Is it producing bubbles at the radiator neck when cap is removed?
Brings up the concern about proper liner projection.
What's the status of the radiator core?
maybe your water pump is sucking air in the shaft seal and it builds up and pushes the water out. if it were a liner or precom, engine speed should not affect the air ingression. the faster the engine runs, the more negative pressure at the centre of the water pump impeller, may be enough to draw in air if the seal is dodgy.
just a thought from out side the conventional box.
[quote="rmyram"]maybe your water pump is sucking air in the shaft seal and it builds up and pushes the water out. if it were a liner or precom, engine speed should not affect the air ingression. the faster the engine runs, the more negative pressure at the centre of the water pump impeller, may be enough to draw in air if the seal is dodgy.
just a thought from out side the conventional box.[/quote]
I will check it out, but we just had it rebuilt. Thanks for the help.
Whether you had compression leak or air drawn into the cooling system it would still vent at the filler neck. Have you checked thermostat function?
Do you know what the actual liner projection readings are?
Did the condition change after rebuilding the water pump?
I'm not absolutely sure but I think it should have a 13lb pressure cap, if its not pushing air out of the radiator, I would be looking for a restriction in the radiator or transmission cooler, just a thought, take a look at what is happening to the bottom radiator hose when you open the throttle right out.
I'm not absolutely sure but I think it should have a 13lb pressure cap, if its not pushing air out of the radiator, I would be looking for a restriction in the radiator or transmission cooler, just a thought, take a look at what is happening to the bottom radiator hose when you open the throttle right out.
Whether you had compression leak or air drawn into the cooling system it would still vent at the filler neck. Have you checked thermostat function?
Do you know what the actual liner projection readings are?
Did the condition change after rebuilding the water pump?