Coolant

JTR · Post by **JTR** » Mon Jun 18, 2007 2:35 pm

Hi,

I've just returned from a fantastic trip in our Bongo to the Outer Hebrides. The trip was not without the odd hiccup however! We cruised up to Skye without any problems at all. Toured around the island for a couple of days and then were heading to the ferry when we started to overheat terribly. I stopped straight away and popped the bonnet to find that the water was boiling out through the expansion tank. Having let the van cool down for a good thirty mins, we topped up with water to the right level and set off again only to have the same happen to us again 5 mins later. At this point we called GreenFlag (thank god we had mobile reception!) We were put on a wagon and taken to the nearest garage were they looked at it and said that a couple of belts had slipped off - the 2 attached to the alternator - this was causing the van to overheat - at least it wasnt the head gasget! The parts came in the next day and we were thankfully sent on our way.
However, the coolant has only been filled with water. I now need to replace half of this with the correct anti-freeze. Can I allow excatly half of the water to drain out and then replace with anti-freeze? - or do I need to drain the whole lot and start again?
Any help/advise related to coolant and the replacing off greatly appreciated!
Thanks,
John

Peg leg Pete · Post by **Peg leg Pete** » Mon Jun 18, 2007 2:38 pm

Hi, I would be tempted to drain and refill, you will need to bleed the system

haydn callow · Post by **haydn callow** » Mon Jun 18, 2007 2:48 pm

I would test the strength of the coolant. Drain about a pint by releasing the Radiator cap. Top up the expansion tank to the full with neat antifreeze. Run the Bongo fof a couple of days then test again till you get the reading you want. You can get a cheap tester in Halfords ao ask in any garage. They will do it for you,

mikeonb4c · Post by **mikeonb4c** » Mon Jun 18, 2007 3:21 pm

Question - would the coolant loss detectr have been triggered by JTRs problem before seroius damage was done?

haydn callow · Post by **haydn callow** » Mon Jun 18, 2007 3:27 pm

If the level in the tank had dropped below the probe. YES

JTR · Post by **JTR** » Mon Jun 18, 2007 4:54 pm

Thanks for the replies!

Haydn - were is the radiator cap located? A picture would be great!

Also - is there any particular type of anti-freeze I should be using?

And the anti-freeze tester kit - are they pretty cheep and would I be able to get one from Halfords?

Thakns,
JTR

haydn callow · Post by **haydn callow** » Mon Jun 18, 2007 4:59 pm

Get one from Halfords.
The cap is :- open the bonnet...remove the large plastic air intake (2xclips) It's there in front of you.
Glycol blue antifreeze from halfords.

JTR · Post by **JTR** » Mon Jun 18, 2007 6:46 pm

Thanks Haydn,

I've taken the air duct off and I can see a cap on top of the radiator - how do I let the water out of the system from this? Do I have to syphon it out?

Cheers.,
JTR

waycar8 · Post by **waycar8** » Mon Jun 18, 2007 6:51 pm

JTR wrote:Thanks Haydn,

I've taken the air duct off and I can see a cap on top of the radiator - how do I let the water out of the system from this? Do I have to syphon it out?

Cheers.,
JTR

take the cap off the rad thenrelease the expansion bottle cap

Vanmanerik · Post by **Vanmanerik** » Mon Jun 18, 2007 8:37 pm

Ermmmmmm.
Drain about a pint out of the expansion tank and then fill it up full and run it for a day??????

Where is the expanded water/antifreeze going to go when the engine warms up? Out of the tank................ is antifreeze that cheap?

Why is there a max and min mark on the expansion tank, if you fill it to the min level then usually when the engine is warm it will rise to the max mark, leaving some room in the expansion tank.

There would be no harm in draining 5 litres of coolant off and replacing it with 5 litres of antifreeze. You will end up with a stronger solution anyway doing it this way so no need to buy a strength tester.

Its no big deal bleeding the system if your cooling system is free from obstructions, the radiator is clear and the thermostat is working correctly and your coolant pipes are not leaking, if you are worried then flush the system, check that the radiator is not blocked, check the thermostat, check your coolant pipes, if all OK then refill with 50/50 water antifreeze and all will be well.

JTR · Post by **JTR** » Mon Jun 18, 2007 9:08 pm

Right - I'm still a little confused as to how you actually let some water out of the system! If I undo the cap on top of the radiator and then undo the one on the top of the expansion tank - then water will flow out of the top of the radiator? I then replace the water lost with antifreeze into the expansion tank?

Cheers,
JTR

Vanmanerik · Post by **Vanmanerik** » Mon Jun 18, 2007 9:32 pm

As you face the van from the front there is a drain tap on the left hand lower side of the radiator.

Or if you want a fast uncontrolled drain then remove the lower coolant pipe from the radiator.

JTR · Post by **JTR** » Mon Jun 18, 2007 9:41 pm

If anybody can post a picture of the radiator tap then I would really appreciate it! I cant see it anywhere! Do you access it through the bonnet or from underneath the front of the van?

waycar8 · Post by **waycar8** » Mon Jun 18, 2007 9:43 pm

JTR wrote:Right - I'm still a little confused as to how you actually let some water out of the system! If I undo the cap on top of the radiator and then undo the one on the top of the expansion tank - then water will flow out of the top of the radiator? I then replace the water lost with antifreeze into the expansion tank?

Cheers,
JTR

basically yes.

but like vanmaneric says, if you are going to change the coolant totally (if you think/capable of doing it this way) just unclip the bottom hose of the radiator and let it run out, but if you just want to top it up, empty the expasion tank as said, replace cap on radiator then fill the expansion tank up with neat antifreeze.

btw, how much water did you fill your bongo back up with?

Peg leg Pete · Post by **Peg leg Pete** » Mon Jun 18, 2007 9:43 pm

under van, look through driver side wheel arch

Coolant

Coolant

Top up with coolant

Drain coolant.