Blown head gasket and water from expansion tank.

See my comment on the buyers guide topic.

I didn't want thet string to become a general chat so I statred a new thread here.

Chrisandhiace, you mentioned that water coming from the expansion tank is a sign of the head gasket blown. As I said thats what happened to my SC. When I get it back I am going to remove the head and see whats what. I will inspect the water pump, thermostat, and radiator. Guidance would be appeciated in what I need to look out for. How to test the rad, for example.

Looking forward to getting it back on the road or getting another one.

Simon

PS I should of taken a pic of it on the German AA truck for the photo comp!!

Hi there,

I had a similar problem with my Van, every so often water would come from the expansion tank. This gradually got worse and more frequent. I took the van to a radiator place and they removed the rad cap and fitted a hand pump & pressure gauge. They pumped up the system and water was coming from the radaitor LH side. I sourced and replaced it with another radiator and that fixed the problem. So an expansion tank that overflows can be a sign of a leaking head gasket (as the engine pressurizes the water circuit through a leak), it isn't always the case. When I got the second rad I had it pressure tested before I bought it, the Rad place did that cost $70, but was worth it as its a hell of a job to change the rad.

Also, if it is the Head gasket leaking there may be oil or oil residue in the water

Best of luck with your problem.

Martin.

Thats the only 2 causes....on the second the coolant system 'sucks' air in on the cool down (vacuum stage)...radiator pin hols, gasket seals, hose fittings etc.
Simongd....I'm not really in a position to offer advice but having the system fully pressure and vacuum tight is essential.
When off the head will need crack detecting fluid and checking for flatness etc...maybe a skim....gaskets come in different thicknesses to make up for skimmed heads.
If you are keeping her you may want to consider a new water pump etc. while everythings in bits.
Not sure what engine you have but the 3L model engine manual is online and tells all you need for a head rebuild

Start engine and then remove coolant pressure cap. If there are loads of bubbles then it is a cracked head/blown head gasket. If hardly a buble then a leak.

NOTE if you have a leak and the water lever drops you will overheat to some extent and force coolant out under pressure.

Fingers crossed it is a leak - best looked for with the engine running and hot on a dark night and look with a pencil beamed torch, easy to spot a small puff of steam that you would not see in day light and evapourates leaving no trace when looking.

The bus arrived home this week. I have started stripping the engine, but what you have just said Clive and my cousin noticed a rust streak on the rad I am now wondering...

I mean, the day before the cap blew, the engine was loosing water and over heated. When I switched off the engine water and steam were coming out the expansion tank hose with some force. When I started the engine again it stopped. I suppose that just means the water pump was doing its job.

The Another thought I had was that the spring on the cap was old a weak and allowing water to escape.

Perhaps I ought to have the rad pressure checked before disturbing the head.

i would.. last thing you want to do is a head...

One thing i forgot to mention yesterday is that my missus noticed a drop of oil on the tarmac where the car was before being put on the recovery truck. I suppose that would piont to a gasket failure.

Some one at work has one of those cameras fixed to the end of a flexiable pipe see if i can borrow it.

One spot something to keep an eye on, wouldn't worry at this stage.

Gasket/head failures on these engine are normally between the cylinders and most likely to be water and only while hot and under pressure.

Thanks everyone for your input.

I think I found the source of the oil. A breather pipe that goes round the back of the head and above the gasket, so oil is unlikely to have come from there (and like you said Clive about between the cylinders).

I tested the thermostat today and it only starts opening at 90oC (manual says 86starts to open) also quite stick. I don't think this is the only cause I have seen a rust stain on the driver side of the rad.

Will do the bubbling test Clive described in the 4th reply and take it from there.
Simon

PS I saw a nice 1999 SC in Hampshire on ebay... tempting...

OK

I warmed up the motor last night. didn't bother putting the thermostat back in cause I wanted (or didn't want) to see bubbles. I was supprised though that there was only around 3 litres of water missing. I thought it was dry.

What I did discover was a leak on the rad (drivers side) near the top.

There was also a 'froth' in the thermostat housing.

