Recent Topics
Ford 4.6L Durability?
by Auae85
06/20/18 11:00 PM
Mercedes Benz High Mileage Badges
by Snagglefoot
06/20/18 10:46 PM
Lawn Tractor Tire Sealer
by 97K15004WD
06/20/18 10:01 PM
Fireworks Stores
by Warstud
06/20/18 09:36 PM
1994 Ranger fuel tank/frame cleanup & NOS part
by 01rangerxl
06/20/18 09:27 PM
Koreans top J.D. Power qlty; Ford, GM, FCA make strides
by wemay
06/20/18 09:18 PM
How Fast to Run a ZeroTurn Mower
by Gebo
06/20/18 09:10 PM
Bosch 3300 C&P Yamaha FZ-07
by bmwpowere36m3
06/20/18 08:49 PM
My FIL in hospice
by fdcg27
06/20/18 08:41 PM
Spraying Polyurethane
by Texican
06/20/18 08:37 PM
Dehumidifier icing
by Kestas
06/20/18 08:37 PM
Diesel lube in Petrol Engine
by Ducked
06/20/18 07:46 PM
New key programming cost
by 92saturnsl2
06/20/18 07:27 PM
When you help someone and its time to walk away
by RazorsEdge
06/20/18 07:09 PM
Sightly overfilled oil..ok or drain?
by flinter
06/20/18 07:08 PM
Wheel says 50 mph max
by pda1122
06/20/18 06:54 PM
15w40 Maxlife in Motorcycle
by Brian553
06/20/18 06:39 PM
BITOGer in Ottawa/Orleans Canada area ? ...
by Papa Bear
06/20/18 06:36 PM
Old Engine SOUND
by MasterSolenoid
06/20/18 06:06 PM
ProMotive PH 2500 CUT OPEN
by car51
06/20/18 04:54 PM
Newest Members
yamahaboy125, Turboholic, TrpNY, bcj, Ilia
65282 Registered Users
Who's Online
25 registered (citationxeleven, Char Baby, clinebarger, Black, bbhero, ctechbob, 2 invisible), 902 Guests and 34 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
65282 Members
67 Forums
285683 Topics
4767761 Posts

Max Online: 3590 @ 01/24/17 08:07 PM
Donate to BITOG
Page 1 of 3 1 2 3 >
Topic Options
#4243778 - 11/07/16 10:41 AM Why does radiator coolant need to be replaced?
veryHeavy Offline


Registered: 11/04/16
Posts: 479
Loc: MN, CA
My car passed 60,000 which means I need to flush the coolant.
But why?
It still looks nice & green. It feels like I should be able to run to 120,000 since the radiator still continues to keep the engine from overheating. What exactly happens to coolant that it requires replacement after 60000 miles of usage?


Edited by wwillson (11/08/16 05:14 AM)
Edit Reason: subject spelling

Top
#4243784 - 11/07/16 10:45 AM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
supton Offline


Registered: 11/09/08
Posts: 11948
Loc: NH
The corrosion inhibitors give up. What mechanism that is, I dunno (what wears or gives out). But due to the dissimilar metals in the system, once those inhibitors go, so does precious metal.
_________________________
2011 Toyota Camry, base, 2.5L/6MT, 162k, hers
2010 Toyota Tundra DC, 4.6L/6AT, 143k, ours
1999 Toyota Camry LE, 2.2L/4AT, 183k, his

Top
#4243791 - 11/07/16 10:50 AM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
bubbatime Offline


Registered: 03/18/08
Posts: 5622
Loc: South Florida
It lubricates the bearings in the water pump. Those "lubricants" wear out over time. The PH level, or acidity, also changes over time, so you want to get the old stuff out and replace so it doesn't corrode.
_________________________
17 Chrysler Pacifica Mobil 1 5W30
13 Yamaha XT250 Valv MC 10W40
12 Suzuki S40 Rotella 15W40
10 Acura TSX 2.4 PZL Plat 5W30
06 GMC Sierra Nextgen 10W30



Top
#4243822 - 11/07/16 11:12 AM Re: Why does radiator coolant need to be replaced? [Re: bubbatime]
kschachn Offline


Registered: 12/26/05
Posts: 9395
Loc: Upper Midwest
It doesn't in any of my cars, and I've yet to see one where it does. A water-glycol mix is not a very good lubricant, every time it has migrated past the seal into the bearings it has caused them to fail in short order.

Originally Posted By: bubbatime
It lubricates the bearings in the water pump. Those "lubricants" wear out over time. The PH level, or acidity, also changes over time, so you want to get the old stuff out and replace so it doesn't corrode.
_________________________
1994 BMW 530i, 227K
1996 Honda Accord, 262K
1999 Toyota Sienna, 394K
2000 Toyota ECHO, 267K

Top
#4243835 - 11/07/16 11:26 AM Re: Why does radiator coolant need to be replaced? [Re: bubbatime]
69GTX Offline


Registered: 09/23/15
Posts: 3815
Loc: Connecticut
Originally Posted By: bubbatime
It lubricates the bearings in the water pump. Those "lubricants" wear out over time. The PH level, or acidity, also changes over time, so you want to get the old stuff out and replace so it doesn't corrode.


