My diesel engine at 94000 km with good service record has exacly the same issue, no indication engine was overheating, gauge normal, no white smoke or anything but coolant would rise on the reservoir tank..combustion test determined there is combustion gas present in the cooling system..had to take it back to the dealership to be sorted
I had a block test performed and it went from blue to yellow but I have no white nor black smoke coming out of the tailpipe and I do not have the bubbles in the reservoir either. Is it still a gasket that is bad on the engine?
Holden went to a neoprene rear main oil seal in the HQ Kingswood in all of Holden 6 cylinder & V8 engines & they went back to the rope rear main oil seals later on in the series 2 HQ Holdens I think just like the 179 cubic inch Holden six in the EH Holden had in it in 1964. A cut down 3.8 litre Buick LN3 (VN Commodore) rubber rear main oil seal can be fitted into the rope seal engines once the knurling has been removed from the rear main seal journal on the crankshaft. I had trouble sealing up an early 3.8 litre Buick LN3 V6 out of a VN Commodore with a rope rear main oil seal, apparently they didn't have a knurled rear main oil seal journal like the Holden engines did, they were getting repaired under warranty by Holden for leaking rear main oil seals & Welch plugs from what an ex Holden dealer mechanic told me. I can remember when my father was telling me that he had no luck doing a neoprene rear main oil seal replacement in his old 6 cylinder HQ Holden Kingswood wagon,his was a series 1 HQ Kingswood !
