coolant flow - (follow up to cooling diagram)

[widdowson2008]

looking good steve

But it still needs a dose of 'Fixit'

[Fredalier]

Does't that filling animation, assume a cold engine (thermostat below 80 degrees) and an engine that is not running?

[mikexgough]

nice animation, but the air pocket that is left in the animation at the thermostat will only occur if the bung is removed on cold system fill and also if the system is allowed to expel air bubbles.....(taking out the bleed hose bung)... if you don't then chances are more air can be trapped in the system...

[widdowson2008]

Does't that filling animation, assume a cold engine (thermostat below 80 degrees) and an engine that is not running?

That's right - filling an empty system from scratch assuming system has first been completely drained (as the animation) such as when a new stat has been fitted.

mike - If you take a look, you'll see a funnel in the bleed tube - the bung is already out.

I also qualified things by saying it was 'tongue in cheek' and nowhere near finished yet.

[mikexgough]

mike - If you take a look, you'll see a funnel in the bleed tube - the bung is already out.

I also qualified things by saying it was 'tongue in cheek' and nowhere near finished yet.

Ahhhh so it's a funnel.......... didn't realise....... probably coz i don't use one...... other than to fill the tank.....

[widdowson2008]

mike - If you take a look, you'll see a funnel in the bleed tube - the bung is already out.

I also qualified things by saying it was 'tongue in cheek' and nowhere near finished yet.

Ahhhh so it's a funnel.......... didn't realise....... probably coz i don't use one...... other than to fill the tank.....

Yep - just as shown in Chells video

[haydn callow]

excellent diagram...only comment....the ex tank needs to be a little higher......you show the tank as part filling via the rad filler......this is not what happens......

[widdowson2008]

excellent diagram...only comment....the ex tank needs to be a little higher......you show the tank as part filling via the rad filler......this is not what happens......

Hi Haydn - thanks for your comments.

Just been out to check and in fact the Xtank is shown a little too high, but not much.

The dimensions on my Bongo are:

Floor to extreme top of radiator = 970mm
Floor to bottom of expansion tank = 930/935 (not easy to get a direct reading due to curvature on bottom edge of X/tank )

This means that when the radiator is full to the top (to the point of overflowing), there will be a depth of 35/40mm of coolant in the expansion tank.

Not arguing on this one Haydn - just looking at the numbers.

[haydn callow]

Hmmmm!!!! see what you are saying...BUT....(always a but...) I am pretty sure that in real life the tank is empty when the rad overflows......most tanks are to dirty to observe this....I will be fitting a nice clean tank soon so I will make a point of seeing what happens...

The pipe that runs from the top of rad to tank runs parallel to the top of the rad in it's clips. (slightly lower than the top of rad so I would expect this bit to fill via the rad) then it slopes gently upwards and enters the tank a little way up from the bottom....I reckon this is a tad higher than the top of rad..

As I said I will observe and report when I fit a clean tank.

[widdowson2008]

Look forward to your findings Haydn.

[Fredalier]

I cleaned the inside of my expansion tank enough for coolant to be visible again, by using a swill of beach sand in soapy water and shaking the devil out of it for about half an hour. Then I spent another half an hour making sure every grain of that sand was gone out of it again before putting it back. With hind sight, buying a nice "shite and briny" new one was probably a better option, but there's a cheaper option for you in case anyone is interested.

[Northern Bongolow]

i did similar with mine using some fine pebble dash off the side of the house,worked a treat.
as said above though make sure you get it all out after.

[Fredalier]

BTW, again on the coolant filling fun animation.

You show inside the head at the top a step between the bleed hose port inlet side and the top hose outlet side, with a small gap that doesn't get filled right at the top of the head on the inlet (bleed) side only.

That gap is in fact the whole width of the head, not just the passenger side. The water stream through the head (top is flat, but floor undulates a little) is 47-49 mms deep, in case that helps with proportions of your diagram.

Not wanting to nitpick, but that bleed gap at the top of the head, is really important. So serious is it that it is the reason our engines are positioned on a slight slope to minimise it.

[mister munkey]

Not wanting to nitpick.

I think thats the point, nitpicking is being positively encouraged to get this right.

[Fredalier]

Is someone nitpicking about my nitpicking?

Also, relative heights of coolant inlet to head and outlet from head are not quite right. The centre of outlet is 80mm below rocker cover gasket: centre of inlet is 84mm below rcg. The ceiling of the water chamber inside the head is 57mm below rocker cover gasket.