Really weird Pressure Problem on Vauxhall Corsa
Discussion
Hi
If anyone can help with following I’d really appreciate it, struggling this end. Vauxhall Corsa Elegance 16V, 1.2L, 2003 Reg. Car worth about £1K max so can’t invest too heavily in garage bills/parts. Having said that…we probably already have! Bit of a long message I’m afraid.
First problem – car was losing a lot of coolant. had to fill up coolant reservoir every week. No visible leaks that we could find. Oil under rocker cover had that mayonnaise look and consistency to it. We assumed problem might be head gasket.
Second problem was that heater was not working properly inside car. It blew out luke warm air but never hot. On this point, we tried flushing water through inlet and outlet hoses to make sure it was clear. Didn’t detect any blockage.
Took car to a Vauxhall dealer who tested head gasket and said it was fine. They reckoned there might be a hairline crack in crankcase behind water pump and water getting in there. This was based on them noting that one of bolts holding it in place was different to others. It wasn’t based on anything scientific. Solution seemed to be get a second hand engine.
We couldn’t see logic. How much water would need to get through a hair line crack to empty the coolant reservoir each week and also wouldn’t oil level rise up dipstick as oil floated on new water before it all burned off? We couldn’t see that volume of water burning off that quickly.
We could only think it still could be a gasket problem. Tried steel seal to fix it, this worked really well for us on a car in the past, saved a lot of time and money. Steel seal didn’t stop the coolant level falling and may actually have caused a problem by partially blocking the heater matrix but we’ll put that aside for a second.
The coolant level continued to keep going down. We changed thermostat and water pump. Heater still didn’t work. We then had a sudden build-up of pressure that forced a load of coolant out of the reservoir (past the reservoir lid) and all over the engine compartment. We could see this as when the water had dried off the steel seal in it had left a white, chalky residue all over the engine compartment.
We could only think a build-up of pressure sufficient to force the water out could have come from the pressure being forced past a weak point in the head gasket and into a water channel. So it was back to the head gasket again.
So we changed the head gasket. No obvious signs of the old one blowing when we took it out. Also checked all of the heater controls and no problem there, all working correctly.
Where we are now:
1. Heater blows out hot air for first ten seconds and then goes back to luke warm. Turn it off for a minute then on again and it does same thing. We’ve flushed water through matrix several times to try and clear out any residue from the steel seal in case that is inhibiting it. First time we did this it did seem to clear some kind of blockage that was limiting the rate at which the water flowed through it and afterwards the heater did keep blowing out hot air. Now though it doesn’t seem to make a lot of difference. We may put a new matrix in as cannot think what else it could be. We’ve checked all components linked to heating/blower controls. All seem fine, it is all based on system of flaps to divert heat, there is no valve opening and closing for example that could be causing a problem. Pipes going in and out of matrix get very hot to the touch
2. We’ve still got problem with pressure build up violently forcing coolant out of reservoir. There is no way to predict when this may happen. Again, a few days saw steel seal residue all over the engine compartment where coolant had spewed out. Interestingly, yesterday I again flushed water through the heater matrix to try and flush out any residual steel seal. When I’d finished, I topped it up the coolant reservoir as it was low. Ran engine and the reservoir started to fill up completely, well above the maximum line, lot of bubbles coming in, eventually it overflowed out of the coolant reservoir. But then about twenty seconds later the coolant level dropped and it emptied almost completely. To a lamen like me seemed as if there was something going on with airlocks etc. Seemed as if pressure was pushing it up into the reservoir then the pressure dropped and it returned to normal. This all happened while the car was running, not after I turned the ignition off
Realise this is a long explanation; it’s been a long process! My daughter wants to sell the car but I don’t want to pass on the problem to someone else, not my way I'm afraid. If anyone has any ideas would appreciate it. I'm obviously wondering if the two problems between lack of heat and this issue of coolant being forced out of the reservoir are linked but that may not be the case. :s
Thanks for any help you can give.
If anyone can help with following I’d really appreciate it, struggling this end. Vauxhall Corsa Elegance 16V, 1.2L, 2003 Reg. Car worth about £1K max so can’t invest too heavily in garage bills/parts. Having said that…we probably already have! Bit of a long message I’m afraid.
First problem – car was losing a lot of coolant. had to fill up coolant reservoir every week. No visible leaks that we could find. Oil under rocker cover had that mayonnaise look and consistency to it. We assumed problem might be head gasket.
Second problem was that heater was not working properly inside car. It blew out luke warm air but never hot. On this point, we tried flushing water through inlet and outlet hoses to make sure it was clear. Didn’t detect any blockage.
Took car to a Vauxhall dealer who tested head gasket and said it was fine. They reckoned there might be a hairline crack in crankcase behind water pump and water getting in there. This was based on them noting that one of bolts holding it in place was different to others. It wasn’t based on anything scientific. Solution seemed to be get a second hand engine.
We couldn’t see logic. How much water would need to get through a hair line crack to empty the coolant reservoir each week and also wouldn’t oil level rise up dipstick as oil floated on new water before it all burned off? We couldn’t see that volume of water burning off that quickly.
We could only think it still could be a gasket problem. Tried steel seal to fix it, this worked really well for us on a car in the past, saved a lot of time and money. Steel seal didn’t stop the coolant level falling and may actually have caused a problem by partially blocking the heater matrix but we’ll put that aside for a second.
The coolant level continued to keep going down. We changed thermostat and water pump. Heater still didn’t work. We then had a sudden build-up of pressure that forced a load of coolant out of the reservoir (past the reservoir lid) and all over the engine compartment. We could see this as when the water had dried off the steel seal in it had left a white, chalky residue all over the engine compartment.
