Matty_Boy

ive been trying to get rid of an air lock in the coolant system for the last 2 days and it wont seem to go, its doing my head in now! and ive spent loads on coolant! i have the cap off the tank, im revving it for 30 secs every 5 mins or so to get the air out then topping up again with coolant am i doing something wrong???

thanks

joz8968

iTrader: (13)

- Drain coolant off by undoing bottom hose - collect it in a large, clean washing up bowl for reuse.

- Reconnect bottom hose.

- Disconnect the narrow hose form header tank to rad's top air-bleed plastic nipple (NOT the slightly narrower hose that ultimately goes to the expansion tank by the battery).

- Disconnect the hose on top of the header tank (this feeds the turbo water jacket).

- Wedge a funnel in the end of this hose and slowly fill up with the collected coolant (using a measuring jug or similar to make life easy). Try to temper the flow so that you always have coolant showing in the funnel (so as not to introduce any unnecessary air).

- Fill until the header tank as near full and until coolant flows out of the rad's bleed nipple..

- Quickly reconnect that narrow rad hose, then connect the turbo hose to the top of the header tank.

- That should have prevented airlocks, as it's sort of filling from the bottom upwards, expelling air as you go.

- Turn heater on to full hot and run engine until gauge gets to normal middle position.

- Then wait for about 10mins and squeeze and feel temp of bottom hose until you feel it get warm, then hotter.

- Wait to see when fans kick in and double check temp gauge and heater. If gauge still in middle position and heater very hot, then all would appear good.

- Take out for an extensive test drive, monitoring temps.

- Re-top up as necessary the next morning by the same method mentioned and all should be okay...

Matty_Boy

thanks for that mate, will have to wait till next weekend to try that now, is it bad to drive the car as it is? basically i go to and from work, by the time i get to work the temp gague is just starting to get near the top

Matty_Boy

or i might just ring the garage up as i just paid them £300 to fix this problem and its still happening!

joz8968

iTrader: (13)

No. If it was staying at middle, then fine. If it's at the top when you get there, the temp has got to 120deg + !. If you have to drive to work tomoz and it goes to top, is it wet on the battery tray? If so, then the header tank cap has opened (because of the temp,therefore pressure) forcing coolant out into the expansion tank and overflowing. This would point to your airlock theory... or could be stuck/slow stat, knackered water pump... or HG!

Matty_Boy

yeah it is wet around the overflow pipe area or just around it. the water pump has just been replaced as it was over heating and the garage collected the car and fixed it, well it was running ok for about 2 weeks then it started to over heat again

joz8968

iTrader: (13)

I take it when tou had the pump replaced, as a matter of cousre the garage at lease tested the stat?! Ideally whilst pump was off, should've had stat replaced too!

Aside from then, then 3 other possible things: airlock or blocked rad... But, unfortunately, my money's on HG failure ...

Matty_Boy

they didnt say to be honest, could this be head gasket then?? if so how much is something like that?

kevin wrx

iTrader: (1)

any garage should tell u wat they have done so i no wats been replaced to have cured the problem

joz8968

iTrader: (13)

With checking over of heads and a clean, light skimming of head and block mating surfaces, all new accessible gaskets/seals and other sundries/consumables, two new steel HGs, labour for engine out/in/prep work, then you're talking about £1200+ (depending on garage's hourly labour rate). Competetitve rates are £47.50 + VAT...

Matty_Boy

Jesus! i pray its not that then or the car will be off the road a long time!

joz8968

iTrader: (13)

Nobody's ever said this Scooby lark is cheap

I fit makes you feel better my HG just so happens to have gone and I'll be paying that (and than some) to get fixed soonish...

Tucker82

iTrader: (7)

It is not cheap, as I found out and I did mine myself. I would test the stat, try to remove a possible airlock, flush the rad through, you can even have these tested with a heat probe to determine if they are blocked. Do all that first before you even think about HG failure.

joz8968

iTrader: (13)

Yes, exactly as Tucker has said... ONLY consider HG replacement when you/garage/specialist have exhausted all other possibilities...

Matty_Boy

ok cool, well hopefully he can look at it over the next few days and ill see what he says. cheers