I was suprised that the water wasn;t being forced out of the thermostat housing like I imagined. I was expecting to see a positive upflow of water out the top of the engine and into the radiator, but there was nothing. Is this right?

Obviously I don't want to take off the head without being sure it is nessacary. Step forward from here I am going to take off the rocker cover to look for emusion (none on the oil cap) then I think I am right the pressure reading of the compression of each cylinder will tell me. Probably have to ask a mechanic to do this.

ttfn

With the cap off, when you rev the level drops...and rises on return to idle.
Get the engine hot and observe......with some ingenuity you can extend the cap head into an inverted top up bottle if you like
If you have a problem you'll have bubbles...would'nt worry about froth or initial purging of air.
Personally I'd sort the rad leak, renew coolant, fit new correct thermostat and try using it........see what happens

Hi There,

What you are suggesting is exactly what I did when my SC was blowing out water from the expansion bottle, except I didnt change the Thermostat, just replaced the Rad, replaced the coolant with new - and fitted a new pressure cap also topped up the Auto transmission fluid as I lost some when I changed the Rad (as it has a Auto oil cooler fitted).

I'm going to try radweld first. I know its a temp fix but if it means I find out the head + gasket are fine then I will shell out for a new rad.

I bought a new water pump off ebay last night for £26!

On another note I got myself a petrol chainsaw this week... I'm a lumberjack an' I'm alright... (everybody now)...

Don't use Radweld use K-Seal.

Not heard of that before. Can I get it from a motor factor?

yes, or ebay...

Yes Kallimax K_Seal around £10.00 a dose and has worked wonders on coolant loss problems.

Issued to our boys in Afghanistan in case they spring a leak while on patrol, can't get a better endorsemenr than that!

The problem with the rad sealants is the unused part sinks to the bottom and then can clog the waterways.

Now I have got an action plan.

First I'm going to clean the coolant system with one of those two part cleaner stuff. Recomendations on which one to used greatfuly received.

Then, take the hoses off and flush the rads through with a hose pipe.

Change the water pump and thermostat.

Add K seal and coolant.

Hopefully job done then.

If its good enough for our boys abroad then its good enough for me.

Quote :

If its good enough for our boys abroad then its good enough for me

The problem is a lot of stuff they get is'nt good enough...but thats going off topic...

Its been a crazy fortnight doing double shifts at work, but at last I have time to work on SC again.

Right, so I have done the Holts engine cleaner thing and put in K Seal. Unfortunetly the hole in the rad has not been closed up by it. I can see K Seal deposit around the hole, but seeing it again today the hole looks more like a split, so I am not suprised.

The good news is that there is still no sign of head/headgasket failure.

So looks like I have to take out the radiator and see if it is fixable and pressure test it. Oh and I will do the second radiator at the same time.

Has anyone taken both the rads out of an automatic. I believe the first rad has 7 hose connections!

OK then.

All the hoses are off the rad and it is now free. Unfortunately lack of light stopped play so I will try to remove the rad tomorrow.

Forgot to mention yesterday, I didn't need to change the water pump, it seems to be working fine--- thank goodness.

I have also found a place in Liverpool that will pressure test, caustic clean and patch (if possible) it for £35.

Also, tonight I noticed there are not 2, but 3 radiators. There are actually two lying horizontaly, I suppose one secondary rad for the engine and an aircon rad. Has anyone taken these off? I have loosened the bolts holding the support frame but there are air con pipes attached between the rad and chasis. Going to have to find a way I suppose, or else I get a mobile mechanic to pressure test them in situ (sounds like the better option)

How on earth it got into this state I don't know, cause brass doesn't rust. Perhaps it eventually becomes brittle with age and expansion/contraction cycles.

There are multipule fractures on the off side tank. I doubt it is repairable but I will take it to a specalist and see what they say. In the meantime does anyone have an spare rad?

Where can I buy one, breakers, yes but it might not be any better than the one I got.

There should be someone there that can recore it surely.. You will have to regas the aircon too when you get it all back together.

I have got my radiator back been recored and the tanks reconditioned. back on the bus now just a few more bits to bolt on before firing her up.