How Do I Know If The Head Gasket Is Blown

[finest1]

hi all

sad news. my gs300 mk1 was diagnosed with a broken radiator and a blown head gasket. the aa man was kind enough to tow me home.

one of my friends was saying that he does not think its the head gasket, as the car would be in a worst state.

i read the thread on overheating, but can anyone give me tips as to how to tell if the HG is gone. this way i can tell the mechanic as he is taking on board what the aa guy said.

thanks

[TheDon]

there will be a creamy mayonaise under you oil cap... and oil in your radiator/coolant fluid

[finest1]

thanks for that

the car engine has been off since 13:00 today

i have just checked oil cap and there is no "creamy" substance.

anything else i should check?

thanks in advance

[Steve ( West Mids )]

How far did you drive it when it was overheating? Normal symptons are creamy as above, possible loss of compression, possible misfire.

[TheDon]

what were the circumstances surrounding the "diagnosis"

[finest1]

hi

thanks for the responses

car was running ok monday night.

today (tues) i set off to work as normal which is a 3 mile journey to work. i decided to put the heating on but cold air just came out. i started playing around with the temp and fan etc, but it was just cold air. journey was steady 30-40mph max in town driving. after 2 miles the warning light came on. i reached my destination and pulled up. i read the handbook to see if there is anything i could find to trouble shoot. my eye fell on the temp guage which was on H. i quickly turned off engine. i then checked biege coolant box which was empty. i refilled and went to work. came back 90 mins later, and switched on. after a minute temp guage went halfway. i fiddled with the heater and no heat. then temp guage crept over halfway. i turned off engine and checked coolant box. empty. i looked at the floor and floor was wet. i refilled with water and found the radiator leaking.

i phoned AA. AA came and put some chemical in the rad. this didn't stop the leak. aa man then done sniffer test and gas came out green, which he said is the head gasket. during the diagnosis the aa man left engine running without cap on radiator. then got towed home.

one of my staff used to be a mechanic. he was with me when i phoned the aa. he was shocked to hear that the aa man said it was a blown head gasket. he said if that is the case, the car should be in a worse condition.

in the afternoon i had already phoned my mechanic and told him, and he said he could do the job. but my staff (david) told me to get a second opinion and let mechanic know before he orders HG.

this is why im enquiring about diagnosing HG.

thanks for the helpful comments/replies

[Steve ( West Mids )]

Well if the AA guy has done the gas test then I'd say it's pretty conclusive. Worth getting the mechanic to double check before he does any work you may need to get it towed to the garage to avoid any further damage.

[Monster-Mat]

get a compression test done.....first

[finest1]

will my mechanic do the compression test? he needs to change the radiator anyway

[bigdavegrr]

Should imagine so if you ask him.

[TheDon]

Was gonna say it seems more like a coolant issue.. is the GS run with a heater matrix for hot air? Could some of the leakage be there? they do go on a lot of cars.

Seeing as it wasnt run massively hot for a long time there could be a saving grace there... Getting the coolant system sorted and then re-checked would be interesting.

Good luck with it all though

[wow300]

lots of steam out the exhaust ?

cream oil cap or dip stick ?

missing ?

pressurising rad, expansion bottle ?

check your thermostate is not jammed shut.

[TigerFish]

What does your friend mean when he says the car would be in a "worse state"?

The mechanic should be able to do a compression test, of course he will have to remove the throttle body etc to be able to compression test all of the cylinders (make sure he has new gaskets for the throttle body for re-assembly).

[wow300]

Ya mine still ran perfect !

[finest1]

thanks guys,

i spoke to the mechanic today who asked me a few questions. from the answers i gave he thinks its not the head gasket, but in my mind im telling myself it is, so there's no suprises. there is definatley a leak in the radiator as it just leaks water the minute i fill it.

again, no cream like substances, or smoke out of the exhaust. anyway, car will be going to him in a few days, so i hope its just a radiator. i'll keep you posted

thanks again

:mellow:

[lexluther-return]

Hmm May not be the head gasket, compression test is the way to go.

Hope its not and rather a bad hose or matrix.

Regards

LL

[finest1]

hi all,

just to give you guys an update.

ended up being just a radiator fault. myself and mechanic wondering why AA man told me it was head gasket.

mechanic told me that the fact that i turned engine off the minute it started to overheat saved the engine.

car is running ok

phew !

[TigerFish]

Nice result B)

[jackhunt]

hi all,

just to give you guys an update.

ended up being just a radiator fault. myself and mechanic wondering why AA man told me it was head gasket.

mechanic told me that the fact that i turned engine off the minute it started to overheat saved the engine.

car is running ok

phew !

Hi, I'm going through the exact same thing with my IS200, how reliable are these tests which make the water green? My car seems fine and my mechanice said he's sure the head gasket has not gone.

I'm very confused...

[abtx]

11 years later, my GS430 has the very same symptoms, but also for a moment there was creamy substance in the leak the AA guy said could be transmission or servo fluid. I hope it is just the radiator too, not new head gasket or auto box...

[stox]

Having got it fixed I would keep a very close eye on the coolant level for a week or two. Check before the first start of the day and then again at the end of your journey when the engine is warm - maybe mark the reservoir with some tape, The cold level shouldn't vary at all, and the hot level shouldn't shift much either.