Rock Hall
New Member
- Feb 18, 2006
- 163
- Boat Info
- 1989 Searay 220DA 5.7
- Engines
- Mercruiser 5.7 Alpha One Gen I
I've got an 89 220DA with a 5.7 Alpha One/Gen I
I noticed a few weeks ago that sometimes when I would accelerate over 3000rpm my alarm would sound. it would immediately stop as soon as I backed off. Thinking maybe my water pump was getting old, I replaced it this weekend. Took it back out and same thing. I run a low temp thermostat. 140 Deg I think. Under low load the gauge reads about 140. When I accelerate or run over 3000 rpm it goes to about 150 (this is a guess) the needle hardly moves. this is when the alarm goes off. It is my understanding that the alarm shouldnt sound till at least 180. is this right?
I notice 2 sending units above the seawater pump on the engine. is one for the gauge and one for the alarm? My next replacement is the sending unit if it is separate. it doesnt make much sense why the gauge reads 150 and the alarm is going off.
Any ideas?
Help?
Mark
I noticed a few weeks ago that sometimes when I would accelerate over 3000rpm my alarm would sound. it would immediately stop as soon as I backed off. Thinking maybe my water pump was getting old, I replaced it this weekend. Took it back out and same thing. I run a low temp thermostat. 140 Deg I think. Under low load the gauge reads about 140. When I accelerate or run over 3000 rpm it goes to about 150 (this is a guess) the needle hardly moves. this is when the alarm goes off. It is my understanding that the alarm shouldnt sound till at least 180. is this right?
I notice 2 sending units above the seawater pump on the engine. is one for the gauge and one for the alarm? My next replacement is the sending unit if it is separate. it doesnt make much sense why the gauge reads 150 and the alarm is going off.
Any ideas?
Help?
Mark