Beta 16 - 20 Diesel Thermostat - Temperature

[Bigapple1]

Have a Beta 16.

1) The company has great manuals and and illustrated parts manual, however I have not been able to spot a photo of the orientation of the Thermostat. Does the spring/pellet need to be up, or down toward the block

2) I took the old thermostat out in the fall, recently put a new one in, I believe orienting the spring/pellet down. Yesterday ran the engine for 15 min or so, with laser thermometer, saw the temperature on the top side of the thermostat housing going to 220 degrees F +, and the temperature on the lower/block side in the 150+ range. Shut down engine. Is the thermostat possibly installed upside down?

3) What should the opening temperature be? What temperature should I be seeing at the top of the thermostat housing when the engine is warmed up normally?

[GordMay]

The deep end (Arrow C, spring end) of the thermostat always gets installed going towards, or into, the engine.
(Arrow A) in the photo is the new thermostat gasket on the new thermostat, make sure to always use a new thermostat gasket if your Factory Service Manual calls for one.

[GordMay]

[Bigapple1]

GordMay, thanks the the quick reply..

The dilemma is that the temperature of the top side of the thermostat housing was some 40 degrees hotter than the block side, and at 220F plus. I have included a photo of the Beta 16. The thermostat is housed in that center top casting that sez BETA. The casting is directly connected to the heat exchange/tank (upper right) - you can see the radiator cap.

I do believe I put the thermostat in with the spring/pellet down, towards the block. The question is that typically you would see the block water temperature being the hotter side, and as it comes up to the thermostat setting, opening to allow cooler fluid to circulate - not the top side much hotter than the block.

In all fairness, I do recall not checking the tank to see if it had gone empty (a lot of fluid to disappear), and of course the exchanger was quite hot at the time. When I get back to the boat in a couple of days (2 states away), I'll check that.

I'm still trying to find out what the set point of the Beta 16 thermostat is, and what the running temperature on the block side of the thermostat should be for that particular engine.

[FPNC]

Someone has made modifications to that engine. The barbed port on the forward end of the heat exchanger is not normal.

You need to take some photos of the heat exchanger and contact someone at Beta Marine. Have the engine ID number. It is *~stamped~* into the block just below the fuel injection pump. Cast numbers mean nothing.