Golf Drinks Water

Hello, new to this and need a bit of advice please. I have just bought a Clipper (she's nice). Got 127k on the clock, cambelts done, serviced etc however, she is drinking a lot of water (about 4 ltrs in the last 4 weeks). Had it out today but temp shot right up whilst waiting in traffic and had to stick 2 kettles of water in. I have let the engine tick over and it seems fine now but i am sure it will go again. What ya reckon? Thanks

Leak somewhere in the cooling system. If its not leaking and its consuming water then bad news - likely be HGF! If you've let it run down then topped it up, probably developed an airlock. Overheating could be due to low/no coolant or airlock, and could have blown the head gasket if not already gone.

Thanks Paul

Thats a bit depressing. Since i have put the water in i have run it idle and it's not overheating. Fan and everything is coming on when the gauge gets to the mid point so it appears OK. No smoke from exhaust!!! I don't know maybe a trip to the garage or i will get my hands dirty (although knowing me that will end up as a full rebuild of the car, kind of like a Pringle)
Thanks for the quick response.

Mark

An airlock could reveal itself in 30 or 100 miles, did you turn the heater to maximum during filling the cooling system up?

what colour is the water in the water tank? and does it look clean or is there a light oil on the surface (looksa little like a rainbow in the surface)?

paul_c said

An airlock could reveal itself in 30 or 100 miles, did you turn the heater to maximum during filling the cooling system up?

Hi Paul, No I ran the engine after i filled it!! Should i have done?

whatalotafun said

what colour is the water in the water tank? and does it look clean or is there a light oil on the surface (looksa little like a rainbow in the surface)?

Hello

Water is a kind of light brown colour. I checked it on the return from the radiator. Guess this is some rust in the pipes/Rad ?

semtex73 said

paul_c said

An airlock could reveal itself in 30 or 100 miles, did you turn the heater to maximum during filling the cooling system up?

Hi Paul, No I ran the engine after i filled it!! Should i have done?

Doesn't make sense - of course you should run the engine after filling it. Did you run the engine and have the heater on DURING filling it though?

Have a good look around all the pipes and rad checking for sign of leaking. Besides being wet/damp you need to look for any signs of white staining, which will be escaping coolent that has dried.

Also on the rad try removing the top brakets that hold it in place, these sit in little plastic pockets on the rad. Can collect water here and rust/expand over time, breaking the rad. Are footwells dry?

Given the amount your loosing must be a fairly obvious leak or gasket.

Also if the water is mucky you really need to change for the right vw coolent (G12 from memory) mixture asap. It may be they had stuck some rad weld in previously and likely to be brown also if it being toped up with just water as coolent will have all gone.

when I got myn I had to catch up with, new fuel filler neck, new rad and collent flush/change and new topmounts and dampers. So catching up on some maint is expected on older cars. All straight forward jobs with these cars, a bit like mecano just with bigger rusty bolts.

the first thing you should do when diagnosting coolant system faults is replace the header tank cap with a new blue one. the older caps had a fault where they would not release pressure at the correct time.

Obviously before you go out shopping check engine over carefully for leaks, the flanges on the front/side of the head are common leaky spots, but I wouldnt expect it to cause these symptoms if only a small leak, sounds more like its got a big leak or its boiling over, then as coolant drops temp sensor runs dry and quickly heats up from engine heat thru the flange.

check the waterpump and thermostat next. Take the header tank cap off, and run engine from cold.  Rev the engine and you should see a strong spary of coolanty out the top thin hose to the header tank, if not the waterpump is bust, or the radfiator or the thin hose to the top of the tank is blocked.  Switch engine off and blow down the pipe to clear any blockages and try again.
Next feel the lower rad hose it should stay stone cold till the gauge gets to about half, then it should heat up. if it stays cold the whole time then the stat is stuck shut, and if gets warm very quickly then it is missing or stuck open.

Also check the fan, it should cut in when gauge gets to about 3/4. If it doesnt feel the rad on passenger side where the sensor for it is, if its cool then rad is partially blocked or waterpump is buggered.  If its hot then fan or the switch is broke.
Switch engine off then unplug the fan sensor switch, bridge the red wire to the other wire fan should run. if it has a 3 pin plug you have dual speed fan, bridge red wire to each of the other wires in turn and it should run slow and fast.  If it does this then the switch is at fault.
If it doesnt, run 2 wires to fan direct from battery, if it doesnt run fan is toast,m if it does the wiring or fuse is the problem.

rubjonny said

the first thing you should do when diagnosting coolant system faults is replace the header tank cap with a new blue one. the older caps had a fault where they would not release pressure at the correct time.

Obviously before you go out shopping check engine over carefully for leaks, the flanges on the front/side of the head are common leaky spots, but I wouldnt expect it to cause these symptoms if only a small leak, sounds more like its got a big leak or its boiling over, then as coolant drops temp sensor runs dry and quickly heats up from engine heat thru the flange.

check the waterpump and thermostat next. Take the header tank cap off, and run engine from cold.  Rev the engine and you should see a strong spary of coolanty out the top thin hose to the header tank, if not the waterpump is bust, or the radfiator or the thin hose to the top of the tank is blocked.  Switch engine off and blow down the pipe to clear any blockages and try again.
Next feel the lower rad hose it should stay stone cold till the gauge gets to about half, then it should heat up. if it stays cold the whole time then the stat is stuck shut, and if gets warm very quickly then it is missing or stuck open.

Also check the fan, it should cut in when gauge gets to about 3/4. If it doesnt feel the rad on passenger side where the sensor for it is, if its cool then rad is partially blocked or waterpump is buggered.  If its hot then fan or the switch is broke.
Switch engine off then unplug the fan sensor switch, bridge the red wire to the other wire fan should run. if it has a 3 pin plug you have dual speed fan, bridge red wire to each of the other wires in turn and it should run slow and fast.  If it does this then the switch is at fault.
If it doesnt, run 2 wires to fan direct from battery, if it doesnt run fan is toast,m if it does the wiring or fuse is the problem.

Thanks for this! Right update, have been running the car as normal for the last 2 weeks and it seems ok however, i checked the expansion chamber today and there was no water in it. I left the cap off, turned on the heater and topped it up (took about 1 ltr water).

I continued to let it run and now that i have read through hundreds of threads on here (excellent site!!!!) i can now eliminate the following:

Water pump is fine (i can see it pumping on the return).
Pipe between water pump and lower rad is cooler than above.
No sign of mayo on oil filler cap.
No indication of water leaks on pipes or fittings.
Fan works fine and comes on when gauge gets just over half way.

On another note, i did notice that when she gets hot a rattle starts to appear. Although quite difficult to accurately locate it does appear to be coming from the belt area (water pump, alternator). Do you think these are connected.

It's doing my head in and now i have developed a leak between the engine and gearbox. Maybe i will put it in my garage and just replace the whole lot. Anybody know what i could replace it with (something a bit more responsive would be nice).

Thanks everybody, really appreciate your responses.

Mark