Pressurized mags on 231's?

[skeptic]

Do stock 231's have pressurized mags?  If not, can they be pressurized via STC?

[DonMuncy]

My 1982 231 has pressurized mags.

[jlunseth]

As does my 1981. I am pretty sure they are factory, I have been through the logs although it has been some years, and I have not seen a 337 to replace nonpressurized. But I really don't know. I can tell you they are practically a necessity if you fly high, high altitude miss is a problem if the pressurizaiton is not working properly.

[thinwing]

i think presurized mags are pretty much standard on any turbo charged aircraft...after 15 k or so the air loses about half of its dialectric characteristic and the spark jumps to ground inside the mag.The connectors we all see on our sparkplugs also pressurize by compressing the silacone rubber cone into the hollow plug body thus compressing the air inside when tightened.The larger body mags like the 1200 series bendix werent so altitude intolerant...Ive had those up to 17/19 k with no missing etc...

[skeptic]

Thanks.  I knew that all 252's had pressurized mags, but was not sure about the original 231's.  Sounds as though all the K models probably had them from Day 1.

[jlunseth]

The way to find out is to look at the Type Certificate. It is on the FAA website, and I believe also on the Mooney site. It will list the original equipment for the 231.