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Discussion Starter #1
I've just had a coolant hose burst on me. Not a big deal... new hose £33 fitted in 20 mins, and it may have sorted a leak that i've had for some considerable time but have been unable to find because it's leaking so slowy.

Anyway, i've topped it up with plain water for now because i don't want to fill it with coolant only to find that it's still leaking badly and have to drain it and buy more coolant. I have the coolant and WILL add it to the system on Monday once i'm happy there's no leaks.

However, i noticed on my way to work tonight that the engine didn't get up to temerature again, this time it was waay lower than usual (70 degrees) and that when i stop the car for any more than about half a minute or so the blowers would start to blow cold air, even when set to hot. As soon as i drive away they go hot again.

I realise that lack of coolant in the system could possibly stop the engine getting up to temp, but can't understand how it would have this effect on the heaters.

Any ideas folks???

Cheers,

Gordon.
 

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Hi Gordon coolant problem

Hi Gordon, I have read many of your threada and you are more than capable mate of sorting this.

I can see perhaps 2 -3 problems.

1) is the engine / rad still leaking water? (puddle in the morning beneath the engine bay)

you may still have a minor leak, introducing air into the system and coolant is low thus not reaching full temp.

2) water pump- have you checked for leaks, noise, wear?

3)thermostat not working fully.


Check your coolant levels in the morning for consistency and you will see if it is a sealed system.

If not, I would re-flush the cooling system, perhaps jet pipe, then refill making sure that there is no leak then add the coolant.

Go for a long drive, let it cool down then check the coolant level/ top up to get rip of any air.

Also when filling have the heater on and in full / hot position.

I have noticed a puddle under mine this morning. When I start she starts dripping in a consistent flow under ther left hand side of the bumper. I do not know what it is yet, but Im stripping her down today (its cold outside but better than having a blown gasket).

I suspect a leaky hose and I did top it up to the brim two days ago???

hope this sheds some light on problem Gordon.
 

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1999 108CDI
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If you have a 638, the maximum fill level for coolant is to the ledge in reservoir, approx 4" below cap, with "max" stamped on it. Not sure if 639s are the same, but if you fill it to the brim on a 638, you may over-pressurise cooling system and cause a leak. Reservoir space above "max" mark is for expansion.
 

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v220 ambiente
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Hi
Did the engine overheat when you had the original problem? It does not take long, if the coolant level drops below the cylinder head level, to overheat the head and then gasket failure. Your symptoms are identical to those I have had in a number of cars (Dolomite, Imp, Astra diesel, Mini etc) where cyl head gasket has failed. Combustion gases can get into the coolant leading to airlocks. If this has happened the system will probably get over pressurised and gas/steam/coolant will blow out through the vent pipe.
Best of luck
G
 

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03 vito 110 cdi van
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Hi you can buy a kit to test the coolant to check for co2 on e-bay, better than guessing. It is a liquid that changes colour.
 

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Discussion Starter #7
Thanx for the replies guys.

G,

When i had my original problem the car didn't overheat as such, the temp guage did go higher than it usually does (about 90degrees instead of 80) but i suspect that it wasn't reading accurately at all since there was no water in the system due to the leak, and worryingly the engine temp may have been a lot higher than the guage was actually reading.
 

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Discussion Starter #8
Guys,

Once again i'm having trouble trying to get the cooling system operating properly.

Last time i changed the hose and it took me a while to get it topped up and working properly and when it eventually did, it worked fine. but i was using fresh water only because i didn't want to leak coolant if the system wasn't fixed properly.

So i drained some water and added coolant, but it seems to be giving me trouble again... it just won't get above 60 degrees now unless i'm on the motorway and the heaters are ok, but not as good as they should be, and they go colder when i stop at lights etc.

Also, i topped it up to the ledge, but after a bit of running the water level has actually gone UP... it also seems like there's no pressure in the system after it's been switched off for a while (pressure used to remain in the system for days) thought there was pressure in it when i opened it straight after switching off.

Sorry for rambling on, but i really need to get this sorted with this cold snap that we're having.

Any help would be very much appreciated.

Thanks,

Gordon
 

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Also W639 can't over-pressurize as there are vent holes on the front of the external reservoir, just above the big and small hoses, covered by a little vertical clip.

