F355 Coolant Rust and Fluid loss.

I'm not an expert by any means so i take your point regarding the possibility of false +ve results on the Co2 test.

Would a cylinder leak down test help..?
Can enough pressure be applied to the combustion chamber to create bubbles in the expansion tank..?

That is assuming its a flame ring burn out, or even pinholes in the cylinder liner..?

 

So I repeated the fluid test today, both on the exhaust and the filler neck.

I ran a hose from the test chamber into the exhaust stream and used rags to divert exhaust gas to bubble through the test chamber and almost immediately, like my breath test yesterday the fluid went yellow.

I brought the vehicle up to temperature, repeated the CCL Test and ran it for 10min.. .. No change in color..

At the end of the test I revved the engine to 3k rpm.. No fluid bubbled up, and the test fluid still did not turn yellow.

You can see how much air is bubbling out of the filler neck in the video @ 10min.( very little)

Again.. I'm no expert but I cannot understand how in the world , if this is a CC leak into the cooling system, that it does not produce a +ve Yellow test..?!!?

Something else must be going on here..?