Radiator problems and questions

[Diplomat]

Surely the cap on the rad must be rated for a higher pressure than the one on the expansion tank?

You don't want the rad cap blowing off at all.


Frank

[missfixit70]

It doesn't, there's no vent on it, it relies on the fixed top seal, go look if you don't believe me Any venting on the coolant system takes place at the header.

[haydn callow]

There is no pressure release outlet on the radiator so the marked pressure on the cap is irrelevent......

there are 2 seals on a pressure cap...the lower one that is spring loaded to whatever pressure it is rated at.....this allows high pressure to be released via the stub outlet on the neck of the rad.....as a bongo doesn't have this stud it dosn't matter if this lower seal is there or not.....the top seal which is on the underside of the cap is a "solid fixed" seal and will hold any amount of pressure in......the ex tank is where the pressure is released on a Bongo...


Think that makes sense.

[haydn callow]

Kirsty.....done it again....but I think my reply is more comprensive

[missfixit70]

I'd say mine was more concise At least it says the same thing

[Bob]

Great double act guys.

[Diplomat]

Yeah, that all makes sense to me.

My initial thought was that you wouldn't want a 0.9 on the rad and a 1.1 on the tank.

What I didn't know was that the cap couldn't ultimately leak around the top seal, no matter what. After all, if it is normally blowing off into a tank via the spigot outlet why would they bother proofing the rest of the cap too seriously? I assumed that the Bongo rad cap was not the normal blowing type but a dumb version.

I won't go and look at my rad cap, Kirsty, as that would go against my rule of not removing it in case I cause an air lock!!!

I've put a Dymo label nearby saying 'Do not remove cap' and would suggest that this would be a good idea for others to follow especially if taking them to any old garage for a 'service'.


Frank

[missfixit70]

What I didn't know was that the cap couldn't ultimately leak around the top seal, no matter what. After all, if it is normally blowing off into a tank via the spigot outlet why would they bother proofing the rest of the cap too seriously? I assumed that the Bongo rad cap was not the normal blowing type but a dumb version.

Not sure what you mean by this? No tank for the spigot outlet on the header tank to vent to - just atmosphere, no spigot outlet on the rad at all.

[Diplomat]

What I didn't know was that the cap couldn't ultimately leak around the top seal, no matter what. After all, if it is normally blowing off into a tank via the spigot outlet why would they bother proofing the rest of the cap too seriously? I assumed that the Bongo rad cap was not the normal blowing type but a dumb version.

Not sure what you mean by this? No tank for the spigot outlet on the header tank to vent to - just atmosphere, no spigot outlet on the rad at all.

Sorry, Kirsty, Instead of 'normally' I should have said ' in vehicles other than Bongos'. I should have realised that 'normal',for us, means Bongos !!!


Frank

[missfixit70]

More like, when it comes to bongos (& their owners), there's no such thing as normal

[alant54]

Where would we be without our resident phsycologists.... ....the BFS ( Bongo Fury Site ) does benefit where the NHS is missiing out....

Alan

Ps is there a h where it shouldn't be...

[johnzbenson]

I have recently bought and fitted a new radiator from Budget radiators off EBAy- the radiator has a two year warranty and after having to send the radiator back becuase of damage in transit- I can recommend them as providing no quibble returns etc- I did think my head gasket had gone but with the excellent bleeding procedure on here from Haydn Callow ( large funnel attached to the flexi hose under the passenger seat check it out on Utube and yes it will take some and will only prove effective if the bottom hose is allowed time to get hot)
I understand the concerns regarding the thermosat slow acting issue and yes it will reveal the weakest part of the system- for what its worth change it before refilling system.