BTW, today gave the reservoir a good flush and found a square filter inside. Looks like this (the bottle is dishwashing liquid):



I guess it's there to soak up gunk, of which there was some. Greasy white. None in the radiator, though, just in the expansion reservoir.

Which brings me to my question: there was only water in the cooling system, which has no anti-corrosive additives (fine otherwise as there's no freezing here) - any specific type of coolant I should use?
 

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2001 110 CDI (sold) 2006 111 CDI Comfort (current)
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Does anyone know if the Vito has an EGR Thermostat? I'm pretty sure it does. Would this be by-passing the main thermostat and sending the coolant into the radiator and thus causing the 60 degree running temperature?
 

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v220 ambiente
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Hi Gordon
Definitely looks like head gasket.
Level goes up because gas bubbles are leaking into coolant via the failed gasket. Often the leak is so bad and the pressure high enough so that coolant gets forced out through the filler cap. When engine stopped the coolant pressure will cause coolant to bleed back into the cylinders.
All the best
G
 

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Discussion Starter #12
Would a head gasket not make the oil go all that emulsified way though (which it's not, it's quite healthy looking). I'm kinda thinking that you're right though, i just don't want to admit it to myself :crybaby2:

How difficult would a head gasket be for a DIYer???

Cheers folks,

Gordon
 

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v220 ambiente
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Hi Gordon
It all depends where the gasket is leaking and so where the coolant is going. If it is only a small blow by between cylinder and a coolant space the biggest effect will be gases from combustion getting into coolant, and possibly when the engine is off some coolant getting back into the cylinder, but pressures involved are vastly different. As gases keep blowing through the gasket will get further erroded and the problem gets greater.
I think you can get the coolant tested, the combustion gases make it more acid. I presume diesels, like petrols, can also have a compression test done but I guess that involves removing an injector.
I have changed many a gasket on ohv petrol cars, quite easily and quickly but I would hesitate a lot before tackling a modern diesel. It is vital to tighten bolts exactly and check flatness of head and block. Also probs with chain to the ohc and setting timing etc. Ugh!
G
 

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Discussion Starter #14
Yeah i've done head gaskets on my old fords on a few occasions, but this car is completely different and i don't really fancy it.

On a slightly more positive note, i removed a bit of coolant last night since it was over the max mark when cold, and this morning when i drove the car, the temp went up to about 75-78 degrees where it usually does and it stayed there. I know everybody says it should hit about 82 degrees, but i don't think mine ever did get to that temp.

I'll need to go out later when it's cooled down and check to see if there's any pressure in the system.

I've definately still got the head gasket at the back of my mind though.
 

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I have exactly same problem. My heater blow cold and hot. Motor temp is normally 60 degrees then it jumps to 80 degrees and blow cold air. After about 3-5mins temp goes back to 60 and blower blows again hot, that continues all time. There was hard pressure in radiator after night, but now there is not so bad pressure in radiator, maybe still too much..

If i fill radiator, full there comes bubbles and level is going up and down. But it not eat coolant or overheat up and motor temp is maximum in 80 degrees.

My biggest problem is now that it takes so long time to get hot air in cabin.

(i have thinked head gasket failure too..)

My vito is 110cdi year 2002.

ps. where is the water valve?
 

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Vito 108D 1997
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Hi Gordon, I have read many of your threada and you are more than capable mate of sorting this.

I can see perhaps 2 -3 problems.

1) is the engine / rad still leaking water? (puddle in the morning beneath the engine bay)

you may still have a minor leak, introducing air into the system and coolant is low thus not reaching full temp.

2) water pump- have you checked for leaks, noise, wear?

3)thermostat not working fully.


Check your coolant levels in the morning for consistency and you will see if it is a sealed system.

If not, I would re-flush the cooling system, perhaps jet pipe, then refill making sure that there is no leak then add the coolant.

Go for a long drive, let it cool down then check the coolant level/ top up to get rip of any air.

Also when filling have the heater on and in full / hot position.

I have noticed a puddle under mine this morning. When I start she starts dripping in a consistent flow under ther left hand side of the bumper. I do not know what it is yet, but Im stripping her down today (its cold outside but better than having a blown gasket).

I suspect a leaky hose and I did top it up to the brim two days ago???

hope this sheds some light on problem Gordon.
Did you ever find what this problem was, as mine is doing the exact same (108D) Please help !!
 
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