2010 Mercruiser 8.2mag goes into limp mode

[joelger]

My boat accelerates perfectly but after a few moments, the alarm sounds and it goes in to limp mode. Unfortunately it is impossible to read the smartcraft information in the sun. It does tell me that it is in reduced power mode but doesnt tell my why. The only thing i notice is the oil TEMPERATURE shows at -47. As i recall i dont think that reading has worked in the past but im not certain. I checked the service manual and i cant fine an oil temp switch anywhere.
I do have the diacom software and i am going to give that a whirl hoping it gives me some more information.
Anyone have any thoughts on this?

 

[alldodge]

I do have the diacom software and i am going to give that a whirl hoping it gives me some more information.

Best way to find out what the issue is

 

[joelger]

A little history. I had to replace the starter and i removed the seawater intake hose to give me access. When i put it back together i didnt tighten the clamp. The boat was going into limp mode due to low seawater pressure. When i tightened the clamp and took the boat out, it went a little longer but then did the same thing. I figured i probably had a bad impeller. I removed the seawater pump and found that the seals for the air drainage system are not sealing well. If i block the inlet and blow into the outlet, air is coming out through the drain. Can these seals be replaced?

 

[joelger]

Well, update. I disassembled the air actuated drain part of the pump and found a paint chip lodged on the outlet side of the pump where it drains through the air actuated system. The steel tube that moves up and down when air is applied appears to have been painted and the paint is flaking off. Im not sure if they are manufactured with paint or if the pump had been rebuilt.
Im hoping this is what the problem is. Ill put it back together once i get the new impeller and we shall see.

 

[alldodge]

If pressure is low that would do it, but there should be a code