1990 Ski Nautique - Overheating / 'Flushing'

Hey all - first post.   Thanks for the site, wealth of knowledge already.

Did a few reads, but couldn't find something that I was looking for...may not exist, but felt I should ask.

A friend keeps her 1990 Nautique at my house - it wasn't used from November through last weekend, battery was dead so we had to recharge in the boat lift. Did a 'dry start' to kick it over and probably (definitely) left it run a little too long forgetting it needed to draw raw water to cool.

Melted the impeller. Once we got the engine running without the jump, we tried to get it out on to the lake but immediately started overheating. TOTALLY melted the impeller.....nothing resembling the rubber flaps even remotely still present.

I pulled them impeller assembly without issue, and disassembled (marine shop is locating the correct rebuild for me) but I was then warned about making sure I pulled everything else apart and flushing the engine to ensure that none of the pieces are still clogging the water cooling lines, etc.

Question - what needs to be checked? I am mechanically inclined but I don't necessarily know the names of what I am looking at....so I can easily trace hoses, remove and reinstall, etc. Wasn't sure if there was a way to back flush with water to push any debris out the way it came in - or is it only a few of the hose assemblies in the front of the motor. Is there a MAIN concern point that I should be....well, concerned with?

Thanks in advance.

Welcome Paul. You don't have too big a job to do. Go and get yourself a thermostat gasket for say a 1990 5.0 Mustang and pull the thermostat cover with the arrow below. The "extra" parts can accumulate there or in the hoses going from that cover to the exhausts so you can remove the hoses from the exhaust manifolds and check inside them and in the brass 90's on the manifolds. If you don't find anything don't worry. Put it back together and fire it up.

When you remount that raw water pump it can go on either way If the engine runs in the normal automotive direction,left, the screw you see on this pump goes toward the block.

Gary - thanks man. LOL.

After I got it off I had that thought run through my head that went something along the lines of "this isn't universal....it has to be position oriented...."

So to understand you - if I were on the starboard side of the boat, the pump is located inline on the front right side (starboard) side of the engine. The pump as pictured above in your reply would need to be FLIPPED - pulley still to the front, but the side screw that I see would actually need to facing IN towards the block - correct???

I believe that to be the orientation it was when I took it off.

And THANK you to everyone else -

Wrong.

A screw faces the way it goes inro a hole. A person faces the way they walk forward. A boat faces the bow. A screw faces the pointy end.

Hollywood wrote: Wrong. A screw faces the way it goes inro a hole. A person faces the way they walk forward. A boat faces the bow. A screw faces the pointy end.

And a man has no name......