98 Merc 200 alarm at high rpm

[aquasport1998]

Hello again guys. More questions. Replaced impeller that was shredded. Put her back in the water and have a stream out of the tell tale. Ran her for about 5 minutes at 4000 rpm and got an alarm. Shut motor off. Sat for a few minutes. Started up again, good stream and idled back toward dock. No alarm. Ran her up to plane again and got an alarm at high rpm. There is a strong stream at high RPM.

So, what to check now.
Noticed that there is no water coming out of exhaust hole near tell tale (not sure if it supposed to or not, but a buddy who has a Yamaha says he gets water out of the exhaust).

No alarm at low speed or idle.
Could it be a bad thermostat? Poppet valve?
I am wondering if there is debris from the shredded impeller in the water lines or in the head. If so, how do I clear them or is that something that requires a shop visit?

Is the alarm even related to the water pump issue? Could it be an oil injector alarm? What does THAT sound like?!

Anything else I should be thinking about?
Thanks, guys.

 

[Barnacle_Bill]

Re: 98 Merc 200 alarm at high rpm

That is a symptom of a bad poppet valve.

 

[Dreworr123]

Re: 98 Merc 200 alarm at high rpm

shift interupt switch? if its only above 4000 rpm the engine might sound thinking youre over reving in neutral

 

[aquasport1998]

Re: 98 Merc 200 alarm at high rpm

thanks, bhile. how do I test for a bad poppet valve?

Thanks, too, Dre. How do I test for a bad shift interrupt switch

aqua