[Mo]

Your temps were fine. I check mine regularly with infra-red
-head usually around 102 for me and hotter near plugs.
-manifold 200-300 range...that will be normal.
-block will initially read around 140 or so but once the engine is running for hours it will be around 160.
-block will be hotter around the crankcase vent where the tube comes out the the carb...normal.
-after hours of running I found my temp around the carb, down low on the block around 150.
-oil pan ( even took a shot at that) sit around 150 under hours of use....keep in mind that oil is constantly running through the engine.
-side of the engine near starter and water intake side is around 140 regardless.

So the temps are up on the water jacket /carb side about 10 to 20 degrees because that manifold is sitting right there warming everything. I ran my engine about 7 hrs straight twice, weekend before last. I was keeping an eye on things and all was good. I run RWC, no T stat.

I'd like to relay a quick note: when I'm motoring I sitting directly behind the helm. I am listening for the exiting exhaust water...it's automatic. I mentioned I run with no T stat and by-valve half open...the above temps reflect that configuration on my engine. Prior to getting an infra red thermometer I alway removed the steps and put my fingers on the head....if I could hold them there the engine was doing fine. Just something to keep in mind.

PS: 3 weeks ago I towed a O'Day 34 back to the club (yeah, another Diesel) and it was in the water all winter because I could see the rim of jungle beneath it. Tow lasted a couple of miles and I did take shot at the engine with the infra read as Odyssey proceeded on autopilot with our tow. I knew the O'Day was back there because I could only make 4.2 kts in pretty calm conditions. It was at this point I figured I'd check the engine temp as all the horsies were up and at it. Block wasn't over 145 degrees at that time.