[Geeman]

As the title says, do the CHT spark plug style thermocouples go on the top or bottom plug, or does it matter? If this is a dumb question please take it easy on me.

 

[DEWATSON]

top

Put 'em on the top plugs.

 

[agirard7a]

Top?

With the engine mounted they are on the bottom
Top plugs are for primer.

 

[Ironflight]

I haven't used the spark-plug-ring type sensors since my Grumman days, but I recall trying them on both top and bottom over the years - no difference in sensing, and each had their pros and cons for ease of servicing. Unfortunately, either way you go, they are a pain compared to bayonet sensors that you don't have to fool with every time you remove and replace spark plugs.

Paul

 

[pilottangocharlie]

With the engine mounted they are on the bottom
Top plugs are for primer.

I could be mistaken here, but I think this post is referring to the bayonnet style CHT probe.

In the spark plug ring type installations I've seen they have always been on the top spark plug.

 

[Geeman]

Tops

Top it is. Thanks for input.