Just used "Irontite" in an M50, so I could drive it to the junkyard.
This product was recomended by my neighbor, who owns a Napa store.
I purchased the product at CarQuest, $12.00, and the guy behind the counter said his commercial accounts swear by it.
Of course, he said none of them would admit it.
Mechanics, you know.
When I blew the head, it would harly run.
White smoke, chocolate milk in the valve cover, the whole cha-cha.
I followed the instructions, and the damn thing ran great.
However, I still took it to the JY, as I broke even on the deal, and too much other stuff needed to be fixed.
Oh, it won't clog anything that isn't designed to be clogged.
Remember, this is the cooling system, not oil journals.
Besides, it's F'd up anyway.
Fun & games,