Vauxhall Astra G Petrol (1998 - 2004) - 03 1.6 8v. Brown Sludge in the Filler cap

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Sun 2 Dec 2007 15:22
03 1.6 8v. Brown Sludge in the Filler cap - Rallyman70
Hi, I have noticed brown sludge in the filler cap of my 2003 Astra 1.6 8v petrol. There is no sign of extra coolant usage, infact I've never had to top up the coolant and the dipstick shows only normal condition of the oil. I have not noticed any decline in performance and I use 10w50 10w/40 oil ## of a good quality. The engine has covered 43000 miles. My question is, can there be any other reason for this brown sludge other than Head Gasket? Any ideas or advice gratefully recieved. Thanks.

## {typo amended - see futher down-DD}

Edited by Dynamic Dave on 02/12/2007 at 18:12

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Sun 2 Dec 2007 15:41
03 1.6 8v. Brown Sludge in the Filler cap - Screwloose
10W-50? In an '03 Astra? Whose? What is the API rating on the can?

Edited by Pugugly {P} on 02/12/2007 at 16:05

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Sun 2 Dec 2007 15:46
03 1.6 8v. Brown Sludge in the Filler cap - Ruperts Trooper
The 1.6 8v, particularly in the Astra, has a reputation for "mayonaisse" (emulsified oil) on the filler cap and dipstick - my theory is because it's overcooled - the frontal air intake is the same size as the 200bhp turbo. Overcooling allows condensation from engine blow-by and atmosphere, particularly at this time of year.

Vauxhall recommend 10W-40 ACEA-A3 oil, your 10W-50 is incorrect www.vauxhall.co.uk/vx/owners/engineoils.do#Astra

Remove the sludge, give the engine a good run to get rid of condensation and block the lower grill, but don't forget to remove the blanking in spring. Don't block the upper grill, the engine intake is there and you'll need some cooling.

Edited by Pugugly {P} on 02/12/2007 at 16:06

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Sun 2 Dec 2007 16:18
03 1.6 8v. Brown Sludge in the Filler cap - Rallyman70
Sorry, my mistake, it is 10w40 Quartz oil.
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Sun 2 Dec 2007 17:10
03 1.6 8v. Brown Sludge in the Filler cap - Ruperts Trooper
Glad it was just a typo...
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Sun 2 Dec 2007 19:28
03 1.6 8v. Brown Sludge in the Filler cap - Rallyman70
By the lower grill I take it you mean under the number plate?
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Sun 2 Dec 2007 21:36
03 1.6 8v. Brown Sludge in the Filler cap - Ruperts Trooper
That's the one.
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