273 overheating after new timing chain set and waterpump

pishta said

This is supposed to be an A/C NOS water pump. PN 3004763 I think the later '30' number denotes a later design year.
1965 parts manual shows a 10 blade plastic impeller but also shows 2 part numbers, A/C and non A/C for the 273
View attachment 1715557787

1964 Thru 1967 273 CI

1967-9 318 CI with A/C

1969 340 CI with A/C

Click to expand...

So there is a 6 blade! Well mine did have a ten blade, as I said, I counted them today (glad it didn't have 11, I would have run out of fingers and thumbs ha ha). So I wonder why they put a 10 blade on a tiny 273? I'm thinking I should try to have my old one rebuilt if I can't find another 10 blade at a reasonable price. Now I know what some people mean when they say these old beasts can be money pits. Wow.
Thanks Pishta