VW type globular expansion bottles.

[ajlelectronics]

I am about to see another Chinese alloy expansion bottle fail, so it is time that I sorted it properly. I have grafted in one of the VAG coolant expansion vessels previously on a Scimitar but I can't recall what the (aluminium) bracketry that I made looked like, although it was mounted with both 'ears' to the inner wing.
For my GTC, I need the spigots at right angles to the inner wing and so I have to design a different set of brackets. That's not too difficult for the midpoint mount, but I feel sure that it needs a cradle of some sort underneath, to stop it bouncing around.
Can anyone illustrate how they are mounted in their own vehicles please?

For VW Golf Mk4 1997-2004 Radiator Coolant Expansion Header Tank & Cap | eBay UK

Suspension Tie Rod Ends. Mirror Glass. Car Body Components. Extra Information (If Applicable): Tank complete with Cap. Model: Golf. Complete Mirrors. Front Fog Lights. Complete Wheel Bearing Kits.

www.ebay.co.uk

 

[badabec]

Could @Hood make you one?

 

[ajlelectronics]

Could @Hood make you one?

I think that I have asked before, not that good man particularly though. I do have two split ones that could be used as a pattern though. My other reservation about sticking with the alloy is that there is no level indication, although that is not so much of an issue, I just dip it.

 

[james butler]

could you use the older level type vw sensor? i have one in my scirocco expansion tank i think it uses the coolant as a conductor or something but when it drops low enough breaks the circuit bringing level light on

Coolant Level Sensor Including O-ring Seal, 2 pin

Coolant level sensor including O-ring seal, 2 pin. For connecting plug with NO locating grooves.

www.heritagepartscentre.com

i have a feeling a normal rad temp boss will fit this so you can have it welded to the top of your alloy tank and screw the sensor in?
just a thought if your having a tank made

 

[ajlelectronics]

could you use the older level type vw sensor? i have one in my scirocco expansion tank i think it uses the coolant as a conductor or something but when it drops low enough breaks the circuit bringing level light on

Coolant Level Sensor Including O-ring Seal, 2 pin

Coolant level sensor including O-ring seal, 2 pin. For connecting plug with NO locating grooves.

www.heritagepartscentre.com

i have a feeling a normal rad temp boss will fit this so you can have it welded to the top of your alloy tank and screw the sensor in?
just a thought if your having a tank made

That is certainly a thought, thank you. It would need to be halfway down or so, to give expansion room.

 

[badabec]

Could the Chinese one be repaired by a tig-er on here? Doubleboost perhaps?

 

[jmp49]

If you do, and you may already have this but its not readilly visible, but it might be a good idea to provide some kind of isolation mount for the alloy tank to avoid vibration leading to fatigue cracks longer term.

 

[ajlelectronics]

If you do, and you may already have this but its not readilly visible, but it might be a good idea to provide some kind of isolation mount for the alloy tank to avoid vibration leading to fatigue cracks longer term.

The design is not good and could be improved. It is mounted on one side only, with an L shaped bracket. There is a hard foam pad underneath to stabilise it.

The failure is not through vibration; what happened in manufacture is that the seams were welded up, then linished for appearance. That removed most of the weld. When the bottle is under pressure, the seams start to weaken and split. You can't see it when cold, you have to watch for steam when it is hot. It had me head scratching for some time!

 

[jmp49]

Also, this clear things up for you?...

The quick summary is it has a nub at the bottom to locate in a hole in the body, and two bolts on the flange to keep it down. Then the hoses probably add some stability.
A lot of modern stuff is done in a similar way, they always feel a bit wobbly but I guess thats to avoid vibration shortening their life.

 

[addjunkie]

We have a member who makes many such things from ali, in NI if I remember correctly…. @Cheesie perhaps

 

[steveo3002]

 

[ajlelectronics]

Also, this clear things up for you?...

The quick summary is it has a nub at the bottom to locate in a hole in the body, and two bolts on the flange to keep it down. Then the hoses probably add some stability.
A lot of modern stuff is done in a similar way, they always feel a bit wobbly but I guess thats to avoid vibration shortening their life.

Extremely helpful, thank you.

 

[ajlelectronics]

 

[jmp49]

SEMA tig welds, look great on first glance, but when examined closely lead to lots of head shaking...
Can be fitted to cars with bluetooth driveshafts and other such show features

 

[bricol]

I have to say, and I might have done in the past on another thread, that I don't like that straight hose direct to the expansion tank, clipped to the engine. All engine vibration, movement, gets put into that fitting on the tank.

I've using a VW tank on my trials special (when I get back to it at least) - I seem to recall there is an issue with ones younger than mine - something in them to absorb something, seal something - some bag of something - the bag fails and dumps crap, grains of something, into the cooling system, blocking matrixes etc.

 

[premmington]

I have to say, and I might have done in the past on another thread, that I don't like that straight hose direct to the expansion tank, clipped to the engine. All engine vibration, movement, gets put into that fitting on the tank.

I've using a VW tank on my trials special (when I get back to it at least) - I seem to recall there is an issue with ones younger than mine - something in them to absorb something, seal something - some bag of something - the bag fails and dumps crap, grains of something, into the cooling system, blocking matrixes etc.

Silca sand bag - takes gel out of G12 antifreeze (bad idea splits and fills up heater matrix)