I THINK MY HEADS GONE!!!!

[Walesy 0]

hi..im having nightmares with my 8v raddo all of a sudden! after 18k of trouble free motoring! . first it was running REALLY cold, as in the temp needle would rise when i was idoling but fall back down to the pin when i started driving...so i changed the temp sender switch and that sorted it out,

 

whilst changing the switch i lost a bit of coolant so i put a tad in and off we went. the next day (while a friend was driving it!) the temp went right up and the light started flashing, we put a bit more water in it and it was fine again.

 

a few days later (after driving perfectly for miles!) the temp started rising horribly (oil temp as well) and the light started flashing again. I have noticed that the fan wasnt coming on untill the car was VERY hot and wouldnt stay on for long...so i thought it could be a fan temp sender...so i changed that...and the fan still isnt coming on when it should...

 

it seemed like it was an airlock because ive noticed i bubbling noise when i turn the engine off...ive tried to rid the car of the airlock but this doesnt seem to have an effect...the big hose that goes into the engine seems really hot, yet the water in the header tank doesnt? ...im just confused now!!!! andd i'm coming to the conclusion that im going to have to have the head gasket changed :( ..can anyone think of anything else worth trying first??? cheers guys!

[Walesy 0]

no-one?

[G60Dan 0]

Might be worth changing the thermostat before you whip the head off

[Reggit 0]

I'd say thermostat stuck closed.

[Walesy 0]

brilll...thanks gents..ill try that first

[Rossco 0]

Yeh if the thermostat is stuck closed then it wont allow water to go through the radiator and the thermo-switch for the fan is in the radiator so that would explain why the fan isnt coming on, best check the stat matey, not expensive and about 30 mins work on an 8v

[Walesy 0]

great...i was gonna change the thermo when it was running cold but the temp sender switch sorted that so i didnt end up doing the thermo...ill change it over the next couple of days and ill post what happens...thanks for the input..its gratefully recieved!

[CoxyLaad 0]

definately the thermostat - the fan isnt coming on because the water in the rad is still cool, if the stat is stuck closed it will be only allowing a tiny amount of water to pass. had this on a vr, exact same symptoms

[VEEDUBBED 0]

Remember to drill 2 small

(3/4mm) holes on the thermostats

outer flange otherwise bleeding all

the air out can be a pig to carry out,

On my old golf 2 16v this was the only

way to get all the air out.

[Skimask 0]

Remember to drill 2 small

(3/4mm) holes on the thermostats

outer flange otherwise bleeding all

the air out can be a pig to carry out,

On my old golf 2 16v this was the only

way to get all the air out.

 

Yep, i've noticed on some newer thermostats there is no 'weep hole' which would allow water (and air) to pass if the thermostat is stuck shut!

[Walesy 0]

whys that then??? if it needs one why isn't there one on there????

[Skimask 0]

whys that then??? if it needs one why isn't there one on there????

 

I think its because the manufacturers want the car to get up to temperature quicker. If the thermostat lets water pass through when cool - it'll take longer to reach operating temp.

[G60Dan 0]

If you put a hole in it, and then a few years down the line it goes again, would it not be harder to spot whether it was gone or not - resulting in the car not running right, but not having the symptoms of a knackered thermostat??

[Baz2004 0]

You could also replace expansion cap, Ive heard the rubber seal can go on these breaking the airlock causing water to leak out the overflow. Its more than likely your stat but it would be worth while taking off the water pump also to make sure its in order. Also while you have that off check for any blockages in the pipes leading to and from the rad + pump keep an eye for oily coolant cus that's a sure sign that you may need the head done..

[Henny 0]

DO NOT drill holes in your thermostat. This is a BAD bodge and will mean that your engine takes longer to get upto temperature and therefore will incur more wear!

 

corradowales, I concur with the peeps above that this is probably a stuck thermostat problem... 8)

[Walesy 0]

unfortunatly i have changed the thermostat (withouth the recomended holes!) and it hasn't sorted it :( ....the car is having a new head gasket as we speak( or type).....i'm paranoid now that its gonna be the expansion cap though! :roll:

[Walesy 0]

thanks VERY much for everyones help again though....cant fault you gents!

[Baz2004 0]

unfortunatly i have changed the thermostat (withouth the recomended holes!) and it hasn't sorted it :( ....the car is having a new head gasket as we speak( or type).....i'm paranoid now that its gonna be the expansion cap though! :roll:

 

 

Was she oily? Look on the bright side she's good for another 100k with the head done provided you look after it. Head work is never money wasted the car will drive better/smoother and be more economical, be sure and get a new expansion cap all the same last thing you want is to cook the new gasket!

[Walesy 0]

be sure and get a new expansion cap all the same last thing you want is to cook the new gasket!

true true...cheers!

[Walesy 0]

it would be worth while taking off the water pump also to make sure its in order. Also while you have that off check for any blockages in the pipes leading to and from the rad + pump

 

all been checked..aswell as the rubber seal on the cap...cant find any probs..thers air coming from sumwhere? :( the top hose going into the main block is piping hot..we opened the clip a little to bleed any air and there was nothing but air in there! ...head gone.... :(

[Baz2004 0]

Do you have any oil leaks? What about your oil cooler? Did you check your water pump? Rubber seals may appear ok to look at but you wont know for sure by looking, try and get a cap off another VW and try it. .

[Walesy 0]

no oil leaks..oil temp is fine....checked water pump and its fine...the heads in the process of being put on as we speak...i cant see it being the cap but i will but a new one just in case, the head is being done by an ex main dealer who has set up on his own...after all the faffing around ..changing thermostat..doing all other checks...and doing the head....he wants £200 including parts.... :-P ..if anyone wants the number of a bloody good mechanic who wont charge the earth in cardiff...let me know!!!

[Skimask 0]

DO NOT drill holes in your thermostat. This is a BAD bodge and will mean that your engine takes longer to get upto

 

I Don't get that one Henny! Yes the engine will take a little longer (not much) to get up to temp...but engine wear ...come on!!

I'd rather have that thermostat that weeps, it may run slightly cooler - a bonus. WHEN the thermostat does fail, if it doesn't have a hole the engine will overheat....badly, causing much more damage.

[Walesy 0]

AHHHHHHHHHHH....ok..you name it..ive changed it...including the f*&^ing head gasket and the fan is still not cutting in and the car is overheating.....i havent got a clue what to do next ..apart from cry! :cry:

[Walesy 0]

ok...when i say overheating...its running at around 100 degrees ..it goes up to just under 110 then comes back down....the light isnt flashing...the engine doesnt seem too hot...the water doesnt seem to be at 100 (because surly thats boiling point) ....its almost as if the tempriture gauge is lying??? could it be wrong?