Temperature sensor on a Stella 4T

Stilts · Post by **Stilts** » Thu Sep 24, 2015 2:55 pm

About to rebuild my 150 cc 4T Stella/Star engine with the 165 kit and a new crank. Figured I might as well add a temperature sensor because of the nastiness I encountered in May with blowing a hole in my head. Yes yes, that "never happens" but it did. There's a first time for everything. What's the temperature ceiling I should be looking at once it's broken in with the 165 kit? I've got the Polini 22mm carb and the GPR exhuast already installed.

jimmbomb · Post by **jimmbomb** » Sat Sep 26, 2015 12:36 pm

I know that nobody here has answered your question yet, so I will suggest that you put the temperature sensor on one of your buddies 4t. And let him run it around until you get your rebuild done, then you will know what his temperatures are and that will get you close to what you need to know.
good luck

Stilts · Post by **Stilts** » Mon Sep 28, 2015 1:09 pm

jimmbomb wrote:I know that nobody here has answered your question yet, so I will suggest that you put the temperature sensor on one of your buddies 4t. And let him run it around until you get your rebuild done, then you will know what his temperatures are and that will get you close to what you need to know.
good luck

Good idea. Now to cajole the few people I know in the area with a 4T shifty to do just that!

Stilts · Post by **Stilts** » Mon Sep 28, 2015 1:11 pm

Speaking of the rebuild, we got the cases apart without a hitch and everything looks good inside. There was some metal gunk here and there, but all the gearing looked just fine and we're thinking that the metal came from the bearings. Still, after 13k, it looked just fine.

Now to wait for the new bearings. SHE WILL RUN SOON!

viney266 · Post by **viney266** » Mon Sep 28, 2015 2:13 pm

I have always used EGT on four strokes. The problem is the size of the probe on a small 4T engine. It needs to go a few inches down the exhaust pipe welded in. THAT would be perfect, but is more complex than a CHT ( but reacts much faster). The range you want on a EGT thermocouple is 1200-1300 with short trips to no more than 1450. I use these on supercharged cars to keep an eye on stuff.

The CHT is great on a 2T and should work well enough on a 4T if we can find the proper temp range. I don't know what that is on a Stella 4T.

Base readings on a stock one would be nice info to have.