Coolant change
Submitted: Sunday, Sep 13, 2009 at 07:55
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Austravel
Hi,
Here's an interesting set of figures. I'm told that radiator inhibitor (diluted in the rad) should range from 7 to 9.5 max as a general rule. Also that the mixture should not change more than 20% from new.
Mine was around 2 years and 9 mths old and around 40,000km. Mostly long k's and probably around 5k max towing a camper. Vehicle is pretty heavy so working all the time and let's say around 10k town or slow work.
I tested Ph a couple of weeks ago and it was 7.4 so decided to change as it appears to be towards the lower end. Turns out the concentrate is only 8.0 and the mixed coolant is only 7.4. That is approx 5l concentrate to 7 litres of
water. So even at the Nissan specified change it's still easily in spec. In fact it looks like you could easily extend it with out any dramas. I'm told from RACQ tech help that many modern vehicles now have a much longer service period for coolant. Some where over 100 mths but many where
well over 6 years. I'm sure with better chemical stability and way better materials in the system this is possible. Would be interesting to know how long it could last in the Patrols. Sure it depends on use and if you do major comps or have major mods or do mostly town work or only short drives it might be different. Though I really do doubt it.
Before you say better safe than sorry etc, etc. The technical data backs this up. It's the same as oil changes in my patrol. I've done a few oil tests and the data shows you can easily get to 7,500km and should get to 10k without any engine dramas. I'm using Dello 400 so not a cheap oil but just shows using synthetics and/or doing early (under 5k) changes is a waste. Again data backs it up, if you want to do it for your own piece of mind then not dramas. However the data tells us that a good mineral oil and 5-7.5k is still fine. Using this regime and baring major failures then the engine will outlast the vehicle
Anyhow just thought you might be interested. Seems as though you can easily get 3 years and above without any dramas to the cooling system. Still it's all up to you of course.
Reply By: Atta Boy Luther - Sunday, Sep 13, 2009 at 08:01
Sunday, Sep 13, 2009 at 08:01
So you want to change the oil every 5000klms but leave the coolant in for years . I power flush and change the coolant every 12 months .
AnswerID:
382932
Follow Up By: Austravel - Sunday, Sep 13, 2009 at 08:55
Sunday, Sep 13, 2009 at 08:55
Great Idea Atta Boy in fact if I was you I'd do it every 6mths.
FollowupID:
650548
Reply By: Robin Miller - Sunday, Sep 13, 2009 at 08:11
Sunday, Sep 13, 2009 at 08:11
The reccomended change period is 4 years in my 4800 patrol , but it checked out ok so changed it at 5 years, more simply because I felt I should rather than need.
AnswerID:
382933
Follow Up By: Member - MUZBRY(Vic) - Sunday, Sep 13, 2009 at 08:14
Sunday, Sep 13, 2009 at 08:14
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FollowupID:
650541
Follow Up By: Austravel - Sunday, Sep 13, 2009 at 08:57
Sunday, Sep 13, 2009 at 08:57
Thanks Robin wonder why the difference between the 4.2 turbo diesel. Or might just be yours is newer so an updated service guide.
FollowupID:
650549
Follow Up By: Robin Miller - Sunday, Sep 13, 2009 at 08:57
Sunday, Sep 13, 2009 at 08:57
Basically driven for last 2 days in some bad conditions like dust so thick across major highways that we almost could not proceed Muzbry, with only a few hours sleep here and there at roadside stops , but surprisingly not as tied as expected - guess thats an advantage of having my wife as second driver.
You can always come up and help me remove dust from every corner of the car.
FollowupID:
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Follow Up By: Robin Miller - Sunday, Sep 13, 2009 at 09:15
Sunday, Sep 13, 2009 at 09:15
I believe it to be because of the alloy head in the petrol Rob.
Most modern petrols specify several years of coolant life.
FollowupID:
650556
Reply By: Member - MUZBRY(Vic) - Sunday, Sep 13, 2009 at 08:12
Sunday, Sep 13, 2009 at 08:12
Gday
I would'nt change the coolant unles it went below 6.5 ph .Below that it is becoming acidic .
