Overheated and coolant spewed out of header tank

[samuel]

Have now bled the system twice and still getting a continuous stream of white foam from the bleed pipe.

With engine running, one fan cut in, then the next fan and the temperature stays steady at one third of the gauge. Obviously there is still an air lock, as the fans wouldn't normally cut in like this.

Will let it all cool down now and try again tomorrow.

[missfixit70]

Topic split as it had digressed, hijacking Tim's original post - split topic here - http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=31998
Now back on track.

Have now bled the system twice and still getting a continuous stream of white foam from the bleed pipe.

With engine running, one fan cut in, then the next fan and the temperature stays steady at one third of the gauge. Obviously there is still an air lock, as the fans wouldn't normally cut in like this.

Will let it all cool down now and try again tomorrow.

Don't go by the gauge if it's unmodified, as it won't move until it's got way too hot.
Did you do an exhaust gas test on the header tank?

[samuel]

Hi Kirsty

Have now decided to wait for my new hose to arrive (ordered last Saturday!). Will then drain the lot, flush through before re-filling and bleeding again.

Rooster is on hand and has very kindly offered to pop in and check for exhaust gases in the coolant.

Will be investing in a coolant alarm as soon as i've sorted this little lot out. Or 'BIG' lot out if thats the case.

Will keep you posted on progress and thank you for your support.

Tim

[mikeonb4c]

Hi Kirsty

Have now decided to wait for my new hose to arrive (ordered last Saturday!). Will then drain the lot, flush through before re-filling and bleeding again.

Rooster is on hand and has very kindly offered to pop in and check for exhaust gases in the coolant.

Will be investing in a coolant alarm as soon as i've sorted this little lot out. Or 'BIG' lot out if thats the case.

Will keep you posted on progress and thank you for your support.

Tim

Fingers, and various other bits, crossed for you Tim

[The Great Pretender]

[quote="haydn callow"]0.9 bar is best for the header tank....it really needs to be less than the one on the radiator....
quote]
Why? As they are both in the same pressure region of the system one relief valve would be needed at the highest point wouldn't it?

[haydn callow]

I expect this is total tosh...but....as I understand it ....if you had a lower pressure cap on the rad than the expansion tank...in the event of a "event" the rad cap would "blow" first....(would this be a good thing)?

So ..if you had the same pressure cap on both and the one on the rad was a bit "tired" there could be the same dangers.

What is the differance between a red and a yellow cap ? they both have 1.1 bar on them.

So my thoughts are...If it's going to "blow" I want the Ex tank cap to "blow" I can be pretty sure this will happen if I put a slightly lower rated cap on.

There is no reason "I think" for the rad to have a pressure cap at all....a simple blanking cap would do the job.

[scanner]

I expect this is total tosh...but....as I understand it ....if you had a lower pressure cap on the rad than the expansion tank...in the event of a "event" the rad cap would "blow" first....(would this be a good thing)?

So ..if you had the same pressure cap on both and the one on the rad was a bit "tired" there could be the same dangers.

What is the differance between a red and a yellow cap ? they both have 1.1 bar on them.

So my thoughts are...If it's going to "blow" I want the Ex tank cap to "blow" I can be pretty sure this will happen if I put a slightly lower rated cap on.

There is no reason "I think" for the rad to have a pressure cap at all....a simple blanking cap would do the job.

That is certainly the case on other systems I've seen - only ever one pressure cap.

I would want the higher of the 2 pressure caps to blow first as well. The tank cap is (or should be) above the highest level of the coolant, but, so far as I can see, the rad cap is well below minimum level, so if that blows first the pressure above it is going to blow a lot of coolant out of the system quite quickly.

Not, (I would humbly suggest), a good idea.

[patnben]

I seem to remember some time ago I had a look at the radiator cap and the outlet
was blocked off so it would do nothing if it lifted. Maybe it's only there so you can
have a look at the top of the radiator core or something equally obscure. I think
dandywarhol knows more about this than I do !!!.

[samuel]

The hose i have ordered still hasn't arrived. Ordered Saturday!

Not happy!!

Interesting note on the rad cap. I guess the cap is there whether its pressure relieving or not just to make it easier to bleed to the top of the rad level.

Never know may get a delivery by the end of the day. Ho Hum!!

[francophile1947]

Interesting note on the rad cap. I guess the cap is there whether its pressure relieving or not just to make it easier to bleed to the top of the rad level.

Probably so but, as scanner says, why have 2 pressure caps I have only ever seen one on the cars I've had - puzzling ain't it?

[mikeonb4c]

Is there any circumstance under which excess pressure could not find its way through to the branch line that the header tank is on in order to relieve itself? That might explain it I suppose. Certainly the Bongo cooling system (as pointed out many times!) is a convoluted thing

[kelv]

Is there any circumstance under which excess pressure could not find its way through to the branch line that the header tank is on in order to relieve itself? That might explain it I suppose. Certainly the Bongo cooling system (as pointed out many times!) is a convoluted thing

The man with the answer is saying nothing

Nothing kills germs faster than Domestos...................Domestos kills 99% of germs, dead............... Whatever.
I'll have a bottle of Nothing then, please

[dandywarhol]

A pressure cap on the radiator does NOTHING! There's nowhere for the pressure to go even if the valve opened.......................

[mikeonb4c]

A pressure cap on the radiator does NOTHING! There's nowhere for the pressure to go even if the valve opened.......................

Now I AM confused. Do you mean it does nothing because there is already a pressure cap on the header tank that should let go first?

[francophile1947]

A pressure cap on the radiator does NOTHING! There's nowhere for the pressure to go even if the valve opened.......................

Now I AM confused. Do you mean it does nothing because there is already a pressure cap on the header tank that should let go first?

No Mike - he means that, on the normal Bongo radiator, there isn't an overflow pipe, so the coolant can't go anywhere even if the pressure cap releases.