Certified Primary / STC vs. TSO vs. FAA PMA approved oil temp gauges?

[Johnbo]

I’m having a bit of confusion when looking at legal options to update an original oil temp gauge in an older Cessna 182.

I see many basic options available that are TSO’d and PMA approved but aside from a some full blown engine monitor packages there look to be only two options claiming to be “certified primary gauges”: EI OPT-1 & Aerospace Logic’s gauge.

In order to be legal and serve as a primary instrument for oil temperature, what designation would the gauge need to have?

thx!

 

[Bell206]

to update an original oil temp gauge

what designation would the gauge need to have?

Would need a specific indicator P/N to give you a more precise answer. But in general it depends on how you define “update” an original gauge. If you want to replace the indicator with the same type indicator but newer version then either an OEM replacement indicator or a TSO or PMA replacement indicator is the route. Now if by “update” you mean you want to alter the installation with a different type/style indicator then you possibly stray into the STC realm.

 

[Clip4]

Yoi have to either use A. replacement gauge from Cessna, B. replacement with an STC for your aircraft, or C. get a field approval from the FAA for your proposed replacement.

 

[Johnbo]

Would need a specific indicator P/N to give you a more precise answer. But in general it depends on how you define “update” an original gauge. If you want to replace the indicator with the same type indicator but newer version then either an OEM replacement indicator or a TSO or PMA replacement indicator is the route. Now if by “update” you mean you want to alter the installation with a different type/style indicator then you possibly stray into the STC realm.

I don’t have a part number handy but I’m talking about the oil temp from a Cessna gauge cluster which is a capillary type.

thx!

 

[Bell206]

I’m talking about the oil temp from a Cessna gauge cluster which is a capillary type.

Unfortunately with the factory 6-pack indicator you're stuck with the Cessna/Stewart indicators unless you install one of the other options mentioned in your OP.

 

[Tom-D]

If this change is not a major alteration, simply have your A&P sign it off as such.
read FAR 43-A this does not state that it is.

 

[Johnbo]

If this change is not a major alteration, simply have your A&P sign it off as such.
read FAR 43-A this does not state that it is.

That section seems to deal with scope of work and not individual component selection criteria unless I missed something.

 

[Checkout_my_Six]

IMHO....required equipment is part of the TC and not a minor alteration.So, it either needs to be replaced with the OEM part number, TSO equivalent, or PMA.....or STC'd part.

 

[Tom-D]

show me a TC that dictates make and model specific oil pressure gouge.

the TC may say oil pressure gauge is required, but it won't say witch part number.

 

[Checkout_my_Six]

show me a TC that dictates make and model specific oil pressure gouge.

the TC may say oil pressure gauge is required, but it won't say witch part number.

THE IPC....is part of the data.

 

[Bell206]

show me a TC that dictates make and model specific oil pressure gouge.

FYI: Part of every type certificate is the type design. Part of every type design are drawings and specifications that define the type design configuration and features. Part of these drawings and specifications are detailed listings of individual parts. One of these detailed parts listings is the aircraft parts catalog.

If the oil temperature indicator is listed in the 182 parts catalog, it is part of the aircraft type design, or as noted, part of the aircraft type certificate. Simple.

So it begs the question, if you believe the type certificate does not dictate the specific make and model of the engine oil [temperature] indicator, how do you know an aircraft conforms when you sign off an aircraft as airworthy?

 

[Tom-D]

So it begs the question,

Simple, FAR 43-A dictates what a major or minor alteration is. the oil pressure gauge is not listed as a major, so it is a simple paper work to do the change.
We as A&Ps are allowed to do minor alterations.
You should know know this.

 

[Bell206]

You should know know this.

Ha. What I do know is you still can't seem to answer the question posted.

the oil pressure gauge is not listed as a major

Really? So how do you define this 43 App A requirement?
(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.

 

[Tom-D]

Ha. What I do know is you still can't seem to answer the question posted.

Really? So how do you define this 43 App A requirement?
(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.

The question you continue to avoid, is these can be changed.

Did you see any indication systems listed?

 

[Tom-D]

the original poster should contact FSDO, and inquire as to how the indicator can be changed.
Their A&PIA should get involved Rather getting in to a pi$$ contest here.

See ya

 

[Matthew Rogers]

Ha. What I do know is you still can't seem to answer the question posted.

Really? So how do you define this 43 App A requirement?
(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.

I would say that there is no "change to the basic design of an oil system" to substitute one capillary oil gauge for another capillary oil gauge. What "change" would you see, other than a different part number? If you wanted to add new oil piping, route the lines in a different way, change the capillary style gauge to another type of gauge, etc. I could see calling it a "change to the basic design".

 

[Bell206]

to substitute one capillary oil gauge for another capillary oil gauge.

Not following your comment. What post are you referring to? Where is a 2nd "capillary oil gauge" mentioned? If the OEM Stewart "capillary oil gauge" is replaced with an electrical indicator are you stating this is not a "change to the basic design of an oil system?"

 

[Bell206]

The question you continue to avoid, is these can be changed.

Rather getting in to a pi$$ contest here.

Never said they couldn't be changed and gave examples. You said in Post #9 the type certificate doesn't specify which oil temp indicator to use. It does and I followed up that comment with a question to you, which you failed to answer, as usual. Then you stated a oil temp indicator alteration is not a major per Part 43. Which I followed up with a 2nd question to you which you failed to answer as well. So the only pizzin contest here is between you, yourself, and you. It is what it is.

 

[JAWS]

the TC may say oil pressure gauge is required, but it won't say witch part number.

The TC may also say wings are required, but it won't say which part number either!

 

[JAWS]

What make and model and year is the OP inquiring about?

If the gauge is replaceable, why not just replace with a new or serviceable part?