Truck: Mitsubishi Shogun Sport 2006
Got a problem which started yesterday. Arrived at my farm gate and I could hear a "bubbling" from the engine compartment, so had a look. The overflow from the expansion tank was overflowing and both the tank and radiator were making "bubbling" noises. Dash temp was normal.
Added coolant in the expansion tank this morning and did a test run. Truck was fine for about 35kms until I got to a long hill, started going up and after a few hundred metres, I could hear the "bubbling" noise. Kept going for about 6kms (it's a long slope with steep and nearly flat sections) before stopping.
Been running the engine whilst stationary for a bit now and no "bubbling". Electric fan works, dash temp normal, oil clean. If I squeeze the top rad hose with the rad cap locked, I can push fluid into the expansion tank and with the rad cap unscrewed, no fluid movement, so the rad cap seems ok. Tried with heater blasting or aircon full on, with no problems.
So all I know is everything works fine until the engine is under load to climb a hill. Truck goes fine otherwise (no smoke of any colour), so I'm baffled. Any ideas anyone?
This truck has a hard life as a farm truck and I try to keep a preventative maintenance plan going for it. It passed its annual inspection a few days ago.
TIA
Got a problem which started yesterday. Arrived at my farm gate and I could hear a "bubbling" from the engine compartment, so had a look. The overflow from the expansion tank was overflowing and both the tank and radiator were making "bubbling" noises. Dash temp was normal.
Added coolant in the expansion tank this morning and did a test run. Truck was fine for about 35kms until I got to a long hill, started going up and after a few hundred metres, I could hear the "bubbling" noise. Kept going for about 6kms (it's a long slope with steep and nearly flat sections) before stopping.
Been running the engine whilst stationary for a bit now and no "bubbling". Electric fan works, dash temp normal, oil clean. If I squeeze the top rad hose with the rad cap locked, I can push fluid into the expansion tank and with the rad cap unscrewed, no fluid movement, so the rad cap seems ok. Tried with heater blasting or aircon full on, with no problems.
So all I know is everything works fine until the engine is under load to climb a hill. Truck goes fine otherwise (no smoke of any colour), so I'm baffled. Any ideas anyone?
This truck has a hard life as a farm truck and I try to keep a preventative maintenance plan going for it. It passed its annual inspection a few days ago.
TIA