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Coolant resevoir tank
Posted: 19 Apr 2016, 12:26
by pleasestartnow
Hi all
Getting the van ready for this years adventures and just noticed that the reservoir, the one behind the number plate, is not connected to anything. So the coolant I put in there day 1 is still there, I usually just check the expansion tank and the coolant there is fine no hassle. But there is no piping connecting them? The area where the piping would have come from on the reservoir is capped off and I cant see where I would connect to on the expansion tank. Any idea why this would have been done and should I re connect piping?
Cheers
Re: Coolant resevoir tank
Posted: 19 Apr 2016, 12:41
by kervinmervin
Hello, this is the pic for my DG engine, maybe different depending on your model, 2 being the reservoir behind the number plate flap. The coolant in 5 (expansion tank) pushes out into the reservoir (2) when hot through the dalek cap/valve, then sucks back in when cooling. The expansion tank should be full to the brim (5). Picture from
http://www.vagcat.com" onclick="window.open(this.href);return false; great resource for all parts.
K
Re: Coolant resevoir tank
Posted: 19 Apr 2016, 12:50
by pleasestartnow
Cheers for that appreciate it, I will double check again tonight when I get home but on mine, on the reservoir where tubing (9) is connected is blanked off. It goes from the top of the expansion tank with the 5a style cap to the engine. Will get a picture up when I am home so people can see.
Re: Coolant resevoir tank
Posted: 19 Apr 2016, 15:24
by Ant-t
That is why your reservoir isnt working as expected, they need to be connected up to feed each other as the coolant expands/contracts
Re: Coolant resevoir tank
Posted: 19 Apr 2016, 18:13
by pleasestartnow

Here is a picture of the expansion tank on the right with the tubing running from the cap to the engine. So there is 2 pipes coming from that tank to the engine.
Picture if the reservoir capped off.
Re: Coolant resevoir tank
Posted: 19 Apr 2016, 23:25
by RogerT
I think there should be a thread where we try to trump each other with the bizarre things we have discovered that previous owners/mechanics have done.
I think your disconnected coolant tank trumps my missing coolant tank, but I did have an LDA on my JX with the input hose connected to a bolt stud on the waste gate!
Sorry, that wasn't a helpful contribution to the original thread...
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 06:07
by kevtherev
Now why didn't VW think of that!
Oh I know, VW fitted two connected tanks so the pressure inside the cooling system remains constant, and doesn't escalate to compromise the joints, seals and gaskets.
Best sort that out chap.
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 07:03
by pleasestartnow
Cheers everyone for responses I appreciate that. Thanks kevtherev, that actually makes sense alright. No action necessary so, onwards to the next issue.

Re: Coolant resevoir tank
Posted: 20 Apr 2016, 07:12
by R0B
No action necessary? You need to connect both tanks fella.
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 07:15
by ghost123uk
Yes, "pleasestartnow", I think you missed the humour in Kev's reply.
Get it back the way it
should be asap, or you may end up looking for a new cylinder head, or worse

Re: Coolant resevoir tank
Posted: 20 Apr 2016, 07:22
by Ant-t
Can't understand why someone would disconnect the two tanks, maybe the PO didn't understand the cooling system?
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 08:23
by kevtherev
Ant-t wrote:Can't understand why someone would disconnect the two tanks, maybe the PO didn't understand the cooling system?
Clearly..

Re: Coolant resevoir tank
Posted: 20 Apr 2016, 10:51
by pleasestartnow
Eek sorry. So from the expansion tank cap to the reservoir no bother. But what about where the expansion tank cap is connected to now what is that for? I only noticed it yesterday but its been like that for the last year and no issues, I agree that the two tanks should be linked but I would like to understand why its connected the way it is now and if I can just cap off where that tube was going to the engine.
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 12:54
by Ant-t
So where is it connected? Trace the pipe and post up your findings
Re: Coolant resevoir tank
Posted: 20 Apr 2016, 13:41
by pleasestartnow
So as you can see, the thinner bit of hosing that I would have thought to be piped to the reservoir and the large bit of tubing both going to the same part on the engine.