Odd valve on my oil cooler.

[Hi-Tec]

Greetings all. My bobbed deuce came to me with this valve on the oil cooler. I've deduced that it's a stem relief valve but can not figure out what it would be for. I've searched and read countless articles and haven't seen anyone one. Any ideas?

 

[NDT]

I believe that is a sample port for oil analysis. That program came into being right at the end of the M35A2 service.

 

[Hi-Tec]

I believe that is a sample port for oil analysis. That program came into being right at the end of the M35A2 service.

Well that makes too much sense. I was planning on using it for that myself.

 

[HDN]

My A3 has one on the passenger side of the engine block that's pretty inaccessible, so I'm pretty jealous

Maybe I should try installing another one somewhere easier to get to...

 

[Hi-Tec]

Another oddity on mine is an old circulating coolant heater that no longer functions. It's teed into the coolant drain petcock on the block by the starter and run to the port on the water pump. I'm thinking that's a good place to plumb a coolant filter.