Club 80-90 Forums

I have an urge to do the Libby Bong thing. A couple of questions for those who have done this in the UK.

1) How far below the bottom of the bong should the siphoning pipe go? IE how far down into the header tank?

2) Where the siphon pipe goes through the main bong pipe did you find an easily available fitting or just make it an 'interference fit' with a bit of sealant? Don't want to lose to much precious G13.

3) Anything else UK centric?

I reckon the rest is covered in the long thread on the Samba site


Will soon be heading to the builder's merchants...

It's my understanding that the siphon pipe (optional, only function is to catch the coolant thatll be in the full main bong pipe), would just inteferance fit into the bong pipe, just above the lip of the header tank and protrude inside by a cm or so. Ie, it doesn't go into the header tank at all. Don't see why it would need to?

You're bound to lose 'some' on the ground with any coolant job

I take your point, it (siphon pipe) just needs to be in the neck of the header tank, ie to the level you'd want coolant to be in the tank.

Forgot to add, another benefit of the siphon pipe, if it is transparent, is to show you the coolant level in the bong.

For anyone who doesn't know what a Libby Bong is check out this samba thread.

I thought it was for Weedheads

Cobra88 wrote:I thought it was for Weedheads

It is! If you're not stone you can manage to bleed it the normal way

That seems to be a rather over engineered version of my inverted Tesco two litre plastic milk bottle with a B & Q 8mm plastic pipe in the cap which is hung from the hinge of the rear door and plugged onto the small pipe on the Dalek valve. The bottle has the bottom cut off and holes are made for string to tie up high to the hinge The bottle hangs like a funnel with gravity doing the work and in my case the van is sitting on a gentle nose up slope. I guess the Libby Bong could be mildly pressurized to speed things up but I find the gravity process gives me time fussing around bleeding, squeezing hoses and topping up the bottle etc. A brake pipe clamp can be used as a tap in the pipe to recover unused mixture. The whole process works for me without bringing the system up to operating temperature which might be problematic with my admittedly flimsy set up. A run round the block flushing out any sly little air pockets will result in a top up as necessary.

Unless of course have completely misunderstood the Bong...

What a faff!
Just lift the front and in the engine at 2000rpm whilst tipping coolant in until no more will fit !

Mocki wrote:What a faff!
Just lift the front and in the engine at 2000rpm whilst tipping coolant in until no more will fit !

Heh yes, we've all tried that too... But it's not without its hiccups and spills whilst making a helluva racket and going to the rad bleeder over and over. I'd be up for trying the bong aswell

Our American counterparts do like a bit of over engineering.

A bit of white sink waste pipe from B&Q with a few wraps of quality gaffer tape works equally well. All the other bits don’t really add to the overall experience!

All you want to do is raise the water level in the header tank to higher than the radiator bleed valve.

I take on board it’s not to everyone’s taste, but I’ve found it’s the easiest way to bleed the van quickly and reliably.

Cor I like the idea of Mr Bean's to re-use an old Dalek cap, presumably with valve removed. Seems like a very simple approach!

Michael4 wrote:Cor I like the idea of Mr Bean's to re-use an old Dalek cap, presumably with valve removed. Seems like a very simple approach!

Oops I used the existing perfectly functional Dalec cap. You have got me thinking now
But if I have it right:

If you start off with a full "pressure" tank any increase in volume - expansion due to the temperature coefficient of the coolant is expelled into the overflow tank. Then the expelled coolant will be drawn back into the "pressure" tank from the overflow tank when the cooling system comes back down to ambient thus restoring the situation.

For this to happen Dalek cap should open in one direction when the specified pressure is exceeded and open in the other direction (the return path) such that normal atmospheric pressure in the overflow tank (remember hole in cap) can drive the displaced coolant back into the "pressure" tank when the system returns to ambient temperature the now cooled coolant having reduced down to it'e original( lower) volume.

Thus seeming blocked when you blow into it and making a farting noise when you suck on it. Of course if you could blow at above the specified cap pressure it might pass wind in the other direction as well. (borderline family reading )

So my use of the existing good Dalek cap and less than a metre of head sounds more feasible now - leastwise to me.

errrmmm...yes but no but yes but...I'm new to this but...etc...

If you leave the Dalek cap intact and operating then it will continue to work as it should. Your new reservoir of coolant will act as a relocated top up tank. The coolant will need to be sucked or pushed through the Dalek as per normal, that it is higher than the header and radiator bleeder may or may not make any difference.

Also with an operating Dalek when you undo the bleeder you will loose pressure or vacuum and therefore fluid will not get pushed or sucked through the Dalek.

If you remove the internals from the Dalek then it simply acts as an easy connection to your supply of coolant that is higher than the radiator bleeder. Gravity will do the rest. In effect a simplified Libby Bongo.

If the above demonstrates that I really do not know what I am talking about please tell me!

I would also suggest that Aldi or Lidl milk bottles for the reservoir might be more appropriate. Those with very smart T25s may prefer Waitrose...