I agree, running cold is not a long term solution. I just thought it might hide some symptoms when it is this way.
I guess I will try different brand of thermostat tomorrow and failing that do some head gasket testing.
I'm not sure what mrfuelish is referring to about rubber wearing down. The pulley that drives the pump is just a metal pulley on this model. Maybe on the 1.6 things are different.
Thanks again for all the guidance and help! Will report back tomorrow.
He's referring to the crankshaft pulley - not the pump pulley.
The J series (and H series) Suzuki engines have one significant difference from the perhaps more conventional cooling systems (like the G series) - the thermostat is located 'downstream' from the radiator, in the cool return side of the loop AND THE COOLANT FLOWS THROUGH THE THERMOSTAT IN THE REVERSE DIRECTION.
It is important to recognize this for two reasons ...
- the first reason is that the thermostat is not sitting in the water outlet elbow surrounded by hot coolant - it requires coolant to be circulating through the heater core and returning to the back of the thermostat to warm the wax pellet - if this flow is blocked the thermostat will not open - you can bypass the heater core with a loop of hose to check to see if a blocked heater core is the problem.
- the second reason is that the wax pellet in the thermostat has to push the valve off of the seat IN THE OPPOSITE DIRECTION TO THE FLOW OF COOLANT.
Once you have verified that a blocked heater core is not the cause of your problem, I suggest you try an SGP thermostat (it should be available from SouthWest Suzuki motors)