take -2 fittings -- the same size as the original copper tubing. (JIC fittings match AN fittings).

Gary:
I had Stratoflex Teflon -3 size hose made up with -2 fittings and it has worked well for several years.
You might try http://www.specialtyhose.com
Dan

[n2582d]

Thanks Dan, that looks like a cheaper option.

[FredMa]

A cheaper solution is to simply re-anneal the copper to remove any hardening and re-install the line. It can be done by baking part in your oven. Doesn't get much cheaper than that.

[n2582d]

Your oven is better than mine. From what I've read copper needs to be heated to at least 750 degrees for annealing.

[DaveF]

Your oven is better than mine. From what I've read copper needs to be heated to at least 750 degrees for annealing.

I disabled the self-clean lockout on my oven and bake pizza at 800F. 90 seconds.

Back on topic: Thanks for the -2 fittings on the -3 hose idea. I didn't know you could do that.

[FredMa]

A small gas oven should be able to do the trick. I was thinking along the lines of an RV propane oven. I have read that a propane torch could be used but don't know of anyone that has tried it before or if that is just internet lore. It could be tested easily enough.

[DWood]

Back on topic: Thanks for the -2 fittings on the -3 hose idea. I didn't know you could do that

Dave/ Gary:
I had the hose made in 2008 and I can't find the receipt which is weird because I usually keep everything. I did find a business card for Precision Hose Technology PHT, Inc in Tulsa, OK and I believe that is the company that made the hose. They will make up custom hoses, see web address below.

800-331-5946 or 918-835-3698

http://www.aircrafthose.com/hose_assemblies.html

[n2582d]

I had a feeling Gary would beat George to posting something official albeit for a 172, it might be as close as we get. George, got anything with 170 on it?

From page 29 of the 1952 Owner's Manual under "Cold Weather Operation":

Where the oil pressure gage is extremely slow in indicating pressure in cold weather it may be advisable to fill the pressure line to the gage with kerosene."

[ghostflyer]

How do you get your wife to allow you to bake something like a oil pressure hose in her oven. I wouldn’t even bring it into the kitchen Incase it dropped oil on the floor .the only privilege I have in the kitchen is emptying the dish washer.

[Bruce Fenstermacher]

(Large exhale noise)

Gary, I've been holding my breath since 2014 with your reference to kero in oil lines for a 172 and the thought it be OK for a 170, though at the time we had no "Official" wording on the matter. Of course, (holding my breath once again) the owners manual is not an approved document.

As for annealing the line, I'd start at one end and heat the line with a propane torch till cherry red and move down the line to the other end allowing the line to cool behind the cherry red area. But instead of doing this if I just manufactured a new copper line.

[gfeher]

Or just have Precision Hose Technology make up a new flex line. I replaced my firewall to engine copper line with PHT p/n 193000-2D0183 (19” long “end to end” from Stratoflex 193-2 hose with straight -2 female flare aluminum fittings on both ends). (You'll need to measure your plane and adjust the length as necessary.) Added a restrictor fitting at the same time. No kerosene. Just connected it up. Came up instantly and has worked great ever since. Hose from PHT was under $50 a few years ago if I remember correctly.