MK2 8v Digifant Coolant Problem

[Mars Attacks]

Hi, I have a problem with my MK2 and i'm fearing the worse at the moment.

Basically, a few days ago, the coolant level warning light came on. I stopped the car and saw that the level had dropped quite low in the expansion tank so i topped it up. didn't think much of it.

then the next day, i started up the car and the level light flashed up straight away, i checked the bottle and the water had dropped down again! this happened again over the next few days.

Tonight we looked at the engine to try and figure out whats wrong. it looked like the water isn't circulating through the coolant system as it wasn't returning through the top pipe back into the expansion tank. It that when you take the expansion cap off after running it for a short while, it builds up a lot of pressure and then shoots all of its load out.  Plus, there appeared to be more white smoke coming from the exhaust as usual, but that may have been the cold weather.

There are no obvious signs of a leak anywhere on the car and the only things we can think of are blockage in the system, knackered oil cooler / water pump or the dreaded head gasket.

The car still runs ok and the oil and water temps stay well within good levels, but obviously i'm not going to drive it till i can think of what is wrong.

Any ideas anyone

[...joe]

take the oil filler cap off and have a look for mayonaise type gunk around the cap. if your getting white smoke this would imply it was the head gasket. if you have the gnuk as well it is almost definately a head gasket! sorry dude, but you can drive a 8 valve fine with out realising the head gasket has gone. if your that bothered take it to a garage and they can put a tester in the coolant to tell if its been contaminated. that way you'll know for sure, but i'd say it is a head gasket.....

[free]

water pump? is there any 'mayo' under the oil filler cap? or on the dip stick that will prob b the head gasket

[Mars Attacks]

there is no mayo under the oil cap at all and the dipstick looks as normal.

we filled the coolant back up last night (4 litres of warm water put in) then i drove home (2 miles maximum) and left the car overnight

opened her up this morning and the expansion tank was totally empty! but there were no signs of it leaking out. its very strange. i fired it up and it started and ran fine, but again, no coolant was being returned to the expansion tank. its getting very wierd.

as you'd expect, i've taken a different car to work today!

[richandhazel]

I'm afraid that does sound like your head gasket. Probably gone between one of your bores and a water way. Oil way not effected.........yet

At the end of the day if the water ain't coming out anywhere obvious and you're losing it at that rate it's got to be going out the exhaust :'(

A leak down test would probably diagnose it for certain.

[Mars Attacks]

i was fearing that, any idea on the potential cost. once its done is it normally plain sailing from there?

[Gambit]

you can buy a compression tester for about ?15 from Halfrauds or any good motor factors

compression test is the only concrete way you'll know if the head gasket has gone

also, just on the white smoke. you'll know the difference between normal exhaut condensation and proper white smoke. white smoke stinks!! and when you plant the throttle it will blow big plooms of white smoke!!

can u not fill it with water then sit with the car idling and check to see if there is any water leaks?

[Mars Attacks]

yes, i'll have a go at doing that tomorrow, its strange as nothing was being returned to the expansion tank when the car was idling almost as if there was a blockage, but for it to dissapear so quickly is weird.  Surely even if the headgasket was leaking, some water would circulate through the system back the expansion tank?

[richandhazel]

Sounds like the thermostat isn't getting a chance to open to allow it to recirculate

[Mars Attacks]

bottom hose felt as warm as the top when it was warmed up so i'm not sure it will be that but i'm no expert.

well ive got a lot of things to check then tomorrow. i'm just praying that i've missed a leak or something like a water pump is knackered. but i won't hold my breath.