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nikhurring
By nikhurring | AA Member | 3 Posts | 5 May 2018 at 2:32pm

Hi
Please can you advise if there are recognised industry standard tests for diagnosing a blown head gasket?
Thank you.

Anon
By Cade | AA Expert | 3937 Posts | 7 May 2018 at 8:01am

Hi there,
A test called a "TK" hydrometer test is available to see if a certain type of blown headgasket is evident ie. Combustion gasses passing through the gasket and leaking into the cooling system.
Another test is when compressed air is pumped into the engine cylinders and the cooling system is observed for water level rising or air bubbles.
The nature of the test does depend on the vehicle symptoms and condition, obviously if there is a problem with the vehicle holding water then some of these tests are not very easy to perform, or hard to get a conclusive result.

nikhurring
By nikhurring | AA Member | 3 Posts | 7 May 2018 at 11:02am

Thank you.
So if a stream of airbubbles was seen in radiator and a TK test was positive that is indicative of either a blown head gasket or cracked head?

Anon
By Cade | AA Expert | 3937 Posts | 7 May 2018 at 11:14am

Yes it would be fairly safe to come to this conclusion. A cooling system pressure test while observing for water in the cylinders, or a cylinder pressure test can help confirm this if further proof is required.

nikhurring
By nikhurring | AA Member | 3 Posts | 7 May 2018 at 2:32pm

Thank you.
Your replies are much appreciated!