How did you check the PH? with tapes or the old swiming pool kit?
Murray
AnswerID:
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Follow Up By: Austravel - Sunday, Sep 13, 2009 at 08:57
Sunday, Sep 13, 2009 at 08:57
With a probe.
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Follow Up By: Austravel - Sunday, Sep 13, 2009 at 09:15
Sunday, Sep 13, 2009 at 09:15
Murray isn't below 7 acidic?
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Follow Up By: Member - MUZBRY(Vic) - Sunday, Sep 13, 2009 at 11:00
Sunday, Sep 13, 2009 at 11:00
Gday Austravel
Yes it is , but there has to be a happy medium, so 6 to 8ph is ok by me. The probe as you use has to be put in a buffer first so the ph meter has a known number to work from.The last time i tried tap
water as a buffer it was 5.25ph . So to be that accurate one must wash the probe and reset in a known buffer medium first.
All this from a person that only changes the coolant when i think it is necessary , or i am going up to the cold country for a drive.
Murray
FollowupID:
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Follow Up By: Member - Keith C (NSW) - Sunday, Sep 13, 2009 at 11:16
Sunday, Sep 13, 2009 at 11:16
G/day Muz, I thought the ph of engine coolant needed to be between 9 &10, I could be wrong,but I remember reading it somewhere Keith C
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Follow Up By: Member - MUZBRY(Vic) - Sunday, Sep 13, 2009 at 11:58
Sunday, Sep 13, 2009 at 11:58
Gday Keith
I have just read the same thing. It said that below 8 is unacceptable and should be 8.5 to 10.
I will have too revise my thoughts.
Murray
FollowupID:
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Follow Up By: Austravel - Sunday, Sep 13, 2009 at 12:42
Sunday, Sep 13, 2009 at 12:42
Muzbry,
Yep calibrated it to a couple of buffers and probe stays wetted in distilled
water. Don't think I need to recal to often but might do so again and retest. Might check tap
water to see if I get the same as you, distilled
water gives me something in the 6's (from memory).
I also read above 8 for Ph however spoke to one of the oil/coolant mobs and they said some of the jap motors have very low ph requirements. Some in the low 6's but can't recall which ones. He said the main thing to check is a drop of 20% below new.
Mine after 30 mths was pretty much the same as this new batch.
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Reply By: Fab72 - Sunday, Sep 13, 2009 at 08:23
Sunday, Sep 13, 2009 at 08:23
Much of what vehicle manufacturers state as suggested service intervals etc, are exactly that....suggestions. At the end of the day, it boils (no pun intended) on the individual vehicle and what tasks it has performed during that service period. Very wishy washy, I know, but that's how they cover their backsides.
As a rule of thumb...I always change my coolant and do a complete flush every 2 years/40,000kms. Probably a bit over zealous but it's cheap insurance considering the cost of a cyilinder head repair. Even the cost of replacing a corroded thermostat housing can out weigh the cost of the coolant.
Just one question. I see you're going to the effort to measure the Ph of the coolant. Are you using a refractometre to ensure you're getting your mixture right? When mixing a concentrate with
water, it's easy to end up with a diluted mixture that because you'll never get all the
water out after a flush (heaps trapped in the heater core etc). It's possible to have a non acidic (ph stable) mixture that's weak. Only a refractometre will tell you if the blend is right.
I general leave the return heater hose off at the firewall while I fill the system. Once the coloured stuff starts flowing out of the heater hose, I then slip the heater hose back on. Has a two fold effect. 1. ensures what's in the system is coolant and not just fresh
water, and 2. prevents the risk of getting airlocks whcih will overheat your engine within minutes of start up.
Hope this helps.......
Fab.
AnswerID:
382937
Follow Up By: Fab72 - Sunday, Sep 13, 2009 at 08:43
Sunday, Sep 13, 2009 at 08:43
Having re-read my post...I apologise for the poor spelling and crappy grammer. It's still early and the fight I got into last night with the Bundy Bear was not won by your's truely.....arrrrgghhh.
