I've been chasing this problem for a while. I see no leaks or residue, system holds 15# pressure for 30 minutes, I smell nothing unuusual from exhaust, see no white smoke from exhaust, no apparent leak from water pump. I lost 10oz in 400 miles a few days ago then lost 12oz in 200 miles yesterday. Coolant loss is inconsistent like that. Yesterday I opened the hood after driving 90 miles & saw the fluid level in the expansion tank was at the "min" level. I opened the cap, gas rushed out and the fluid level rose to "max". I've been watching this happen for several weeks now, is it exhaust gas? If it's exhaust gas, how do I determine source (head gasket vs cylinder wall vs cracked head)? If I have to pull the head, what is used to seal the upper & lower halves? On my 960 there was a pink sealant that I rolled on with a foam roller. Thanks.
Marlin