451 overheating, even when moving

Bewy said

You crap in the rad comes from the engine. You can flush it until the end of time & still not get rid of all the debris. The way to fix the problem is to fit a filter to the top hose which catches the debris before it blocks the rad tubes. See below.

View attachment 1716119560

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A lot of the bits are orange, pretty sure that's RTV in there as well, and yes a filter is a good idea, got one coming today. Thanks!

There's even orange RTV being used to seal the exhaust at the collector, maybe it was red at one time and faded over the years.