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Follow Up By: Austravel - Sunday, Sep 13, 2009 at 09:07
Sunday, Sep 13, 2009 at 09:07
Hi Fab,
I used my boiler test kit which has a Ph meter (TDS and Temp) probe so should be pretty accurate. Only just calibrated it the other day. I don't flush as it uses town
water and don't want mineralized
water in the
tank. I dump what I can out of the radiator, refill with distilled
water, run for 5min and then dump again. Repeat this until
water is clearish. Then tip in 5 litres of concentrate and top up with distilled
water, then go for a 10 min run to mix. So it's
well over the minimum 30% vol by vol mixture.
I still don't get these guys that do
services at half the recommended interval. Nor those that use oils etc that exceed the required specs. It won't make any significant difference and I've yet to see any normal person keep their vehicles beyond 500k. If you do basic servicing with min quality oils etc then baring accidents 500k is easy. For most people this means the vehicle is around 20 years old.
Anyhow just thought it might be of interest to those of us that do servicing as a necessary evil.
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Reply By: Wherehegon - Sunday, Sep 13, 2009 at 13:32
Sunday, Sep 13, 2009 at 13:32
Wifes Toyota which will be 3 years old in December has a sticker under the bonnett saying ""Long Life Coolant""coolant change at 160,000k before a change is due ??. The car has only done 25k in just under 3 years but due to age I will be changing it before the scheduled klms. I change the oil & filter every 5k (petrol), Regards steve m
AnswerID:
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Reply By: Rangiephil - Sunday, Sep 13, 2009 at 17:58
Sunday, Sep 13, 2009 at 17:58
I met a guy with an 80 series petrol at
Millstream Chichester National Park in WA .
His 5 year old "genuine" radiator core had sprung a leak and was a replacement for the original.
He specified ONLY Toyota Coolant and had it changed by the dealer at the specified intervals.
There must have been something else happening for this. My guess is that the dealer just used tap
water to mix the coolant. Or maybe an electrical potential between motor and radiator.
My Range Rover 3.9 "NATRAD" core is now 10 years old and AFAIK still OK using Nulon Longlife changed every 2 years at 50% and only using demineralised
water.
I have never checked Ph but believe that a rigorous maintennce shedule is the key to longevity.
Regards Philip A
AnswerID:
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Follow Up By: Fab72 - Monday, Sep 14, 2009 at 12:46
Monday, Sep 14, 2009 at 12:46
I used to work for a Toyota dealership and the common practice there was to mix Toyota Long Life Coolant with good ole South Aussie tap
water.
At the time, I never questioned this practice, I now know better.
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Follow Up By: Jarse - Monday, Sep 14, 2009 at 20:49
Monday, Sep 14, 2009 at 20:49
"Good ole South Aussie tap
water...." There's the problem :-)
Drinking SA
water reminds me of drinking a house brick. Can't imagine what it does to the insides of your motor :-)
Oops... 'Scuse me!
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Reply By: Member - Kroozer (WA) - Monday, Sep 14, 2009 at 02:02
Monday, Sep 14, 2009 at 02:02
I have just sold my 1990 75 series Landcruiser, still with original radiator. Old girl got a radiator flush every 3 years or so and top up with tap
water and whatever coolant i could find. Had one minor problem 2 years ago with slight crack in bottom
tank, cost $50 to weld up, fine ever since. I am not sure what the big fuss is about using tap
water, i never used Genuine Toyota coolant. Always the green stuff mixed 50/50. 20 years is good service out of a radiator me thinks, and 20 years in one of the hottest towns in Australia. When i replaced hoses and got the
water pump replaced for safety sake, it was clean as inside. No rust at all and only normal grime. I can guarantee you that mechanics dont use de mineralised
water when they flush.
AnswerID:
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Reply By: OzTroopy - Tuesday, Sep 15, 2009 at 10:29
Tuesday, Sep 15, 2009 at 10:29
Whys it called "coolant" ???
Isnt it an anti freeze ... that has side benefits in regards to waterpump lube and corrosion inhibitors.
AnswerID:
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