#1 cylinder cooler than the rest

[colind3782]

I have a four cylinder 31hp Sole Mini 34. While running it today I dug out my infrared thermometer to see what the temps are like. Pointing it at the head by the injector mounts I was getting around 70°C on cylinders 2, 3 and 4 but #1 cylinder was noticeably cooler by up to 10°. What do you think would cause this and is it a problem? There is no smoke from the exhaust from unburnt fuel. Also, where is the best place to point the thermometer to get the engine temp?

 

[Boater Sam]

Which cylinder is closest to the cooled water inlet?
Do you think that this could be the reason?
Is the water at the front of the engine near #1 cylinder the place where the water comes in or goes out of the engine?

 

[colind3782]

Which cylinder is closest to the cooled water inlet?
Do you think that this could be the reason?
Is the water at the front of the engine near #1 cylinder the place where the water comes in or goes out of the engine?

That's a possible. The raw water does enter at the front.

 

[Boater Sam]

There you go!