Vacuum testing a cylinder head for leaks

[Davezj]

Here is a video of my vacuum test rig i have designed and made to test cylinder heads.
this test rig will check inlet and exhaust valves for leaks and test the cylinder head for cracking.

here is the video.

It is a youtube link but it is my limited channel.

https://www.youtube.com/watch?v=e1MdSnNp8v8

tell me what you think of my design.
i know you can put a cylinder head on its side and fill the exhaust and inlet ports with fluid to see if leaks past the valve seats. but it is a very basic test. this vacuum test rig gives a good indication of how bad a pair of valves seats are and it also checks to see if the head has any cranks in it.

the valve tests pulls a vacuum in the direction of the intended seal direction, e.g. the valve will be pressed against the valve seat as it would when a combustion event occurs.
the cylinder chamber test pulls a vacuum against the intended direction of the valves as it creates a vacuum in the chamber. but this test is designed to check for cracks in the head. So a slight increase in the leak rate is to be expected but only slight increase.
in all of these vacuum tests you are looking for a major difference between maintaining a complete vacuum and loosing it very quickly which indicates remedial work is required on the valve seats the valve guides or suggest the head is scrap in the event of a cracked head.

My intention is to remove all the valves in this head and do a mild valve seat regrind. Then retest the head and hopefully it will show perfect seal on all valves. i will have to wait and see.

One modification I could make is to create a couple of blank plate to block off the inlet and exhaust valve ports while doing the chamber test to give a better indication of chamber integrity.

That would be a more complete test.