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Old 25th September 2020, 11:31 AM
Ronin Ronin is offline
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Default Nasty suprise when doing Intake manifold seals

When I replaced intake manifold seals on my 2.8 I found that the whole thing is caked in old sticky oil mixed with sand.. the seals were also perished

Cylinder walls are probably all scored now but I can't tell whether its taking any oil because the engine itself is hemorraging oil from camshaft seals....

Crank breather hose was also all caked up in oil which looked more like tar..
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Old 25th September 2020, 11:47 AM
Regulus Regulus is offline
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Will you do the valley pan gasket as well, while you are in there?
I hope you manage to clean out the old oil and sand.
As I am in a similar process, this can snowball pretty fast, as how much work you need to do.
The cylinder walls might be ok though. Removing the cylinder head will give you a clear view. Any sand that has fallen into the cylinder head might have stayed there, and not fallen deeper into the cylinders. At least that would be my guess.
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  #3  
Old 25th September 2020, 01:07 PM
Ronin Ronin is offline
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Quote:
Originally Posted by Regulus View Post
Will you do the valley pan gasket as well, while you are in there?
I hope you manage to clean out the old oil and sand.
As I am in a similar process, this can snowball pretty fast, as how much work you need to do.
The cylinder walls might be ok though. Removing the cylinder head will give you a clear view. Any sand that has fallen into the cylinder head might have stayed there, and not fallen deeper into the cylinders. At least that would be my guess.
I'm only doing the throttle body and intake seals and also changing the 2 plastic 'spikes' that snapped off as Mikki predicted haha. I'm also re-doing all the vacuum lines and have already changed all the crank breather hoses.
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Old 25th September 2020, 01:22 PM
MikkiJayne MikkiJayne is offline
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Is it actual sand or particles of baked carbon? It does look pretty grim in there but thats not uncommon on the 2.8 because of its terrible crankcase ventilation. The TDIs get very similar looking buildup from the exhaust gas recirculation.

The NA V6 is generally tough as old boots, plus its less susceptible to cylinder damage than the V8 since its an iron block. The only things I've seen happen which can kill that engine are chain tensioners failing or catastrophic overheating.
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Old 25th September 2020, 04:43 PM
Ronin Ronin is offline
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OK after soaking the intake in 10l of brake cleaner the 'sand' turned out to be something else as it turned into sludge but I managed to clean it all off.

I also found this funny looking piece inside which was all dirty so I've cleaned it and lubricated pivot points as well.
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Old 25th September 2020, 04:49 PM
MikkiJayne MikkiJayne is offline
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Ah good news Baked carbon then

That cylinder is the variable length manifold switchover thing. The vacuum pod on the front of the manifold rotates it to make either a long intake tract (good for torque) or a short one (good for power).
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