1999 sx150txrx alarm and surging

[robaloroger]

I was out the other day with twin 99 sx150txrx and the alarm went off. I slowed down and looked at gauges but oil was fine and not overheating. 2 remote tanks were full and the 2 on the motor were full.Turned off port engine and alarm went off. I was already in the inlet heading in so I did not have far to go. starboard motor was accelerating fine when port motor was off. When I turned port motor on at idle starboard motor was in rpm reduction. Port motor was in rpm reduction when both motors running and when only port was running. Got home and ran on hose for a little with the rpms surging by 400-500 on port, same when pumping primer ball. starboard seems fine. I am going to swap gauges and take it out. Maybe gauge was not working properly? Is the alarm only for overheat/oil issue? Is there a reason the port being on could cause the starboard to go into rpm reduction?
Thanks

 

[rodbolt]

Re: 1999 sx150txrx alarm and surging

if its rigged correctly that engine can alarm for low engine tank level.
indicate will be either a red lamp,left bar or 3 bars flashing.
overheat will usually be found on the speedometer on that old of a model unless the tachs have been changed.
low battery voltage will do it as well and will be shown on the speedo.