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C20XE "A.V.A.S" engine mess


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Posted

C20XE Astra GSi

Looking at MOTing and selling the car this week.

These engine are absolutely unbreakable and never had HGF on one.

Oil full of mayonnaise, temp shoots up, coolant reservoir explodes when opened.

No warning, it's been fine but today started up for the first time in about 6 weeks it goes. Last drive was to Derby on AS scrapyard run, which was ages ago and it was fine?

Posted

Hmmm... Doesn't look good.

 

I thought there were two versions of the C20XE head, only one of which is indestructible ?

 

Time for a compression test, perhaps ?

 

Or start looking at SAAB engines on ebay ?

Posted

'COSCAST' from 87 - 89 or so and then the GM ones. They only supposedly go porous around water gallery. Not this bad! Lol

The blocks went the other way, better/'stronger' casing and internals through years.

Posted

C20XE cylinder head gaskets have been known to blow, although they are a tough engine.

 

Yours looks like it has blown.

 

The two heads are Coscast and GM... the Coscast ones are the tougher ones IIRC, identified by "Coscast" on the casting.

Posted

Sounds like head gasket. I have the same engine in my Locost and its got the porous head thing-only symptom is oil in the coolant reservoir. Exploding coolant is not good.

Posted
  On 19/04/2016 at 21:31, fordperv said:

K seal is a bit crap to be fair stixy, steel seal is better

 

 

 

Never used it tbh  but when i get more time i want to test some on a Twincam that blows a lot of bubbles 

Posted

Coolant reservoir will explode when opened whatever the case if it's hot, but that looks like a lot of mayo to me. Was it noticeably losing coolant?

Posted

Not too sure, there is salad cream everywhere! Starting to make me hungry to be honest.

 

There's no turning back now!

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Posted

Have bought all gaskets, belt, tensioner, two pulleys and water and oil pump - I reckon I could get more for it by doing all this, it didn't cost much and took a couple of hours taking everything off.

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Posted

Lovely engines to work on.. It's definitely adding value/ saleability but I'm not sure a stuck 'stat would cause that much mayo at this time of year?

Are you going to have the head pressure tested?

Posted

Thats a good idea, I'd defo get a pressure test done before putting it back together. Doesnt cost very much.

Posted

What would the pressure test do - the block or head, and for what, cracks?

 

It was nice doing this in the sun on the driveway, onto two small torx bolts stripped but came out with a light tap with a chisel. And going against the norm of not spelling any oil any where.

Posted

Usual practice is to pressure test the waterways in the cylinder head - this would show any cracks that could lead to HGF symptoms !

Posted

I guess it would also highlight if your head has gone porous.

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Posted

Yes, as above- the head is tested for internal cracks, which can resemble OMGHGF as the results are similar, mixing of the oil & coolant. Is it a KS head? They did used to go porous due to an incorrect alloy mix as you know.. I would be suprised if it had taken this long to fail though !

Posted

Correct^^. Saves wasting your time. I would be surprised if it is cracked tho.

Posted

The gasket looks original, I had previous troubles with this, rad was leaking, pipes leaked, it overheated a few times (with steam) because it ran nearly dry. Fixed leaks and it was fine without obvious signs, until the other day. I think it just gave up in the end.

I've had one have a pipe explode on NYE in London, I've honestly never had a broken engine, owned seven of these.

 

Watching some ghetto DIY pressure testing on YouTube, think I'll get it checked and possibly skimmed.

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Posted

I rebuilt the head with new cam seals and valve stem seals. Hopefully get it back together tomorrow and then MOTd.

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Posted

Rover V8 engines (especially the bigger ones) sometimes have porosity in the blocks that causes overheating.

 

A pressure test is money well spent.

Posted

Ayyyy, this is more like it. Thanks to the non-raining and not 4 degrees weather today, I continued my lil rebuild of the GSi engine.

So with my snooker chalk in my pocket, I torqued the head down ,made a gasket for the inlet, and set the tension on the cam belt. I was sent the wrong belt but the old one looks new, which is a bit of a blow out after all the new stuff bought, but after spending 2 hours setting the tension, I think I'll be happy with it.

 

Everything is spotless all cruddy oil on the head, block and crevices is gone and cleaned out. I set the cam cover on fire for 5 minutes which made it easier.

 

Newly painted cam and belt covers make the whole engine bay look superb.

Only thing left now is flush through with cheap oil, fix the wiring loom, fit the new ECU, fit new sump, repair the mess up on the interior computer (speed sensor and fuel computer is random which I think is a wiring problem), and find half of the nuts/bolts I've mislaid and then MOT it and sell it.

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Posted

Did you get it pressure tested or skimmed station? whats the cost of that these days 

Posted

Nice work! But unless you've found a very obvious breach in the head gasket between an oilway and a water jacket, I think you may be disappointed after an hour of it running? :?

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