Does A Pressure Test Show A Faulty Expansion Tank?

[irishjay]

well my avensis has beeen losing coolant a litre every week , mr t done a pressure test and it came up all fine they have been told my MR T GB to do a head gasket test because its a common fault ,this morning i heard a hissing noise coming from the expansion tanks lid so i put my finger over the overflow pipe and next thing started to bubble and hiss from the lid , i want to know if the expansion lid was faulty would that come up on a pressure test????????im going to MR t tomorow and will certainly be telling them this

[igormus]

well my avensis has beeen losing coolant a litre every week , mr t done a pressure test and it came up all fine they have been told my MR T GB to do a head gasket test because its a common fault ,this morning i heard a hissing noise coming from the expansion tanks lid so i put my finger over the overflow pipe and next thing started to bubble and hiss from the lid , i want to know if the expansion lid was faulty would that come up on a pressure test????????im going to MR t tomorow and will certainly be telling them this

each lid has safety valve to lose the pressure inside the cooling circuit , especially in hot summer time. but in case you have observed gases passing thru this lid then it is a signal of head gasket burning out. this lid must be always tighten.

cheers

[gazza1286]

If you paid good money to Mr T for doing a pressure test and they were aware of the loss of coolant I am surprised that they didn't check for problems in the head gasket at the same time.

This test is normally known as the 'sniffer' test. A liquid is used to test for hydrocarbons in the cooling system. There is no labour cost involved with this test. Similarly did they not do a compression test at the same time? How much did you pay them for this?

The water pump on these cars is regularly to blame for loss of coolant. This would only show up with the engine running. Again, I'm surprised thet Mr T didn't look at this as well?

[irishjay]

thanks for answering , i brought the car in to get checked for a rattle and when i was there i told them about a loss of coolant , they tested injectors said one was faulty its getting replaced tomorrow ,they performed a pressure test on the vehicle and said that there was no obvious signs of coolant loss and that there was no drips anywhere ,they told me they would ring me when injectors come in , so on monday they rang and said the part is in , also they said that toyota gb had told them that when the car is in to perform a head gasket test as it was a common problem , so they are doing head gasket test tommorow , this is all being done under warranty as the car has 50k on it , are you telling me that the expansion tank lid should be hissing from the lid???????

[igormus]

thanks for answering , i brought the car in to get checked for a rattle and when i was there i told them about a loss of coolant , they tested injectors said one was faulty its getting replaced tomorrow ,they performed a pressure test on the vehicle and said that there was no obvious signs of coolant loss and that there was no drips anywhere ,they told me they would ring me when injectors come in , so on monday they rang and said the part is in , also they said that toyota gb had told them that when the car is in to perform a head gasket test as it was a common problem , so they are doing head gasket test tommorow , this is all being done under warranty as the car has 50k on it , are you telling me that the expansion tank lid should be hissing from the lid???????

in case your gasket is burnt out then you'll see an oil film as well as bubbles.

it is required the time to reach the valve opening pressure.

cheers

[irishjay]

cheerz igor cant see any oil film , filled car up again today with water and no sign of oil ,,,,,,,,,,should the lid make noise???????????

[igormus]

cheerz igor cant see any oil film , filled car up again today with water and no sign of oil ,,,,,,,,,,should the lid make noise???????????

the task is too simple -- to locate the guilty part.

ok in cacse you have not an oil film then you must to have gas bubbles right there -- are there any available?

cheers

[irishjay]

i have not noticed any oil or gas bubbles , the only thing i have noticed is that there is a loud hissing noise coming from the expansion lid and when i open the lid there is no visible water in the expansion tank , when i open lid i hear pressure sound

[igormus]

i have not noticed any oil or gas bubbles , the only thing i have noticed is that there is a loud hissing noise coming from the expansion lid and when i open the lid there is no visible water in the expansion tank , when i open lid i hear pressure sound

ok then install a monument to your gasket :) -- it is died

sorry but it is fact.

be ready to change this gasket on new one.

cheers/Igor

PS -- i ve had it on my previous ford sierra 2.3 diesel. the collant has been converted into a steam.

[irishjay]

i have not noticed any oil or gas bubbles , the only thing i have noticed is that there is a loud hissing noise coming from the expansion lid and when i open the lid there is no visible water in the expansion tank , when i open lid i hear pressure sound

ok then install a monument to your gasket :) -- it is died

sorry but it is fact.

be ready to change this gasket on new one.

cheers/Igor

PS -- i ve had it on my previous ford sierra 2.3 diesel. the collant has been converted into a steam.

thanks igor ,, yes you were right head gasket gone after 50k!!!!