'78 Euro - Upon purchase there was water in the oil. I changed the oil and shunted the cooler lines off the radiator. Car had Hx of recent WP change, possible previous overheating for all I know, It amazed me - I put in a battery and fuel - this 928, which sat in a pole shed for a year, started and ran great for 3 or 4 minutes w/ no water in oil, pressures and temp WNL. Then the fuel hoses said "not now dear, I have a headache".... I Shut her down....

The $300 dollar learning tool. The PO thought it had a blown head gasket and this is why the car sat for the last year. I wonder.....
I have a radiator pressure gauge installed on the H2O tank right now. I pumped up to 15 lbs. - I don't want to blow the tank or lines so that will have to suffice. No drop in pressure at all - it's been over 1/2 hour.
I am unable to start the car to test further today due to fuel lines - same problem as the other '78 - as soon as I started it, it blew the soft fuel lines - I replaced them, then the rear ones blew too - just old and needing attention but I knew this when I bought the car
Question - shouldn't I loose water pressure on the gauge if the head gasket or radiator were bad? Thoughts?

 

You don't mention the transmssion type, but if an auto, check for coolant in the trans.

 

The engine needs a full heat cycle 15-20 minutes of running before you can determine that the gaskets are intact. It is possible that the heat exchanger was leaking oil into the coolant under 115 LBs of pressure but coolant at 14 PSI will not flow the other way.

 

I just/am going through this. You can block off the radiator connections and the oil line connections to the cooler from the sandwich. Get the engine running and if after the warm up time that Jim mentions, check the oil. I would probably keep checking the dip stick as the engine runs anyway as you will want to shut it down as soon as you see any cloudiness. If you find you have water in the oil again, head gasket is it.

As for the overheating, this is exactly what the symptom was for my car. In hind sight, all that was mentioned to me in my investigation was true. Look for bubbles in the expansion tank as the engine runs. If you keep getting bubbles, those are exhaust gases escaping into the cooling system.

You can just search my screen name and look at the last few threads I started. All of this stuff is covered in them.

Good luck!

 

Easiest solution is to have a chemical test of a sample of coolant to see if there are exhaust gases. Most garages have the kit, or buy one from ebay.
Ttakes 5 minutes, Quick, simple & cheap....

marton

 

Good point Jim, and well taken.
I'll pull it Friday after shift. I wanted to clean the engine compartment anyway
I knew this would happen

I was just trying for a break between engines - I just finished the 911 this week (only took me 1 1/2 years) and I think my wife wonders if I still live on the property
Oh well - guess I need to get more beer