Raising Bongo to Bleed Cooling System

[Long]

Hi,

i am wondering, i recently had over heating issues with my bongo http://igmaynard.co.uk/bongo/forum/view ... =3&t=72473,

i changed the thermostat, and bleed again, things look better now (no overheating, bottom hose warm after driving, hot after fast drive), and the level in the head tank is at full during test drive. however i drove uphill then the level in the header tank dropped to between low and full. i am thinking that this incline pushed some remaining small air bubbles into the head tank and thus lowed the level in there.

i am wondering if i should drive up a incline slope and leave it there running with cap off to force any last remaining bubbles out of the system? I know there are some horizontal hoses and air could be stuck there.

it hasn't overheated since the change/bleed, but i want to make sure all bubbles are out as sometimes when driving i think i hear bubbles in the system.

would leaving it in a uphill position be good for the cooling system and effectively push bubbles up to the top? once at the top i will add more coolant to bring the level to place if it drops.

thanks.

[Bob]

I can't think this would get air out of the head and stat.

[cmm303]

I would think driving it is more likely to tease the air out than running it stationary, though couldn't be recommended as a means of bleeding. Whilst having the nose up may help air travel along some horizontal runs towards the front, it will work against the flow on others and certainly wouldn't be enough to allow air to be pushed down the big drop in the top hose. Perhaps swings and roundabouts, depending on where the air was?

You were checking the level when the van was back on the level?

There is only one certain way to check for air accumulating in the head and that is to bleed. My own experience of this following a small leak was that a small amount of air had collected, presumably around the head or bleed tube, which came out almost immediately as a couple of bubbles, in the first couple of see-saws before starting the engine and then a bit more very quickly after starting the engine. Nothing more, although I did take the time to bring the engine right up to temperature.

[Long]

Hi was checking it again back at level.

i will try bleeding it again, but since i bleed it already, and it didn't boil over or over heat, there should be a lot less bubbles?