Danielsand
New Member
Wife's Hippo decided to start with its "fits" again.
Coolant expansion tank is BOILING. I replaced the tank, and the cap from the 'donor' car, and BOTH tanks have radial cracks (they look like surface cracks only) around the neck. I picked the one that looked better of the two, to no dice. Still boiling. There is no water in oil, and no oil in water. Heater works fine, a/c too. Temp gauge does not move from the middle (when cold shows "cold", and when tank is boiling, shows in the middle). No codes, no warnings.
Upper rad hose gets warm quickly, bottom one stays cool for a long time (on tickover), and gets hot (as it should) after the run. No leaks in the thermostat valley, no leaks on any hose connections, and no leaks on the water pump. Coolant circulates (indicates the pump is working). Fans work as they should (can't get them to come on on tickover, but they are on after the run, even after the shutdown for a brief period of time).
I just ordered a new tank and cap, and will try that. If no dice, I'll go for the thermostat replacement. If I'm changing the thermostat, I'll replace the manifold gaskets too. Since the oil is clean (and fresh), I'm discounting HGF.
Question, ......what's the pressure rating of the coolant cap? (I have two sitting on the bench, one is 110, and the other 120) The new one will be coming in with the new tank.
The only thing that changed on the car, was my tank replacement. The original tank had a different cap, and it was steaming a little from the relief valve on the cap, all the time after a longer run. This was annoying to me, so I replaced the tank, and that one has a different cap (not interchangable). Wife went for a longer run (100+F air), and the coolant was ****ing out from under the hood. Temp gauge didn't move!
What am I missing here?
Coolant expansion tank is BOILING. I replaced the tank, and the cap from the 'donor' car, and BOTH tanks have radial cracks (they look like surface cracks only) around the neck. I picked the one that looked better of the two, to no dice. Still boiling. There is no water in oil, and no oil in water. Heater works fine, a/c too. Temp gauge does not move from the middle (when cold shows "cold", and when tank is boiling, shows in the middle). No codes, no warnings.
Upper rad hose gets warm quickly, bottom one stays cool for a long time (on tickover), and gets hot (as it should) after the run. No leaks in the thermostat valley, no leaks on any hose connections, and no leaks on the water pump. Coolant circulates (indicates the pump is working). Fans work as they should (can't get them to come on on tickover, but they are on after the run, even after the shutdown for a brief period of time).
I just ordered a new tank and cap, and will try that. If no dice, I'll go for the thermostat replacement. If I'm changing the thermostat, I'll replace the manifold gaskets too. Since the oil is clean (and fresh), I'm discounting HGF.
Question, ......what's the pressure rating of the coolant cap? (I have two sitting on the bench, one is 110, and the other 120) The new one will be coming in with the new tank.
The only thing that changed on the car, was my tank replacement. The original tank had a different cap, and it was steaming a little from the relief valve on the cap, all the time after a longer run. This was annoying to me, so I replaced the tank, and that one has a different cap (not interchangable). Wife went for a longer run (100+F air), and the coolant was ****ing out from under the hood. Temp gauge didn't move!
What am I missing here?
Last edited: