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2001 soft top jimny
Had my jimny for ten years and fluid levels always been spot on,however with this recent seriously cold weather thought maybe time to refresh the antifreeze.
Drained the system and refilled with plain water twice to flush out the crap until all was running clean. emptyed again and refilled with proper mixture in accordance with workshop manual directions.
Test drive a couple miles to circulate,heater fine, temp gauge fine, no leaks and allowed to cool, Checked to see if ok, however water level rose in overflow tank and radiator was down by same amount assumed trapped air working round system so empted overflow to correct level and topped up rad. left a few days checked levels fine and went for another short trip and same happened again.
Am I doing something stupid here, do jimnys have any hidden airlocks. Aways do with heater open
Have done many cars over the years without hassle and a couple of renaults in the past have have had bleed valves in the heater hoses.
Would like to sort before Xmas driveround at Bordon
It's normal for the level in the expansion tank to rise by 1/2 - 3/4 of an inch when the coolant gets hot from normal use. There is a spring in the rad cap to allow it and it siphons back as it cools.
Kirkynut
The underdog often starts the fight, and occasionally the upper dog deserves to win - Edgar Watson Howe.
Thanks Kirkynut,yeah I understand what you saybut the fluid level is rising by about 11/2 inches and not flowing back on cooling.
Will top up rad again and syphon expansion tank to proper level and see what happens.
System was fine before levels never moved, only items disturbed were drain tap and radcap (which does not appear damaged)
Perhaps radcap not seating properly allowing expansion but sucking in air on cooling instead of dawing fluid back
Were you able to narrow this down and fix it? I have the same problem after a flush. Have bled out any air, smelt the coolant- it smells free of exhaust gas and the rad cap looks intact.
Can't see what else could be causing this problem.
