Coolant Change - to flush or not to flush?

[guest5826]

So I have a 2004 Jazz with an uncertain maintenance record for the last two years.  Up to that time, everything was stamped by the Honda dealer in the book.  I am thinking that the coolant could be overdue a change.  A few times I have smelled a slight sweet smell that makes me think that the heater core may have a small seep.  The level has been holding so if it is leaking, it is only a slight one. 

I am thinking that a flush could make the seep worse and that with an old system maybe it is enough to drain and refill with the Honda premixed coolant?  Or maybe a flush and then some K-seal (or similar) with the new coolant? Has anyone done this?  Opinions welcome. 

The manual indicates that I need to drain the block as well which I have never had to do this on any other car.   

[guest5589]

http://hondakarma.com/guides/maintenance-schedule-for-normal-conditions.80/

The normal service schedule states that the coolant must be replaced at 200,000 km (120,000 miles) or 10 years, then replace every 100,000 km (60,000 miles) or 5 years.

You can use something like this to check the condition of the coolant and decide what you want to do with it
http://www.ebay.co.uk/itm/ANTI-FREEZE-TESTER-ANTIFREEZE-COOLANT-TEST-RADIATOR-PROTECT-YOUR-CAR-VAN-427656-/221980021148?hash=item33af0a519c:g:iTIAAOxyzi9SdQ3O

with regards to the leak, I doubt you can swap the heater core out yourself.. if it aint broke dont fix it.. unless you are loosing coolant.

Simply drain the radiator and fill it with fresh coolant but you have to carefully remove all air from the cooling system and it can be a right pain. best trick i have seen is when the radiator is filled ..remove the top hose from radiator and lift it as high as you can and then pour coolant into it waiting to let the air bubbles come out. .when you are confident there are no more bubbles, you can refit the hose and top up the radiator. remember to keep the reservoir at the right level and check back for level after 20-30miles.

[guest5826]

Thanks for the advice and links.  I am going to pickup a tester tomorrow. 

So do most people stick with the genuine Honda premixed antifreeze?  I saw that Comma claims that their xStream G30 is a suitable replacement. 

[JazzyB]

| would stick with the Honda stuff, its ready mixed and matches the stuff already in there

[culzean]

Just a couple of things,  that tester will only check specific gravity of coolant which will give amount of ethyline glycol in the mix,  which gives the freezing point,  but remember 50% is the optimum dilution and both below and ABOVE that amount of glycol will lower the freezing point.  The glycol (bit that stops it freezing) doesn't wear out over time,  the stuff that wears out is the anti-corrosion buffer chemicals (OAT or HOAT,  organic acid technology or hybrid organic acid technology,  both are long lasting corrosion protection).   I normally use Halfords 50% advanced OAT anti freeze in 5 litre for about £20 - whatever you used make sure it is 'silicate free' and suitable for mixed metal systems.

The components of  antifreeze are colourless, the colour is only added to show up leaks and confers no special properties onto the mix,  one drawback of using another colour is that unless you completely drain the system and refil you can get say orange added to green which gives a yukky colour.

[how2]

Hi Guys

Do I need to flush the coolent out?

2004 Honda jazz se sprot 1.4. I have owned it since new, and have seviced it myself, I'm going to change the coolent after 12 years, yes I know 2 years too late. It's done about under 34000 miles.

Can i just empty the coolent like in the handbookk or should i follow hynes manual and flush the sysytem. If I need to flush it can i use this TRIPLE QX De-Ionised Water 5Ltr?

If I flush it then replace using Honda coolent will the 50/50 ratio go down as there will be water in the system.

What I would like to is follow the hand book.

[culzean]

Don't let de-ionised water near your car (except in the battery) - chemical engineers call it the 'universal solvent' as it will scavenge its lost  Ions (electrically positive charged particles) back from any material (especially metals) that it comes into contact with.  Systems that use DI water are designed with great care,  and cannot contain metals normally found in a car engine (aluminium, copper, steel and brass) - some electronic and electrical cooling systems use DI water because it does not conduct electricity,  but these systems are designed for DI.  Chemists use DI water because they are pretty sure it will not contain unwanted chemicals and upset their experiments.

I would use a premixed 50/50 solution of universal OAT or HOAT (slicate free) Halfords do a 5 litre universal one, I use it in my motorbikes and cars - I just  drain whatever would come out from the normal tap in bottom of radiator (about half the system quantity) and top it up with 50/50 premix, then run the car for a week and do the same (this way you will replace at least 75% of coolant),  keep your eye on the radiator level for a while after both procedures and top up if needed,  I have never bothered draining and refilling the expansion bottle (you either need to remove the battery or go under the car to remover the bottle).  If you want you can suck out the fluid from bottle with a siphon thing (available from home-brew shops) and refill to halfway between max and min level.

Remember the ethylene glycol anti-freeze bit does not lose effectiveness over time,  all you are doing is making sure the corrosion inhibitors (which do get used up) are being replenished.   

Its a pity that the Jazz doesn't have a proper temperature gauge because the first sign that you have an airlock in the cooling system is the temperature gauge goes a lot higher than normal.

if your heater does not work very well after the coolant change you will probably have an airlock in the heater circuit. Try to do the drain and refill with front of car higher than the rear (if you put front wheels up on ramps it also enables you to get access to coolant expansion bottle from under the car) as this allows air to come out easier.

[guest1372]

I did mine a while back, according to hondafitjazz.com guide.  Full capacity is just under 4 litres depending on A/C, manual/CVT and what is in the expansion bottle.  As described above a rolling change to freshen up the contents is probably the pragmatic approach to take and the easiest / least problematic.  There are two drain plugs, the bottom radiator one plus one in the engine block (just above the oil filter), but draining the block might lead to air locks and subsequent gurgles for a while.  If you briefly run the car and leave the cabin temp on hot before you start, then it will help it drain from the heater core as well.

The Triple QX Red premix is just fine, so no worries about the water contents or mixture and it works out a bit cheaper.
--
TG  (Also still owning my original Jazz - just no need to change it plus cash in the bank.)

[how2]

Thank TG and Culzean

I have already bought the Honda 5 lt stuff for£20, I know it's twice the price but better safe than sorry.

The manual does say leave the it on Hot but should I also press the A/C button as well?

I will not be doing a flush but will slowing pour the coolant and rock the car side to side and up and down. I will also get a wooden spoon and tap all the hoses and squeeze them as well. I have one of those steam cleaners when pour in the water rocking it and turning it on it's wheels help get the air out.

I have never checked the coolant level or oil level, only when I do an oil change do I fill it up with 3.6lt of oil. I hope the coolant is at the top of the neck.

[guest1372]

The Honda stuff is best peace of mind and still cheap enough.  A/C selection won't make a difference but the heater core does take the engine coolant through it.

If you can see some coolant in the expansion bottle then there should be enough in the system in normal use - shining a torch at it while rocking the car helps to see the level.  When filling after a drain then it's just up to the neck of the rad plus a squeeze of the various hoses, run the heater etc.
--
TG