[jjesam]

Hello and Help me.
There is oil and exhaust gas in the expansion tank which boils over. I've checked
the purge line, nipple; clear. The engine runs smoothly. Heater works.

 

[Submariner409]

Welcome (sadly) to the Funny Farm !!!:highfive:

I'll move this to Engines, Northstar - you'll get more varied input there.

Please read the several stickys on the main Northstar forums page. Cooling fans, cooling system, gauge operation. head gasket and repairs.

You have the classic symptoms of a bad gasket caused by failure of the cylinder block head bolt hole threads in one or more bolt holes.

 

[Ranger]

How have you verified exhaust gases in the cooling system? That is the kiss of death.