With the advent of mechanical seals in water pumps I thought that "lubricating" seals/bearings was no longer applicable.
_________________________
----------------

2001 Lincoln Cont 4.6L DOHC/ 39K mi / QS HM 5w30 / FUG XG2
1999 Camaro SS M6 /19K /Mobil 1 0w40 /Fram UG /GM MTL-ATF
1969 Ply GTX/RRs

Top
#4243894 - 11/07/16 12:24 PM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
HerrStig Offline


Registered: 08/24/11
Posts: 9560
Loc: Boston, MA
Originally Posted By: veryHeavy
My car passed 60,000 which means I need to flush the coolant.
But why?
It still looks nice & green. It feels like I should be able to run to 120,000 since the radiator still continues to keep the engine from overheating. What exactly happens to coolant that it requires replacement after 60000 miles of usage?
Anyone who waits until the engine is overheating to change coolant is crazy. You you wait until your tires blow out before you change them/

Top
#4243907 - 11/07/16 12:37 PM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
Donald Offline


Registered: 03/21/04
Posts: 20455
Loc: Upstate NY
Originally Posted By: veryHeavy
My car passed 60,000 which means I need to flush the coolant.
But why?
It still looks nice & green. It feels like I should be able to run to 120,000 since the radiator still continues to keep the engine from overheating. What exactly happens to coolant that it requires replacement after 60000 miles of usage?


Drain and refill. No need for a flush if things look good. The additives wear out. Drain and refill is cheap compared to parts replacement.

Use the proper coolant and distilled water.


Edited by Donald (11/07/16 12:38 PM)
_________________________
2015 Subaru Forester 2.5 engine/CVT
2015 Ford F250 w/Powerstroke
2016 Subaru Crosstrek CVT (wife's)


Top
#4243915 - 11/07/16 12:44 PM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
nthach Offline


Registered: 01/02/04
Posts: 3895
Loc: California
The add pack in coolant(mostly corrosion inhibitors) breaks down after a while - more so with conventional green coolant than the OAT(Dex-Cool) and hOAT(Japanese coolants with phosphates, silicated hOAT like G-05/G-40/G-48) coolants used by the OEMs these days.

In rare cases does glycol break down to glycolate - and game over if that does.


Edited by nthach (11/07/16 12:44 PM)

Top
#4243962 - 11/07/16 01:37 PM Re: Why does radiator coolant need to be replaced? [Re: bubbatime]
Chris142 Offline


Registered: 06/05/03
Posts: 16819
Loc: Deplorable in apple valley, ca
Originally Posted By: bubbatime
It lubricates the bearings in the water pump. Those "lubricants" wear out over time. The PH level, or acidity, also changes over time, so you want to get the old stuff out and replace so it doesn't corrode.
any pump made after 193somthething has sealed bearings.. it's the anti corrosion and pH that gets bad.


Edited by Chris142 (11/07/16 01:37 PM)
_________________________
02 Wrangler durablend 10w40
87 F250 traveler 15w40
04 Tahoe super-s 10w30
Z400 castrol T 10w40
Can am maveric edge 5w40
57 case tractor 15w40

Top
#4243966 - 11/07/16 01:45 PM Re: Why does radiator coolant need to be replaced? [Re: bubbatime]
Pop_Rivit Offline


Registered: 02/09/08
Posts: 6367
Loc: Midwest
Originally Posted By: bubbatime
It lubricates the bearings in the water pump. Those "lubricants" wear out over time.


You shouldn't repeat everything you hear at Jiffy Lube.

Top
#4243977 - 11/07/16 02:04 PM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
KrisZ Offline


Registered: 12/23/06
Posts: 7467
Loc: Toronto, Canada
Water pump or bearing lubrication is nonsense and it has been nonsense for a long, long time in automotive world.

As any automotive fluid, coolant oxidizes, depletes its additives, changes its optimal PH level and simply put, deteriorates through chemical and electrolytic reactions.
_________________________
2015 Dodge Grand Caravan-21k miles.
2006 Mazda 3-155k miles

Top
#4243978 - 11/07/16 02:04 PM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
Kawiguy454 Offline


Registered: 06/01/15
Posts: 579
Loc: Arizona
...Any lubricating needed is just the seal itself. Water pumps have mechanical seal and the water keeps them cool. Anyone that thinks water ever lubricates bearings should think twice

Top
#4244262 - 11/07/16 10:37 PM Re: Why does radiator coolant need to be replaced? [Re: Kawiguy454]
PeterPolyol Offline


Registered: 03/06/16
Posts: 1345
Loc: toronto
Originally Posted By: Kawiguy454
...Any lubricating needed is just the seal itself. Water pumps have mechanical seal and the water keeps them cool. Anyone that thinks water ever lubricates bearings should think twice

Definitely. It's just the seal, which is why I don't like to spin pumps dry, even briefly. The seals are spring loaded too, so it's not hard to imagine how being dry or bathed in precipitated-silicate and insoluble-contaminated coolant can wear out a rubber seal that's spring loaded against a housing. The glycol does indeed provide some lubrication to the seal, but conversely the glycol itself never "wears out".

Top
#4244306 - 11/08/16 02:13 AM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
SirTanon Offline


Registered: 06/23/14
Posts: 2157
Loc: Phoenix, Arizona - USA
Instead of second guessing the recommendation to drain and fill your coolant, ask yourself this:

Is it worth the extra (approximately) $20 I would spend on the coolant (and pennies for the water) to safeguard my engine from potential failure or damage resulting from NOT changing out the coolant at the recommended interval?


In my mind, spending $20 or so for the coolant and an hour or two to drain and fill in my driveway - ONCE per 60,000 miles - is WELL worth it.
_________________________
2010 Ford Fusion SE - 2.5 liter/6F35 Trans - 257,000mi
2014 Nissan Altima SL - 2.5 liter/CVT - 55,000mi

Top
#4244483 - 11/08/16 09:41 AM Re: Why does radiator coolant need to be replaced? [Re: veryHeavy]
veryHeavy Offline


Registered: 11/04/16
Posts: 479
Loc: MN, CA
I recently topped-off the radiator with fresh coolant. Hopefully that will hold me until my 70,000 mile oil change. The dealer charges $150 for radiator flush.

Top
Page 1 of 3 1 2 3 >