The International Cessna^® 170 Association

Eric, SIL7701 appears to say the 13340-00 gage is approved for the American Champion series aircraft and must be field approved for others. Am I reading this correctly or is there something buried somewhere else. Thanks Walt

Walt, as I recall, that tidbit of information re: approval was why I was poking around on the Scott website to begin with. Then I discovered the warning about the adapter configuration & I guess I forgot all about the approval issue.
Yeah, that's the way I read it too, the Scott gauge is approved only for the Champion series and everything else (including the 170 series) requires a field approval. I'm not gonna sweat it, at the time of installation of the first Scott gauge my mechanic signed it off in my logbooks as a simple "replaced oil temp gauge p/n....." and that's good enough "basis of approval" for me.

Eric

What with the FSDOs all locked up and the FUZZ barricaded therin because "Al Qaeda" is after them, I doubt they're going to venture outside to check the oil pressure gauges in antique airplanes.

I'm with you Eric. I was just trying to see if I missed something. A fellow 170'er asked when I told him about the Scott replacement. His mechanic wouldn't do the replacement and is sending his out for repair again. Thanks

For posterity reasons and due to broken links, I am uploading SIL-7701 and a few pictures to this website.

It appears Scott was purchased by AVOX systems and Avox has been purchased by Zodiac Aerospace.

The last post on this subject is from 2005. Well it is now Nov., 2013, and I wanted to tell everyone the problem of mismatching the incorrect adapter nut and the oil temp bulb sensor still happens. And I have some new updated info to share.

My last flight in my C-170 showed an oil leak which is traced to the oil temp bulb assembly at the adapter nut. I thought at first my oil temp bulb assy. must be broken and leaking. But as I researched the operation of the gauge, I realized that since my gauge is still operating properly (indicating correctly) that the tube assy. must still be good. Then I found all this info on the flat vs. tapered flange issue. Wish I had known before. Now I know why I was getting a oil leak from that area that I couldn't stop. I am about to drain the oil and check my adapter nut compatability with my oil temp bulb. Hopefully, I haven't ruined it.
So I start looking for a new gauge. Well the gauges at Aircraft Spruce are NOT FAA approved. On the forum somewhere else, and it may have been a post on the 120/140 website I saw, says the existing Rochester oil temp gauge can no longer be repaired. Well that is incorrect. I found out about and called a company called Keystone Instruments (1-570-748-7083) in Lockhaven, PA. They told me they can in fact still repair the original gauge to new. You won't like the price, but if you are interested in maintaining originality and using FAA approved parts (I know, I know), this company may be the answer. There appears to be a wealth of knowledge at that company and you actually talk to humans who are pleasant and helpful. So as I take mine apart and make any necessary repairs, I'll post any problems or info I learn.

Steve

Well your California types are always laid back..... But when the manual says it is for experimental only, well just for my piece of mind I'll stay with approved parts if still available or serviceable. I knew there would be some chatter when I mentioned approved parts. But thanks very much for the reference you mentioned. I will certainly look it up!

Steve

Steve,

The Rochester gauges are the same as they were when Rochester made them for Cessna. There wasn't any approval for them then and there isn't now. The reason Scott/Rochester won't sell their products direct as OEM is they had a deal not to do so with Cessna. So they sell them and make no claim as to what they are.

Spruce and Wag are being more careful to label anything that they sell that doesn't have a PMA or meet some other standard as Experimental. It keeps the Feds at bay. But just because Spruce and Wag do this doesn't make the part experimental only.

Furthering Bruce's comments... The fact that SPRUCE sells them for "experimental only" is merely SPRUCE's statement as to their own liability assurances. Their opinion has NO official bearing on the applicability of parts as regards certificated aircraft, other than to state they provide no basis of approval for specific applications. The part applicability is the responsibility of the aircraft owner.

OUR basis of approval is the OEM identicality and the aforementioned Advisory Circular AC 23-27. This subject was presented at the Benton Harbor convention by Inspector Anderson of the Detroit FSDO.

Some of our members desperately need to find a different, more practical, mechanic or AI.

Ouch guys! I thought this forum was to be helpful to fellow 170 owners. EXCUSE me for trying to ensure I am complying with legalities. I am disappointed by the personal derrogatory comments. Forget I asked.

Aryana wrote:Where did you see a manual? I ordered one back in 2010 and it didn't come with any paperwork saying EXPERIMENTAL anywhere, but maybe things have changed.

The catalog states it is not for certified aircraft if you look in the tab for complete info or description. Although the face has been changed, the fit form and function are identical so most of the 170 guys are saying it is ok. I hope their insurance companies and the FAA agree. Whatever they wish to do with their aircraft is no business of mine. Chief aircraft, Univair and Spruce all sell a lot of product to the homebuilt/experimental market. You just have to be careful if you require an approved part that you know what you are getting. I order things from all these vendors quite frequently. My purpose was to point out that the original face can be put on the new non FAA approved gauge, the gauge calibrated, and the proper paperwork completed by the instrument repair facility which then makes it an FAA approved gauge according to the shop. Whether it helps or is worthless...hope it helps. Some others on this forum seem to think I am being too anal. They don't know me as they would never say that if they did.

Steve, it does not matter what the Spruce, Univair or who ever's catalog says a part is. They do not determine if a part is usable or not. The FARs do and in some cases the FARS even allow you to determine airworthiness of a part. It is nice that they don't claim any approval, but to say they are only for experimental aircraft is only their opinion and likely their lawyers.

No one has a problem with you discussing what is legal and what is not. There are a lot of facts and there are a lot of opinions and lots of factual opinions as to what is legal and what is not. Given 3 IA's you are likely to find 3 different opinions and even worse given 3 FAA inspectors or even entire FSDO's you will get 3 different opinions.

You need to determine to your satisfaction what you believe to be legal given prudent study of all the regulations. But likely your IA's opinion will trump yours unless you find an IA with like thinking. And that is what that quip about finding more practical mechanics or IA's was about. Thing is I don't recall you even saying what your mechanic or IA's opinion is.

If you think sending your gauge to a repair facility with a Rochester gauge (or they buy the new gauge) to have them replace the face into the Rochester gauge makes it a FAA approved part you are mistaken. It makes it a Rochester gauge with your face in it. No more or less approved.

and if the copper crush gasket leaks, it was probably tightened too much. for torque, last time I checked, TCM says something like ..... "oil tight". Lycoming has better recommendations...

Thanks Guys. Turns out it wasn't a mismatch between the adapter nut and the capillary bulb flange. Both had the flat faces but are not sealing properly as oil continues to come out of the back of the NPT fitting where the capillary line goes into the fitting. Gauge now out to be sent to instrument shop for eval. Probably will get a new capillary tube installed with all new fittings. Or a replacement gauge. The saga continues.