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[Craig_R]

should i get a compression test to make sure its the Head Gasket ?

Would the compression test be done on the coolent system ? or on the pots throught the spark plug holes ?

Craig

[Markjay]

should i get a compression test to make sure its the Head Gasket ?

Would the compression test be done on the coolent system ? or on the pots throught the spark plug holes ?

Craig

Testing for failed head gasket:


a. Cylinder compression test:

If you run a compression test and find that one or more cylinders show considerably lower compression then the others, there are three main reasons: bent/burnt/leaky valves, excessive wear on cylinder compression rings, or failed head gasket.

Drop a spoonful of engine oil into the low-compression cylinder(s) though the plug hole and repeat the test. If compression now goes up, the problem is with the compression rings. If the compression remains low, the problem is with the head gasket or valves.

(Incidentally, if two adjacent cylinders show low compression, there is a good chance that the head gasket failed at the connection point between the two)

b. Cooling system pressure test:

This is done by pressurising the cooling system through the expansion bottle, then monitoring the pressure on a pressure gauge for few minutes. The cooling system is sealed so the pressure should be maintained. If the pressure goes down, there is a fault in the cooling system – which could be either just a normal a leak or a faulty head gasket.

c. Exhaust gas analyser:

By far the most conclusive test for a failed head gasket is checking for exhaust gasses in the expansion bottle when the engine it running. Can be done at MOT testing station by lowering the analyser into the expansion bottle (but not into the coolant).

d. Anti-freeze in exhaust fumes:

Also, if you see water droplets forming on your hand when placed behind the exhaust and can smell anti-freeze, it points quite conclusively to a head gasket failure.

[Craig_R]

c. Exhaust gas analyser: is the winner if its the best test Ill have to find a MOT place to get it donr I only need to find the time now Lucky I dont really need the Car for 3 to 4 weeks so that should give me some time to get the repairs done.

Thanks markjay

Craig

[Craig_R]

Ohhhh One more thing Is it Strange for an engine to have a failed Head Gasket with only 67,000 miles on it ?

Craig

[Auto Addict]

I would have thought that the only thing to make a head gasket blow after that mileage is that at sometime the engine must have seriouly overheated.

But that's only my opinion, don't take it for gospel.

[Markie]

Ohhhh One more thing Is it Strange for an engine to have a failed Head Gasket with only 67,000 miles on it ?

Craig

omega engines as a whole are very reliable and despite there issues hgf is not one of them - certilnly the v6`s are bombproof and the 4 pots not far behind at all. Vauxhall as a whole are pretty good in this area compared to Rover or Fiat for example.

So yes, as an Omega, its rare, in fact i think i hae only heard of one other omega hgfailure  

[TheBoy]

Lack of maintenence can prematurely ruin HG, esp if coolant not changed regular...

[Markjay]

The gasket itself rarely fails, certainly at this mileage.

If the cooling system was running on hard water with little or no anti-freeze, or if the anti-freeze was left in the system for a few years without changing/flushing, you could get corrosion developing around the waterways in the alloy head. Eventually the head’s mating surface become slightly pitted, and allows gasses to escape into the water passages and vice versa. However the alloy on the Omega heads is good quality (unlike some Italian engines..), and will take some abuse before actually corroding.

The other possibilty is if the engine seriously overheated at some point of time. When the head heats-up it expands and this is taken into account when designing the head and bolts. However if it seriously overheats, the head tries to expand further, but being limited by the head bolts this causes the lower mating surface to 'warp' and become uneven - and then gasses can escape around the head gasket.

When you look at a head gasket that came out of the engine, you will often see that it is badly damaged at one point - but keep in mind that once hot exhaust gasses are blowing past it it is likely to burn and the hole will increase - so a damaged head gasket is no proof by itself that the fault occurred because the head gasket failed first, it is quite possible that the actual damage to the head gasket occurred after the head was blowing past it because it overheated etc.

In short, head gasket failure on properly maintained Omega engines is very rare...

[Craig_R]

Thanks For All this Advise Guys Your all very kind

Well I dont know if it was looked after before i got the Car Guess thats the problem with 2nd Hand Cars, But All Of the Breathers Were in a bad way and the Throttle Body Until I cleaned them all Out.

Well Once I get my Meega along to a MOT garage and find out if it is the Head Gasket, This Car is going to have lots of Love and attention Shame I dont have a Garage to clean and give her love and attention i would like to on these dark nasty nights in the cold

Craig

[Markjay]

Thanks For All this Advise Guys Your all very kind

Well I dont know if it was looked after before i got the Car Guess thats the problem with 2nd Hand Cars, But All Of the Breathers Were in a bad way and the Throttle Body Until I cleaned them all Out.

Well Once I get my Meega along to a MOT garage and find out if it is the Head Gasket, This Car is going to have lots of Love and attention Shame I dont have a Garage to clean and give her love and attention i would like to on these dark nasty nights in the cold

Craig

Exhaust gasses detector:

http://www.tooled-up.com/Product.asp?PID=134147

A bit pricey but should give a definite answer....

[Craig_R]

Well Just Had My Coolent System Checked with the kit markjay said about but lucky i never had to pay for it a Mechanic Guy I know had a test kit and It Turned YELLOW From Blue meaning Yep its the Head Gasket has Gone Boooo

He is going to do all the Work this Week For me at £375 including skim and all the bits not to bad i think


Thanks For all the Help On this Problem

Craig R