How much coolant will LHS knock sensor drain ?

[Androo]

I just had a look at removing my knock sensors on my V6 VX to drain all the coolant/water.
I reckon I could get the LHS one out but the RHS one looks nearly impossible!
I was wondering if I just removed the LHS would that be good enough to drain the remaining coolant/water from the block, Ie. would I get 6 litres, or only half this amount ?

 

[scrano]

I was gonna point you to a thread that was posted the other day, that was on a similar subject, but then I realized that in the comments for that thread, that you'd already asked this question. One of the guys that did a flush with both knock sensors removed, did suggest that the amount of extra coolant that you'll get out, will depend on how much 'crud' that you remove when you take the knock sensors out. It looks as though the suggestion was, that there was no real benefit too removing the knock sensors, and flushing the system, if you didn't get that built up crud out. If you're willing to do that, then you'll get plenty more coolant out. I'm assuming that if you just do the LHS, then you won't get the full effect, but someone here might be able too better clarify that for me

 

[graham7773]

A year late but that's what happens when you get old. Time just flys by. As to "knock sensors", if yours have not been out before, then when you screw them out you will probably find a plug of rust and other crud that will have to be knocked out with a screw driver or similar. Yes, both sides will have to come out or you may as well not start the job at all. when you finish the job and are refilling with coolant, make sure it is a good one and refill at 50% coolant, %50 demineralized water. I personally prefer to use 75% coolant.

 

[Jxfwsf]

personally i prefer to use the correct ratio and change it at the recommended intervals.... just adding more inhibitor isn't going to do anything except waste more money (change the water tension to a point that even when water itself won't leak..... adding excess coolant will piss out).

Taken 4 years for a VN to finally finish going through the intake manifold gasket and all it's had in that time is tap water after the water pump was replace about 3.5yrs ago (this wasn't neglect, but an experiment) it always went through some coolant with no obvious signs (knew where it was going though) have just driven it to see how long it'd last, was using about 500ml over a few week period but still running perfectly for over a year, finally gotten to the point of using that withing a few days after the years of punishment.

Still runs great though if it's topped up, finally an excuse to turf the 3.8 and drop in a 5.1 (os 308 with efi top end) so it's not all bad

 

[graham7773]

Late post but Engineers must have some reason for using 100% Glycol (coolant/anti-corrosion) in piston engine aircraft. I am guessing that it has a lot to do with reliability? Less chance of the cooling system failing due to corrosion etc? I have owned every Falcon from EA to EL and all of them had cooling system, mainly head gasket, problems due to previous owners being too tight to use a decent coolant, corrosion inhibitor and I am seeing all of the Commodores from VN on having the same problems. Preventive maintenance can save a lot of dollars in the long run.
Re the thread, taking one knock sensor out will leave about 3 liters of dirty coolant in the water jacket.

 

[Pollushon]

Water boils at lower temps, the higher the altitude.

Water and coolant both have properties that compliment each other, which is why manufacturers have recommended mix ratios.

 

[graham7773]

Pollushon, your point is understood but as straight glycol has no water in it, does altitude really affect it? Even if there was water in it, those and todays engines run a pressurized system to raise the boiling point to well over sea level air pressure (boiling point, 212F 100C). Going back in history a bit but the Spitfires and Lancaster bombers of WW2 both used the Rolls Royce V12 engine with straight glycol coolant and were the most reliable engines of the time.

 

[delcowizzid]

Straight water cools better than antifreeze/coolant 20% is plenty of coolant.

Sent from my C8660 using Tapatalk 2

 

[Pollushon]

Pollushon, your point is understood but as straight glycol has no water in it, does altitude really affect it? Even if there was water in it, those and todays engines run a pressurized system to raise the boiling point to well over sea level air pressure (boiling point, 212F 100C).

Hang on, you asked why pressurised liquid cooled piston powered aircraft use straight glycol without water and I answered it. Pressurised liquid cooled aircraft run much lower pressure cooling systems to cars because of the strains it undergoes with altitude (therefore air pressure) changes, which as it climbs increases pressurisation on the system, while outside pressure and temperature decreases.

Some of these craft have a service ceiling of 20k + ft. At 20k ft, water boils at around 70c. Glycol doesn't. So you run a low pressure 100% glycol cooling system and there's far less chance of falling out of the sky. You'd need serious PSI to raise the boiling point of water at that altitude which then cops a shitload of stress when you descend and especially climb, then repeat the process again. You could pop it like a balloon.

That said many, many aircraft run air cooling over liquid because it's not hard to air cool an engine with an IAS of 200kn + running over it. The compromise is HP.

Going back in history a bit but the Spitfires and Lancaster bombers of WW2 both used the Rolls Royce V12 engine with straight glycol coolant and were the most reliable engines of the time.

As did the Hurricane, P38, Mosquito, Typhoon/Tempest, Yak, IL2 and most combat craft of WWII. The Griffon engine reliability had very little if nothing to do with the cooling solution, they were just simplistic, robust and very powerful. That said, a throttle happy pilot could blow one to smithereens if he didn't watch his RPM, torque and mix ratio. They'd also overheat if left idling on the ground for more than 5 minutes. The low pressure liquid cooling was the absolute best solution for such aircraft though, they'd be under full power (or more), zipping, spinning, dropping and climbing constantly.

Short answer, Glycol provides less efficient cooling than water but it's more stable and reliable. Comparing aircraft to cars is beyond chalk and cheese.

 

[Pollushon]

Straight water cools better than antifreeze/coolant 20% is plenty of coolant.

Depends where you live. I do 40- 50% cos Perisher