Tintop Cooling Fluid Problem

[Guest paulh]

Hi guys,

 

I have a little niggling problem. I have a VW Golf 1.9 TDI with the 115BHP (AJM) engine. I believe this engine was used in the VW Sharan and Seat Alhambra aswell as the Golf estates.

 

The problem i have is that since October (ish) last year, the cooling system seems to empty itself rather quickly. It drinks about 2 litres (after it's been dilluted) every month or so. I have left the car on the hard standing driveway and completely covered the underside of engine bay with cardboard, and i didnt notice a single drop that had leaked. The only thing i can think is it leaks when engine is running (although i did try leaving the car standing after a long run, and still no leak).

 

Just wondering if this is just normal for the winter weather, or if i'm using the wrong coolant (i am using a red coloured one if that helps). Somebody recommended buying some RadSeal? anybody used this stuff/ got any opinions on it?

 

Hope i've put down all info req'd!!

[Guest paul091085]

Totally different car, but i had a similar problem with a ford orion that i had. Started losing water and gradually got worse, but with nothing drippping when the car was switched off and standing still. Turned out to be the water pump o-ring. might be worth checking....

[Guest Eric]

just a thought, the oil level isn't high by any chance

 

it's gotta go somewhere

 

ek

[Guest paulh]

Strangely enough my oil warning light came on this morning!! I assumed the oil was low, rather than high! I left the car at home and used the missus's! I'll have a look when i get home. Although i did check the oil about two weeks ago and it was all normal, but had the cooling problem since October!

 

Thanks paul, i'll get that checked out! I am no mechanic i'm afraid, so will have to ask the garage to look at it i guess, just moved to a new area, so wanted some idea of the problem before i go to get ripped off by a garage!!

[Longboarder]

Find an old rad cap, drill out the central rivet to remove the pressure plate and springs. Enlarge the hole and fit a tyre valve. May need some goo/rubber gasket to get it sealed. Attach foot pump and you can now pressure test the cooling system. No more than 20psi max and you see an external leak if there is one. If no visible leak but the pressure and water level in the rad drop then suspect the cylinder head gasket is gone allowing water into a cylinder or the sump. Turn the engine over two full revolutions with a spanner on the crankshaft pulley nut to check for hydraulicing before starting it and plan on a skim and a head gasket change.

 

Nigel

[Guest Petemate]

Sound advice Nigel - you beat me to it (guess who is having a quiet last hour of shift at work!!)

Pete

[Guest paulh]

Cheers for the advice Nigel. I checked the oil last night, and it's seemed normal. Seems like the vDub puts the oil warning light on when the oil has quite a bit left in it! I topped up the oil (looked normal, in colour and consistancy) and the warning light went away! I take it the oil on the dipstick would be thinner and a different colour if the coolant had made it into the sump?

 

I'll have a go at your hoodies style system test at the weekend! I have to say it's a genius little work around. Just out of interest, if there is not an obvious leak, how do i tell if the pressure/ water level drops in the radiator?

 

Also, how difficult/ expensive is it to chnage the head gasket (ie, would it be a good idea just to change it anyway?

 

Paul

[Guest peter2b2002]

before taking the head off, try doing a pressure test on each cylinder or if you can find it , there is a test you can do on the rad water which tells you if there is combustion gasses in the water, if so it's your head gasket. had that on my old s2 land rover that i got cheep at a sale, ran fine on it's own but gut less when towing which is why it was being sold, it did loose some water not a lot, checked the compressions on the cylinders No's 2 and 3 low, new head gasket - pulled like a train

pete2b

[Longboarder]

Paul, if you get a good seal with the cap and the tyre valve then pressure should stay constant. Make sure you have a sealed system or seal any overflow pipes. Top up the rad or header tank, depending which you have.

Most cheap footpumps have a pressure gauge on them. You will only be pumping a small volume of air, maybe only one or two actuations of the pump to reach 20psi. The pressure should hold there if all is well. If there is a leak the pressure will slowly drop and water must be going somewhere. It must be dripping out of a hole in the system somewhere, rad, pipes, joints, pump and heater or if you are unlucky in the engine. Take your time. If the pressure drops and you can't see a leak keep pumping it back up for ten minutes or so till enough has leaked externaly to find it.

If it's definately dry externaly after 10 mins, gently let the pressure out and remove the cap to check the water level in the rad/header tank. Has it gone down? If yes then water has to be going somewhere and if its definately dry outside then it must be somewhere in the engine and you are looking for evidence of leaking head gasket or possibly even a cracked head or block although this would be rare on a cast iron diesel.

 

Nigel

[Guest Guy]

I had a similar problem a little while ago on my Corsa, it was using coolant slowly but not leaking. It turned out that my heater matrix was leaking, I think it was only coming out under pressure and because it was hot, the water evaporated away. I only found it when it started to get much worse because I noticed the wet carpets and the screen steaming up.

[Guest salty_monk]

I had this one a petrol Astra, was water pump O ring. Couldn't see it unless it was running & then only if you looked very carefully, a drip every 20 secs or so....

 

Heater matrix is a suspect as is the rad core. Try leaving it ticking over on a flat dry surface for half hour & see if you get any puddles that way....

 

Dan

[Guest paulh]

Well done everyone! Did exactly as said, Pumped up system to 20 PSI. This did not seem to show anything. Pumped it up another 4 or 5 psi and all of a sudden i can hear a hissing!! Found it, rusty jubilee clip had been vibrating a while and grazed a hole through a pipe. Replaced rubber pipe, and new jubilee's both ends (other looked dodgy too). I'm hoping this has solved my little problem. Cheers guys.