Lost upper radiator bleed screw...

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ekaftan
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Lost upper radiator bleed screw...

Post by ekaftan »

Hi!

Long time Citroen owner here... I was lost for some years (I sold my XM in 2011) and now got a 2006 C5 Exclusive V6.

I replaced the coolant last week and bled the system using the bleed screw on top of the radiator... and must have left it loose or broken it because today it went missing and I had to plug the hole with a sandwich bag tied with my left sneaker lace to get home.

Anyway... the plug it not available locally (I live in Santiago Chile) and the one I just bought off ebay will arrive in November.

Is it some way to replace if with a large screw or something to have a drivable car in the meantime?

Thanks!
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KennyW
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Re: Lost upper radiator bleed screw...

Post by KennyW »

Did you lose the screw on cap or has the whole bleed screw and cap shear off .

As I did a repair on my Xantia with a tyre valve glued into place.

Kenny
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white exec
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Re: Lost upper radiator bleed screw...

Post by white exec »

If you could post a photo to show where it's missing from, that would help.
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Re: Lost upper radiator bleed screw...

Post by Gibbo2286 »

On my C5 one of the bleed screw is just a plastic screw into the moulded hose. I lost that and replaced it with a winged screw, same size and thread, out of the junk box.
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Re: Lost upper radiator bleed screw...

Post by ekaftan »

white exec wrote:
04 Oct 2021, 20:23
If you could post a photo to show where it's missing from, that would help.
It looks like it was a M10 plastic bolt, with an oring and a large round head.

This is where the screw was...
WhatsApp Image 2021-10-05 at 08.21.13.jpeg
And this is where that hole is in a larger picture (finger is pointing)
WhatsApp Image 2021-10-05 at 08.21.13 (1).jpeg
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white exec
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Re: Lost upper radiator bleed screw...

Post by white exec »

You've got the proper replacement on order, so that's good.
If you think the thread is M10, or something similar, try a few bolts into the hole - without damaging the plastic threads - and if you find one that fits well, use it, maybe cut down in length, with a nut and rubber O-ring to make a seal.

You might find it's not a standard thread, in which case you might have to resort to a rubber cork/bung in there. It will have to withstand the 1.3...1.5bar pressure of the cooling system though.
ekaftan
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Re: Lost upper radiator bleed screw...

Post by ekaftan »

So.... the correct screw arrived and it was not the screw that was broken... it was the radiator itself.

So I bought a couple of these:
w2.jpeg
And JBWelded one to the radiator...
WhatsApp Image 2021-10-13 at 17.21.03 (1).jpeg
I hope it holds :)
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white exec
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Re: Lost upper radiator bleed screw...

Post by white exec »

Hopefully it'll hold. The brass item looks very durable.
The thread of our BX here is M12, but it's in radiator plastic, so could get damaged.
The plastic screw-in plug is in a softer plastic (hard polythene, I guess), so it tends to be the plug that wears.
Only a bleed point, so it won't get a lot of use.
ekaftan
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Re: Lost upper radiator bleed screw...

Post by ekaftan »

white exec wrote:
14 Oct 2021, 08:06
Hopefully it'll hold. The brass item looks very durable.
The thread of our BX here is M12, but it's in radiator plastic, so could get damaged.
The plastic screw-in plug is in a softer plastic (hard polythene, I guess), so it tends to be the plug that wears.
Only a bleed point, so it won't get a lot of use.
Fingers crossed, it survived today's drive to work... 15 minutes of highway/freeway and 20 minutes of stop and go traffic

My other car is off the road since yesterday with a leaky oil cooler and the part is, of course, not going to be here for another week... The joys of living down here...