Heat shield

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markcavman
Posts: 23
Joined: Mon Jul 13, 2015 10:28 pm
Location: Suffolk

Heat shield

Post by markcavman »

I have a really annoying problem with two of my cars,the CDX and the later 16v SRi,they have both developed noisy heat shields,under revs they vibrate because they look like they have come loose.Im sure I'm not alone with this problem and was wondering if anyone knew of a cheap quick fix?
1994 SRi 8v....Sold
1995 SRi 16v
1995 CDX 2.0.....Sold

1996 Calibra 2.0 8v....Sold
1989 BMW E30 Cabriolet
1973 VW Beetle
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Cavalier342
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Location: Dorset

Re: Heat shield

Post by Cavalier342 »

You mean the exhaust manifold head shield? When the ones on my 8valvers used to rattle, I just bent them up slightly, it's only thin metal, obviously do it when it's cold lol. Also try to wiggle the ends and where it comes close to the downpipe to make sure there's no contact anywhere.
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colin1
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Location: Oakdale, S Wales

Re: Heat shield

Post by colin1 »

markcavman wrote:...under revs they vibrate because they look like they have come loose...

...I was wondering if anyone knew of a cheap quick fix?
Am I missing something here? :)
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markcavman
Posts: 23
Joined: Mon Jul 13, 2015 10:28 pm
Location: Suffolk

Re: Heat shield

Post by markcavman »

Sorry Colin1 if I didn't make myself clear......they sound like something is loose i.e. The heat shield is rattling on the down pipe when the engine increases its revs.
1994 SRi 8v....Sold
1995 SRi 16v
1995 CDX 2.0.....Sold

1996 Calibra 2.0 8v....Sold
1989 BMW E30 Cabriolet
1973 VW Beetle
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Robsey
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Location: East Manchester

Re: Heat shield

Post by Robsey »

I found on my C18NZ, that the bolts and location holes corroded very badly until the shield was only partially attached.

Cheap and quick fix is to bend the metal away from anything that it could bang against (As Andrei has suggested).

Or depending how corroded the bolts are.
Remove the old bolts and fit new ones with some big washers (often called Sella washers or penny washers).
markcavman
Posts: 23
Joined: Mon Jul 13, 2015 10:28 pm
Location: Suffolk

Re: Heat shield

Post by markcavman »

Thanks guys.
1994 SRi 8v....Sold
1995 SRi 16v
1995 CDX 2.0.....Sold

1996 Calibra 2.0 8v....Sold
1989 BMW E30 Cabriolet
1973 VW Beetle
colin1
Registered user
Posts: 310
Joined: Sun Jul 12, 2015 10:31 pm
Location: Oakdale, S Wales

Re: Heat shield

Post by colin1 »

I would suggest taking it/them off and stress testing it (bending it around with your hands) for unseen cracks and fractures. If it's sound then refit with new bolts, making sure they aren't too long; it could be battened down as far as it will go but still shy of holding the heat shield firmly in place.

If they're not sound I'm not sure how viable a repair would be in terms of cost, effectiveness and being-bothered-to-do-itness, if you're looking for concourse or thereabouts, I doubt it will be a handsome repair.

How much do those gucci Courtenay ones cost?
93K C20XE Cavalier SRi Hatchback Spectral Blue Metallic
94M X20XEV Cavalier SRi Hatchback Flame Red

96N C14NZ Corsa B 4-dr Flame Red'ish
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Robsey
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Re: Heat shield

Post by Robsey »

Dunno -
But Vauxhall still sell many heat shields for between £29 and £40, dependent upon specific engine or part number.
(Those are current "Genuine Parts Search" prices).

The shields with hot air induction pipe ducts are called "connectors" - how strange.!

Regarding stress testing - sounds a bit extreme for a non structural part.

Normally it is a combination of heat and cack uk weather, which means that the shield mounting holes rot out until they are bigger than the head of the M6 bolts holding the shield in place.

They then vibrate and "flap" about.
More of an annoyance than anything else.

Some shield do crack if left flapping, but again - nothing major will come of it for a long time - depends how long the crack gets. And how long it takes the crack to develop in length.
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