82 ski tique overheating, Raw water pump good tho?

Got a problem with the 82 ski tique I recently purchased. I found when testing it for the first time the other day it had no thermostat and would barely register on the temp gauge.

Ordered one and fitted today and now it overheats so someone must have removed it to solve a problem.

On removing the themostat housing when it had overheated I could see the thermostat was open and indeed on testing the stat in hot water it opens and closes fine.

Now I've pulled the raw water pump hose and there is a very good supply of water from this. The manifolds stay lovely and cool when the engine is overheating so I don't think this is a water supply issue.

I pulled the engine waterpump thinking maybe this was the issue but I can't see any problems with it. Bearings seem good and impellor has corrosion but not loads. Any way I can tell if this is a marine pump or not? I'm thinking maybe an automotive one and because it's a reverse rotation engine it's not pumping enough water?

Anyone else got a suggestion?

The water pump looks original. Its paint finish and overal condition match the rest of the engine which is untouched.

The blades are straight radial.

Stat is, oh wait my bad....... a 180 stat!

Yep that'll be why it's running up around 180-200 degrees.

What a wally I am!

Where's Roger then? I'm in Essex which is over on the east coast.

You know I spent a couple of hours pulling the whole cooling system last night for nothing!

Yeah we all live close to London and often have tea with the queen

Anyhow new stat fitted this eve and all good. Now if i had ordered the right one in the first place I would have saved myself 3 hours work!

Still I cleaned out the stat housing, water pump and raw water pump and gave them all a like of paint. Now to paint the rest of the engine to match.