yes..there is a u tube video on it I think.Have not heard of that. I thought they skimmed them and there was a minimum spec.
I would clean it up thoroughly and just redo the head gaskets. You should be able to see by going under the car. there should be steaks on the passenger side Cat. where the coolant has been running down and drying on the hot cat..and underneath on the drivers side. the first thing that happens is the leak at the water passages on each end of the head. Then it usually steam cleans the affected cylinder. then the next cylinder over will fail(if it goes long enough) because the water doesnt compress and strains ands steams the head gasket at the thin part between the bad and the cylinder next door. it's a dirty mess though. Flush all that stop leak out of the entire system!! the next item to go will likely be the heater core, due to the overheat stress on it..take careMy 2000 Disco was purchased over heated and in operable. Compression test on #1 and #6 shows zero compression. The gauge bounced up to almost 30 but builds no compression. Tdc leak down test on #6 was complete failure it couldn’t hold any pressure. I found a bottle of head gasket repair in the back seat
I have a buddy who is convinced we can get away with just doing head gaskets.
what do you guys think?