expansion tanks

[smileypete]

off down the scrappie methinks!

 

Hi,

 

Is it an open/vented system or sealed?

 

cheers,

Pete.

[Big Steve]

An equally important issue with header tanks alongside capacity is the diameter of the connecting pipe, given that air must sometimes pass up the pipe and vent into the tank to achieve this you need a pipe in the order of minimum 25mm diameter.. I notice that very elegant modified fire extinguisher has nice big fittings, the principal is the same whether for heating systems or engine cooling.

 

Some of those plastic ones you can buy in car spares shops are rubbish, with a pipe fitting of no more than 6mm I once seized an engine by not paying attention to this simple rule, got an engine full of air with no way for it to get out.

 

Would have thought big pipe would be quite likely to air lock too,I reckon you need two 6mm pipes, one at the highest point on the engine to let the air/steam! out and one a bit lower in the system so the water will run back. The protoype on my boat, off an Escort van, works a treat and has 2 inputs as standard, but is a bit small so just having a 5L one fabricated. Solderable/braizable radiator cap fittings are available from http://www.nfauto.co.uk/cbs_products_new.htm and some ready made tanks.

[Smelly]

Hello Pete, it's an open system.

 

 

Steve, Car builder's tanks are all a bit small, I actually bought one of their plastic one's but it's obviously got a sealed system in mind and getting a tank fitting into the bottom would still leave me worried about it overflowing, I'm wonderign about putting wo side by side but I'm still taking soundings at the mo'.

 

Anyone any idea, if i've already got the steel, how much a fabricator would charge?

[Smelly]

The man at the fabricator said about 30-35 quid!

 

Althoug I'm still in the market for an extinguisher if I can find it...

[smileypete]

Hello Pete, it's an open system.

Hi,

 

I'd look at making one from a plastic 'lock n lock' type storage box, plus a few tank connectors for bottom inlet, vent and overflow.

 

I've done this for a shower sump strainer and it's worked fine, using silicone to seal the tank connectors.

 

One thing to try and avoid is 'pumping over':

 

http://www.fernox.com/?cccpage=air_in_CHS⊂=3

http://groups.google.co.uk/group/uk.d-i-y/...arch+this+group

 

If you need an air separator they're available from BES (google) among other places.

 

cheers,

Pete.

[gary4lw]

The man at the fabricator said about 30-35 quid!

 

Althoug I'm still in the market for an extinguisher if I can find it...

I got that one when I used to service extinguishers give your local companys a try you might be lucky

[Big Steve]

Hello Pete, it's an open system.

 

 

Steve, Car builder's tanks are all a bit small, I actually bought one of their plastic one's but it's obviously got a sealed system in mind and getting a tank fitting into the bottom would still leave me worried about it overflowing, I'm wonderign about putting wo side by side but I'm still taking soundings at the mo'.

 

Anyone any idea, if i've already got the steel, how much a fabricator would charge?

 

Dunno, a mate who owed me a favour made mine. If it was a simple box, I would have thought £20 for cash, that's based on what my local fabricator has charged me for other jobs. He made me a 4'x2' stainless steel drip tray, including the steel for £30.

 

Only just realised I've posted the link twice on this post, I must be getting old.

 

This tank on e bay looks promising 150184475047

Edited November 22, 2007 by Big Steve