Looked into why the mate's big Ford would spike in temp in traffic.
Near new radiator.
Big thermo fans.
Timing is good.
Coolant is good.
The only problem is, the design of the radiator doesn't allow you to see inside it.... at all.
So, the radiator came out today to have the tanks knocked off and checked/cleaned.
I warned Doug, next item would be the water pump.
When I spun the pump by hand, it had a bit of bearing rumble, so off she came.
Now, as I was watching Doug lift it up and out..... I said, the friggin impeller is miles from the body.
Got it on the bench, checking it out, and the clearance was fine.
Turned the impeller, and the bastard was all over the shop like a mad woman's breakfast.
The impeller has a very healthy crack in it and would turn like a very buckled wheel.
OK, order a new pump, dropped the radiator to be opened and cleaned to be sure...... she's gunna run cool soon.