The last engine I rebuilt was filthy and I used a WD40/degreaser and petrol mix which I left on for about an hour. I then scubed off with a scourer with some more degreaser and then rinsed off with water. Dried it and sprayed with gallons of WD and all the parts came up like new, literally... I'd be worried about blasting when 2 hours work got the result I was hoping for.
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NSR300R - Why did i ever have a 250...