1.8t hgf

[amblegrumpy]

Hi,
I do apologise for crashing in on your article "1.8 hgf" - I had the intention of posting my bit on the main page and managed, as you saw, to dump it in your answers (I really shouldn't let my carer go home so early, or better yet - at all!). I'm not very good with confusers...
But I can tie my own shoelaces.
Sort of.....
All the best.

[kaiser]

Ha ha, don't worry.
The good thing about a forum like this is that there is plenty of space!
So I think a couple of you "?grumblings" can easily be fitted in.

[kaiser]

Early days, I know, but the neat AF solution and even the 50/50 mix behaves differently from the water sample.
In the picture you see many small bubbles in the water sample, hardly any in the mix, and none in the pure sample.
Time will tell!

[T-Cut]

Probably just surface tension and air solubility differences. The straight water is de-aerating like tap water does on standing in the warm. I think steel requires some water present to set up a corrosion reaction.
I'm more intrigued by the colourless antifreeze. What type/brand is it? They're usually dyed to indicate the inhibitor. It's not just glycol is it? That would explain it.

TC

[kaiser]

Originally Posted by T-Cut

Probably just surface tension and air solubility differences. The straight water is de-aerating like tap water does on standing in the warm. I think steel requires some water present to set up a corrosion reaction.
I'm more intrigued by the colourless antifreeze. What type/brand is it? They're usually dyed to indicate the inhibitor. It's not just glycol is it? That would explain it.

TC

I have asked the manufacturer for the technical information, let's see if they come back.
It is from a chemical company here in Johannesburg, where we also buy other products. Some of which are excellent and some of which are just average. The colour was originally far more yellow, but the drum lives outside and is at times subjected to heavy sunshine.

The sun here can make everything fade very quickly.!

If you look into the radiator of my P5, it is very green.

[T-Cut]

So it's a standard antifreeze system. The inhibitors in it should have prevented the rust/corrosion that's apparent in your photos. Since the sun has degraded the fluorescent dye one has to wonder whether it's also degraded the inhibitors. If you leave the experiments to run a few weeks/months, perhaps you'll find the answer.

TC

[kaiser]

Originally Posted by T-Cut

So it's a standard antifreeze system. The inhibitors in it should have prevented the rust/corrosion that's apparent in your photos. Since the sun has degraded the fluorescent dye one has to wonder whether it's also degraded the inhibitors. If you leave the experiments to run a few weeks/months, perhaps you'll find the answer.

TC

That is what I intend to do, and I am sure I will.
But don't forget the coolant in the system would have been there for a year or so. That means the last years influence on the antifreeze would not have affected the stuff in the radiator.
However UV is notorious for affecting colours, I don't know if it would affect the efficacy of chemicals to the same extent.

[barry]

Kaiser
Just a thought regarding your HGF problem. I once had a Singer Vogue which twice ended up with HGF. In addition the original head and one replacement cracked between the two centre cylinders after several attempts to rectify the failure. In the end it was neccessary to replace the engine due to the water ingress into the cylinders.
The third cylinder head after surface grinding was fitted to the replacement short block. The block itself had been resurfaced on its top face. This engine and cylinder head never gave any more trouble which led me to believe that the original block top surface was not true, possibly distorting the cylinder head under torque.
Sorry to be long winded but thought it may be worthwhile if the head is removed again for the block to be checked for trueness although the visual signs in your case are indicating something quite different at this stage.
Barry

[RodgerD]

Originally Posted by barry

Kaiser
Just a thought regarding your HGF problem. I once had a Singer Vogue which twice ended up with HGF. In addition the original head and one replacement cracked between the two centre cylinders after several attempts to rectify the failure. In the end it was neccessary to replace the engine due to the water ingress into the cylinders.
The third cylinder head after surface grinding was fitted to the replacement short block. The block itself had been resurfaced on its top face. This engine and cylinder head never gave any more trouble which led me to believe that the original block top surface was not true, possibly distorting the cylinder head under torque.
Sorry to be long winded but thought it may be worthwhile if the head is removed again for the block to be checked for trueness although the visual signs in your case are indicating something quite different at this stage.
Barry

It's an aluminum block with spun cast steel cylinder liners with the two metals expand at different rates. The liners should be around 0.004" higher than the block when cold, which results in them being flush at operating temperature.

A lot is going on, thermal expansion of dissimilar metals, possibly electrolytic corrosion or cavitation. The original HG was a single sheet gasket with perimeter elastomer seals and a flame ring with a multi-layered gasket being an improvement. Its fitment only recommended if liner heights are within specification. Just checking that a block face for 'trueness' isn't sufficient.

[kaiser]

Well, that developed rather quickly!

the antifreeze does work, that is already clear.
I have checked the three bottles with liquid, and there are clear signs of rust in the pure water sample, after just one!! day.

Nothing whatsoever in the two other bottles with neat and 50/50 solution.

(I have turned the bottle with clear water for a better view of the nails)

Now the question remains, why does the fire ring get consumed by rust, even if the liquid seems to protect?. It must then be associated with the combustion, maybe suggesting that the rust is a result of the fault somehow and not the reason for it. In other words it might be the symptom rather than the cause?