We could only think a build-up of pressure sufficient to force the water out could have come from the pressure being forced past a weak point in the head gasket and into a water channel. So it was back to the head gasket again.
So we changed the head gasket. No obvious signs of the old one blowing when we took it out. Also checked all of the heater controls and no problem there, all working correctly.
Where we are now:
1. Heater blows out hot air for first ten seconds and then goes back to luke warm. Turn it off for a minute then on again and it does same thing. We’ve flushed water through matrix several times to try and clear out any residue from the steel seal in case that is inhibiting it. First time we did this it did seem to clear some kind of blockage that was limiting the rate at which the water flowed through it and afterwards the heater did keep blowing out hot air. Now though it doesn’t seem to make a lot of difference. We may put a new matrix in as cannot think what else it could be. We’ve checked all components linked to heating/blower controls. All seem fine, it is all based on system of flaps to divert heat, there is no valve opening and closing for example that could be causing a problem. Pipes going in and out of matrix get very hot to the touch
2. We’ve still got problem with pressure build up violently forcing coolant out of reservoir. There is no way to predict when this may happen. Again, a few days saw steel seal residue all over the engine compartment where coolant had spewed out. Interestingly, yesterday I again flushed water through the heater matrix to try and flush out any residual steel seal. When I’d finished, I topped it up the coolant reservoir as it was low. Ran engine and the reservoir started to fill up completely, well above the maximum line, lot of bubbles coming in, eventually it overflowed out of the coolant reservoir. But then about twenty seconds later the coolant level dropped and it emptied almost completely. To a lamen like me seemed as if there was something going on with airlocks etc. Seemed as if pressure was pushing it up into the reservoir then the pressure dropped and it returned to normal. This all happened while the car was running, not after I turned the ignition off
Realise this is a long explanation; it’s been a long process! My daughter wants to sell the car but I don’t want to pass on the problem to someone else, not my way I'm afraid. If anyone has any ideas would appreciate it. I'm obviously wondering if the two problems between lack of heat and this issue of coolant being forced out of the reservoir are linked but that may not be the case. :s
Thanks for any help you can give.
Edited by PhilR666 on Sunday 10th February 20:53
Thanks Rooster.
I was concentrating on potential for pressure from piston for example to have forced coolant out of reservoir and so didn't consider potential for it to boil and force out that way.
funny thing is thought, this blowing out of the coolant doesn't happen every time we run the car, it just seems to happen at random times. It could not lose coolant for a week or so then suddenly we notice it has blown out again. But the heater just continues to blow out hot air, then go lukewarm. Turn it off and leave it for a few minutes and then turn on again and yes we have hot air but only for a few seconds then lukewarm again. But as mentioned, this isn't necessarily accompanied by the coolant being forced out of the reservoir.
I'll try changing the matrix as we do have a spare to try and rule out a blockage in there.
Am I right though that if that doesn't work and blockage is somewhere in the engine then id have to change the engine? Or do you know of a product that might help free the blockage?
I will flush fully with water but not sure if that will do the trick. Thanks again for your help
I was concentrating on potential for pressure from piston for example to have forced coolant out of reservoir and so didn't consider potential for it to boil and force out that way.
funny thing is thought, this blowing out of the coolant doesn't happen every time we run the car, it just seems to happen at random times. It could not lose coolant for a week or so then suddenly we notice it has blown out again. But the heater just continues to blow out hot air, then go lukewarm. Turn it off and leave it for a few minutes and then turn on again and yes we have hot air but only for a few seconds then lukewarm again. But as mentioned, this isn't necessarily accompanied by the coolant being forced out of the reservoir.
I'll try changing the matrix as we do have a spare to try and rule out a blockage in there.
Am I right though that if that doesn't work and blockage is somewhere in the engine then id have to change the engine? Or do you know of a product that might help free the blockage?
I will flush fully with water but not sure if that will do the trick. Thanks again for your help
Edited by PhilR666 on Tuesday 12th February 18:40
Hi
we really struggled with this. We couldn't find the fault and do reckon it was possibly a cracked cylinder head letting compression pressure into the water system. The fact that the water had just literally shot out suggested something like that.
We eventually bit the bullet and bought an engine from local scrap yard for £350 and fitted it. All then went well and we breathed a sigh of relief after several months of changing and trying different things and spending many hundreds trying to find the fault
A week later someone drove into the back of the car and wrote it off. No-one was hurt. We sold the whole car back to the guy who had sold us the engine for £125. My daughter got insurance payment.
I'm sure there's a punchline to this story somewhere?! Suppose if I hadn't spent all those days and cash tryng to fix it I'd only have spent them despairing over West Ham's weekly performance
Thanks again to everyone who offered help, very much appreciated
we really struggled with this. We couldn't find the fault and do reckon it was possibly a cracked cylinder head letting compression pressure into the water system. The fact that the water had just literally shot out suggested something like that.
We eventually bit the bullet and bought an engine from local scrap yard for £350 and fitted it. All then went well and we breathed a sigh of relief after several months of changing and trying different things and spending many hundreds trying to find the fault
A week later someone drove into the back of the car and wrote it off. No-one was hurt. We sold the whole car back to the guy who had sold us the engine for £125. My daughter got insurance payment.
I'm sure there's a punchline to this story somewhere?! Suppose if I hadn't spent all those days and cash tryng to fix it I'd only have spent them despairing over West Ham's weekly performance
Thanks again to everyone who offered help, very much appreciated
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