Bongo Fury

Thought the coolant system was low as indicated on reservoir.Topped up,engine ran,On stopping expansion tank spitting and farting.Released pressure and excess fluid.Level returned to low mark.Bongo seems happy enough but with all the scare stories i thought i would ask for any ideas or if the low level is usual? No apparent leaks,top hose warm not hot . Cheers Telboy.

Sounds like you have an airlock. Tons of info on the forum on how to bleed it, plus a YouTube video (search for Mazda Bongo Bleed).

How low was it before you filled it the first time ?
Its not actually a reservoir but a degassing tank, and if the level falls to low you can get air into the system, if so it needs to be bled.

It was sitting on the Low Mark.

Is there any history of problems ? Anything been done to the vehicle / engine / coolant of late ? Have you had to top it up at all before ?
Assuming this is a diesel as well ?