Advice wanted (repeat from project thread)

[Dobby84]

I have just repeated this from my project thread to help get some responses as I'm getting to my wits end!


I have been having problems with my rad hoses pressurising so last night I drained the coolant out of the system. I removed the thermostat and checked that it was opening up as it should and not stuck shut. It works fine so put it back in.

Made sure the fan plug was in correctly when I put the rad back in. Bleed the system as per Rusty's http://http://www.s2forum.com/forum/...light=bleeding thread.

Everything was going well as I warmed the car up, Thermostat opened up fine, then suddenly the pressure in the top and bottom rad hose shot up. They were pretty much rock solid. The temp gauge was reading around 90+2 lines. but the rad fan didnt cut in.

Im very concerned that my head gasket may have gone but fingers crossed its something else as its almost brand new and only done a few miles since it was replaced.

There was a fair bit of steam exiting the exhaust though but was hoping that is just condensation as the car hasnt been started for about a month.

Does anyone have and ideas what I can do next before looking into the head gasket?
Does anyone local (buckinghamshire) have a compression test kit or leak down test to check the gasket?

[Rusty]

Get a 'sniffer test' done on the header tank to look for exhaust gases.

Worth noting that the system will pressurise a little bit and will not give a proper reading of temperature unless at the correct working pressure, neither will the fan kick in at the correct piont on the temperature gauge. Worth making sure that it's bled properly using my guide here and then leave the cap on when checking for correct operation.

[Dobby84]

I used your guide last night Rusty, very good one I might add. Going to re-bleed tonight after work and try again.

Never had a car that the rad hoses go that hard under pressure before thats why im a bit worried.

Is a sniffer test something I can do myself or is the kit expensive?

[Rusty]

It's a chemical test on the coolant - you'll be able to buy a kit or just get it done by a friendly local mechanic.

[Dobby84]

It's a chemical test on the coolant - you'll be able to buy a kit or just get it done by a friendly local mechanic.

I dont live near anyone (out in the sticks) Wouldnt want to drive that far like it is.
Just read on another forum that I can syphon off a jar of warm coolant and take it to a local MOT and they will test it for me if I ask nicely.

[avants2turbo]

might be a silly suggestion, but is the coolant circulating? (maybe a dead water pump?)

[Dobby84]

might be a silly suggestion, but is the coolant circulating? (maybe a dead water pump?)

I was thinking that too but not sure how to test it, any suggestions?

[avants2turbo]

is there water returning to the expansion tank from the small pipe on the top of the rad? if so the water is circulating, also, so you get any cold spots? or is the whole cooling system hot when its up to temp?

[Dobby84]

is there water returning to the expansion tank from the small pipe on the top of the rad? if so the water is circulating, also, so you get any cold spots? or is the whole cooling system hot when its up to temp?

Havent had time to have a look tonight but will have a closer look tomorrow if I have time and report back.

[Dobby84]

Balls! Looks like its head off time again!

Right, After checking everthing I could think of and not getting anywhere I eventually took a deep breath and took it to my local garage who kindly had look at it for free.

-First they checked the emissions and everything was fine, well within the expected levels.
-Second they allowed it to cool a bit (lower the preessure in the system) so they could remove the header cap safely to perform a sniffer test. Again this came back negative.

The only suggestion they had was that the head was cracked!

So it looks like its all coming apart again to get the head off for testing and a skim. Really cant afford it but considering biting the bullet paying a specialist to do the work for me.

[pixsaudisex2]

So when engine is warm and if you manage to take the cap off the header tank ( carefully) if its that bad surely water will pump out the water bottle meaning yeah the head or something is broken, cracked..while the engine is running.. ( take it your also loosing loads of water)..

[mcandmar]

I am not really convinced you have a problem, the system should pressurize otherwise the coolant will boil over, and 2 marks past 90 on the gauge is pretty normal for these engines, you will see that stuck in traffic with no air flow through the radiator. But the radiator fan should be coming on at that point.

Now if its over pressurizing and leaking out the cap or blowing off hoses, then you have a problem with the head gasket or a cracked head IMO. In my experience with engine changes and totally dry systems it can take a few heat cycles to work all the air out of the system. Basically you need to let it cool and top up the coolant level a few times before it all settles down.

[s2driveruk]

they can behave strangely for a while until fully bled. Check that you have a functioning thermo switch so the fan can kick in, in my experience these can crud up a bit on the connectors and stop it working, get a length of heavy guage wire and jump the terminals to check that the fan will run, then you are down to checking relays, the actual electric circuit or even a fried fan (had this myself)

[Dobby84]

So when engine is warm and if you manage to take the cap off the header tank ( carefully) if its that bad surely water will pump out the water bottle meaning yeah the head or something is broken, cracked..while the engine is running.. ( take it your also loosing loads of water)..

Sorry I forgot to mension that after about 1 minute with the cap off it did boil over quite violently.

I am not really convinced you have a problem, the system should pressurize otherwise the coolant will boil over, and 2 marks past 90 on the gauge is pretty normal for these engines, you will see that stuck in traffic with no air flow through the radiator. But the radiator fan should be coming on at that point.

Now if its over pressurizing and leaking out the cap or blowing off hoses, then you have a problem with the head gasket or a cracked head IMO. In my experience with engine changes and totally dry systems it can take a few heat cycles to work all the air out of the system. Basically you need to let it cool and top up the coolant level a few times before it all settles down.

I have tried getting it to temperature, letting it cool, rebleeding and repeating the process maybe 5-6 times in the last week or so.

My fan doesnt seem to come on when it should but I get scared that im going to cook it if I leave it getting hotter. The hottest Ive had it is 90+2 marks.

[s2driveruk]

when did the fan run last?