[JAG]

Hi to all!

I am a new guy to the club. I have an overheating alarm problem with my 4.3L Alpha One engine. I have checked as follows:
Both water pumps OK
Risers and flappers OK
Thermostat seems OK

I hope someone can help me troubleshoot the overheating or electrical problem? Could I have a problem with the temperature sensors? Are they located below the thermostat? Please help!

Thanks,
JAG

[Jester]

If all else fails, it could be the impeller is worn and not drawing enough water into the engine. It’ has happened to me, replaced the impeller and not problem since.
You did not mention what year it is. It may be the original impeller .
Does it have a heat indictor?
Another thing to check is your fluid level for the out drive.
Some of the reservoirs have a float with an alarm.
If the fluid id low the alarm will go off.

[mikeyt]

You should buy a service manual or become a contributing member here at this site to gain access to those manuals.

Here's a link to the alarm codes: Mercruiser Warning System & Beep Codes