You mean like this?

 

Exactly! Had the pipe/hose been kept at a nominal temp of (let's say) 10 degrees, that never would have happened irrespective of pressure.

 

There are more possible causes than just heat alone to pipe wear, ECD is another one:
https://ww2.gates.com/australia/brochure.cfm?brochure=7918&location_id=11310

Evans protects against that, so it’s even more a plus for a longer hose life (especially outside the service life).

The temperatures will be the same being it OEM or Evans coolant as I am not going to up the coolant temperature (at least not yet, it’s something for later to study).

Then on top of that, as there is no pressure in the system, I’ll take it that it will slow down the fatigue damage dramatically (constant going from 0 to 1 Bar overpressure). Most important, a small leak will give you time to fix the issue without running the risk of sudden ruptures (due to pressure) that could give more catastrophic damage.

As said, for me this isn’t the main benefit from Evans why I went for it, but a welcome side effect.

Time will tell of course, and am curious to see how it all will develop on my car.

 

Standard coolant also contains additives to protect against ECD.

Let's hope that the cooling system in the S-type has enough capacity to keep temperatures at factory design levels. Gates seems to infer that elevated temperatures are the primary cause of failure. Note that they also make the self-serving recommendation to change all hoses every four years.

 

I think "burst" implies pressure and it's normally a pressurised system. It's done to reduce emissions and improved mpg - neither of which are avos's aims! So long as it works it doesn't need to be pressurised - indeed Brutal has said an STR works with the cap loose.

 

I have read the article carefully, and I take it Gates know that most manufacturers don’t use pure water (or sea water ;-))…

There is some good over capacity available, maybe less if you live in the Middle East desert though, but measuring it is the only way to find out.

Of course temperature has an important role at degrading the pipes, and that is possibly one of the main factors. But there is no discussion anymore if you are not able to conceive that pressure has an important role.

The more I read about this the more the side effect of zero pressure and no corrosion form Evans makes it actually more interesting than I thought before.

 

Having a pressurized coolant system doesn't affect the running temperature one way or the other.

 

The pressure is only there to up the boiling point of the coolant mixture, as water already boils at 100C, and by increasing the pressure and mixing it with coolant the boiling point to 15 psi will be raised to about 120C, giving some good reserve to the system.

You must be below these boiling points, and as you rightfully say, my main goals are increasing the power levels (almost double as standard), and thus also going way outside of the cooling system design. Evans with a higher boiling point of 180C (non- pressurized), will give me some extra reserves, as once a water system (with OEM coolant) starts to boil the cooling capabilities drops dangerously low, risking detonation and other bad things to the engine.

 

A little while back you said "Sorry, I still don't understand why a pressureless system is of any benefit at all".

Given a choice between a pressurized and a pressurieless coolant system, both running at the the same temperature, why would you not choose the latter?

 

Cause I'd gain nothing for my efforts. I don't think any of us have enough years during our short stay on this planet to fix absolutely everything that's not broken in the first place. Having said that, fixing things that are not broken is one step lower on my priority list than spending money to make things different (but not better) much like this coolant.

I seem to fill my schedule quite nicely with things that actually do need attention. That honey-do jar on the fridge never quite gets emptied somehow.

 

In my book the pressurised system IS broken. It's broken by design and I don't like the design. I feel forced to put with its manifest shortcomings. If this other stuff does actually work - and I'm happy to let others try it and measure and report back - I may move to it.

 

If we're getting into the arena of how machines could have/should have been designed, it's pretty easy to find fault. Prioritizing these faults then weighing the pros and cons of proposed solutions would put pressurized cooling systems on the last page of my list.

There's been hundreds of millions of machines built with pressurized cooling systems, not just cars and not just S-types. I think it would be pretty difficult to prove that there's an inherent flaw with the system that can be fixed by reducing the system pressure.

The rate of component rupture is very low to start with. All indications are that multiple heat cycles are the primary cause of degradation with ensuing coolant loss being a symptom. As switching to a pressureless system does not reduce the amount of heat, the root cause has not been addressed. More importantly, the system does not actually become 'pressureless' as there will still be considerable dynamic pressure as the coolant circulates.

Presuming that the potential for coolant loss has been eliminated is incorrect.

 

As hoses age and weaken they will fail much sooner when under pressure.

 

That's possible but they will still fail nonetheless causing loss of coolant and all the nasty side effects. There goes the very expensive waterless coolant and the inability to refill it with water or conventional coolant since the system has been modified to prevent pressurization.

It could be argued that any leaks and loss of coolant on a modified vehicle may only occur at high engine RPM when dynamic system pressure is at it's peak. I prefer finding mine in the driveway after shutdown instead.

I guess some of my skepticism comes from working for several decades on systems with 2500-3000 psi nominal.

15 psi seems much like a f*rt in the wind, so to speak.

 

You wouldn't have had 10+ yr old rubber hoses. I'd rather mine didn't burst and just replacing all of them is beyond me so I'd have to pay a LOT of money to have it done for me. Remind me how many hours labour to do the one under the SC. No thanks. Almost any avoidance path is preferable.

 

It's been an interesting discussion. Like many other forum topics...

Always good to hear from those who try to remove existing constraints imposed by design engineers, manufacturers and existing products.

Good to hear from those who are prepared to spend time and money to test others' ideas, suggestions and products on their precious used Jags.

Important to be reminded that many are happy with the status quo and do not or cannot see any reason for change.

Go for it, Avos, thank you.

 

I hear that sea water mixed with kerosene has tighter water molecules and allows for less hydrodynamic drag on the pump boosting horsepower by 50 percent. This is a miracle!

 

What ya smokin?

 

Next someone will find a new brake fluid based on Aunt Jemimah syrup or transmission fluid based on Bisquick.

 

Also important to understand what appears on the surface to be an improvement may not actually be so- if all other factors are reviewed.

Being that this does not always happens, there's an aftermarket industry out there that fill the shelves at every car parts store with miracle cures.