Thermostat bleed screw

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Oscar25
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Thermostat bleed screw

Post by Oscar25 »

Hi all. This is my first ever post here and I've only owned a T25 for two weeks so far so please be kind! I want to change my coolant as I have no idea how old it is or the concentration and judging by some of the things I've found I'm not inclined to leave it and hope! I've read the wiki about draining, filling and system bleeding and got myself all ready. Checked the radiator bleed screw wasn't seized and tried the thermostat screw...absolutely solid! Not wanting to force it as I read they are delicate, any tips on how to ease/free a seized bleed screw? it's a 1989 petrol 1.9 btw Thanks in advance!

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King Kenny
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Re: Thermostat bleed screw

Post by King Kenny »

Hi Oscar. When I did mine I disconnected a hose from the rear and drained the fluid into a bowl. Sometimes it is better to leave these delicate parts for another day. Good luck.
I don't know where I am, but I'm having a lovely time!

1990 CARAVELLE 1.9cc petrol : watercooled

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kevtherev
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Re: Thermostat bleed screw

Post by kevtherev »

I'll presume this is a late cooling system
If you are really worried just buy a new housing top.
They are not expensive.
I change the coolant every two years and I have forgotten to open the screw a few times with no issues.
AGG 2.0L 8V. (Golf GTi MkIII)

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R0B
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Re: Thermostat bleed screw

Post by R0B »

https://www.brickwerks.co.uk/t3-parts/e ... ative.html" onclick="window.open(this.href);return false;
2.1 LPG/Petrol Auto Caravelle

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Snowmark
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Re: Thermostat bleed screw

Post by Snowmark »

Follow this guide and you won’t go far wrong
http://www.brick-yard.co.uk/forum/bleed ... 29710.html" onclick="window.open(this.href);return false;



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Oscar25
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Re: Thermostat bleed screw

Post by Oscar25 »

Thanks for all your replies. I think before buying a new top I'll try pouring boiling then cold water over it. Maybe the expansion/contraction will free it.

However, I've now noticed a thin-ish pipe off the top of the water pump which ends tucked away behind the header tank and ends with a blanking bolt. Is this a pump driven drainage tube by any chance?

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kevtherev
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Re: Thermostat bleed screw

Post by kevtherev »

No that pump is for a DJ engine with an oil cooler/warmer.
The spigot is generally blocked off on a DG like yours
AGG 2.0L 8V. (Golf GTi MkIII)

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Ian Hulley
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Re: Thermostat bleed screw

Post by Ian Hulley »

Oscar25 wrote:Thanks for all your replies. I think before buying a new top I'll try pouring boiling then cold water over it. Maybe the expansion/contraction will free it.

If you end up swapping the top you would do well to soak the 4 small bolts that hold the thermostat cap on with Plus Gas or similar as quite often the metal threaded inserts spin in the plastic thermostat housing and it's Game Over unless you put nuts and bolts through them. If the stat housing is knackered you have to get the retaining bolts out and they are almost always nasty :rofl

Have fun. Ian. :ok
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Rich D
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Re: Thermostat bleed screw

Post by Rich D »

Just read the advice on draining coolant. I have a similar query. If you drain the coolant by detaching a lower engine hose, do you recall how much you get out? In my manual it says there's 17.5 litres (to get out, for the full coolant swap).

Cheers, Rich D

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kevtherev
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Re: Thermostat bleed screw

Post by kevtherev »

You won't get it all out.
Probably 9 litres.
Easier to flush the old stuff out using a hosepipe
AGG 2.0L 8V. (Golf GTi MkIII)

Rich D
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Re: Thermostat bleed screw

Post by Rich D »

Many thanks for that, Kev. At least I should be able to get over 1/2 the total volume out. Subsequently I will follow your post of 9th April. Quick question . . . is the G12 coolant you use the same as either the blue, or the purple stuff from e.g Just Kampers. . . . no worries if you don't get it from them and don't know!

Cheers, Rich D

1989, 1.9 DG watercooled.

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kevtherev
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Re: Thermostat bleed screw

Post by kevtherev »

Rich D wrote:Many thanks for that, Kev. At least I should be able to get over 1/2 the total volume out. Subsequently I will follow your post of 9th April. Quick question . . . is the G12 coolant you use the same as either the blue, or the purple stuff from e.g Just Kampers. . . . no worries if you don't get it from them and don't know!

Cheers, Rich D

1989, 1.9 DG watercooled.

G12++ or equivilant.
I buy mine from Brickwerks.
It's Never wrong.
I believe Comma sell a cheaper G12++ equivilant.
AGG 2.0L 8V. (Golf GTi MkIII)

Rich D
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Re: Thermostat bleed screw

Post by Rich D »

Kev, I forgot to thank you for your advice, so, thanks, appreciated. I think I will go for the coolant at the end of this season.

Rich D

1989, 1.9 DG petrol, watercooled.

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