[Mk2] [Generic] Best/safest way to loop heater lines?

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SonicSW20
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[Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

It just doesn't end... Car is leaking coolant from above the fuel tank, must be heater lines. Tank out to replace those obviously, which will be happening to replace the fuel pump.

In the mean time, what is the safest / best way to either loop the lines, or clamp them?
shinny
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Location: Reading, UK

Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

Personally, I'd get a couple of 19mm plugs and block them off.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Is plugging the lines on the coolant tree / hard line safe compared to looping? If so that's a simpler solution for sure.
shinny
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

Gazza_DJ wrote:Is plugging the lines on the coolant tree / hard line safe compared to looping? If so that's a simpler solution for sure.


Well, I'm thinking about your cooling system... if the heater is set to cold, the lines are effectively plugged anyway. If you loop them, you've essentially doubled the size of your bypass pipe, increasing the path of least resistance that avoids the radiator at the front. The car will probably be fine with less coolant flowing through the rad as the SW20 is overcooled as it is... but why risk finding out in this hot weather?

And yes, I have done this myself, albeit not for long as I re-diagnosed my issues as a bad banjo bolt rather than the pipes from hell.

It's of course up to you where you choose to block. I happened to have two 19mm alloy plugs floating around, so I plugged the two rubber hoses where they would normally join onto the PfH. I see no issue with clamping a 19mm silicone cap onto the coolant tree and heater return pipe instead.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Cool, so I could just get a couple of appropriately sized plugs , jubilee clips and just disconnect at the hard lines in the engine bay and plug there? That would keep it simple.

19mm is the ID of those hoses?
pbmr2
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by pbmr2 »

yeah 19mm ID
shinny
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

Gazza_DJ wrote:Cool, so I could just get a couple of appropriately sized plugs , jubilee clips and just disconnect at the hard lines in the engine bay and plug there? That would keep it simple.

19mm is the ID of those hoses?


Correct :thumleft:
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Thanks both. Seems to be the simplest solution to me for now.

Can you think of anywhere that would stock this kind of thing today? The express delivery charges I'm seeing on eBay for the first few products are a bit mad!
shinny
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

It may sound crazy, but try an aquatics shop. 19mm ID is a very common size for aquarium / pond supplies so they may have a bung (probably plastic) on the shelf.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Will give one a call. Seen this on B&Q's website, doesn't look like there's enough meat on it to get a good clamp / seal as it's threaded - http://www.diy.com/departments/plumbsur ... 682_BQ.prd
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

alanmr2turbo wrote:how about this place

http://www.autosiliconehoses.com/silico ... plugs.html


They are the ones I've seen on eBay, super long estimated delivery times and want silly money for a faster service.

Found another one that should get here by Wednesday. Just need to grab a couple clips from Halfords or something.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Capped for now - what is the best way to fix the problem? Cut the hard line and replace the damaged section with hose or replace the whole line with hose?
shinny
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Location: Reading, UK

Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

The solution I've seen is to run 2x19mm hose under the fuel-tank and bypass the hard pipes entirely. Beats dropping the tank... but you're doing that anyway! So maybe run the hoses above the tank? I'm not so sure about chopping out part of a hardline and creating an inaccessible joint above the tank - sounds like a bad idea to me.

Just spitballing here, but I have been considering another idea on this too, although I'm unlikely to try it myself. For background, I'm currently thinking about a coolant system simplification when I reshell which would see me fitting a Davis Craig Electric Water Pump, removing the thermostat (because the EWP controls the flow / temperature), teeing the heater matrix off the radiator at the front of the car and then using the heater pipes for my chargecooler pipework (plus a number of other things that aren't relevant to this post). Now, teeing both sides of the heater off the coolant rad makes no sense for a car with a thermostat because flow through the heater would be limited by the stat in exactly the opposite way to what you'd want. However it did make me think that you could tee the input to the heater matrix off the rad's input and send the matrix's output through the remaining good hardline (AFAIK only one pipe goes bad) and plumb that back into the engine as normal. I suspect it would have a slightly detrimental effect on heater performance, but might be a path of less even resistance than running pipework under the car. Well, other than the need to partially drain the main coolant system to avoid dropping about 5L of coolant into the frunk when you break into the radiator pipework.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Someone on Facebook mentioned a couple of people (Lee I think?) take their heater matrix feed from the main coolant lines in the frunk... downside is it takes longer to heat up.

Freeing up those hard lines for a chargecooler does sound like a nice solution.
shinny
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Location: Reading, UK

Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by shinny »

Gazza_DJ wrote:Someone on Facebook mentioned a couple of people (Lee I think?) take their heater matrix feed from the main coolant lines in the frunk... downside is it takes longer to heat up.

Freeing up those hard lines for a chargecooler does sound like a nice solution.


I'd love to know where they teed from!

I still think I'd run a separate line back given the option (assuming a 'stat is present). Otherwise a closed 'stat would mean no heater, which presumably is more likely in the winter when your radiator is doing a better job of cooling the coolant and you want the heater more.
SonicSW20
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Re: [Mk2] [Generic] Best/safest way to loop heater lines?

Post by SonicSW20 »

Let me see if I can find the post, I'll tag you :thumleft:
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