Mine is a continuous beep. Ruled out gear lube by unplugging one of the leads. Seeing the temp gauge higher than normal and seeing steam come out of the thru transom exhaust when idling and after turning off points me to the overheat issue.

the solid horn non stop ruled out the drive lube bottle and like I said the solid non stop warning horn are more severve fault(s).

Would bet on ECT overheat and EMCT overheat are the mix here and they are both solid non stop warning horns. The heat exchanger needs complete clean out -- all new anti freeze totally --- all gaskets and grommets need to be changed for the heat exchanger and related parts to it.

The Impeller and housing is another issue on top of as it is always the norm for those 2 items. They are not just on the 496 either so I see the gen VII water pump fail all the time. Boating season almost a daily item for an issue.

Always post what warning horn(s) are going off because it will eliminate some of the dart throwing by the ones whom really know what they mean plus what goes on with PCM 555 and ECM 555. - Was it ever posted what warning horn it was going off ?

Thanks BUP.
The primary culprit was the heat exchanger. It had accumulated a good bit of trash. Plus the temp gauge is reading 12 degrees higher than the actual temp. Gauge now shows normal operating temp of 176. Minus 12 means I'm running about 164. Before cleaning the heat exchanger and replacing the antifreeze normal running them was 190, so in actuality I was running 178.

[QUOTE=BUP;4635794]you can watch real temp with the scan tool. alot temp gauges at the dash are off with the readings.

Could nt have spelled it out any better.

[QUOTE=BUP;4636003] the solid horn non stop ruled out the drive lube bottle and like I said the solid non stop warning horn are more severve fault(s).<br /><br />Would bet on ECT overheat and EMCT overheat are the mix here and they are both solid non stop warning horns. The heat exchanger needs complete clean out -- all new anti freeze totally --- all gaskets and grommets need to be changed for the heat exchanger and related parts to it.<br /><br />Post 22 ^^^^^^^^<br /><br /><br />Could nt have spelled this out any better as well.