406oc.co.uk

hi everyone,
i have a 03 plate 110 hdi 406 that last year was blowing all the water out the filler cap of expansion bottle. had new head gasket skim timing belt etc £700 + pounds worth. wife hardly used car so sold second car and started using it myself only to discover same problem. been back to mechanic who claims not head gasket problem will either be head cracked or cylinder liner cracked.
my problem is when he stripped it there were 2 snapped head bolts and when i checked the reciept there are no new bolts on reciept he claims they came with head set but hes prices match the qoutes i got without head bolts.
my question is could there be something else causing similar symptoms ie thermostat fan not working properly temperature sensor. i ask this because occasionaly it will say engine overtemperature shortly after starting and the gauge drops to zero but when it bounces back the reading is normal.
any hints tips advice welcome as desperate to get car sorted spent a lot on it dont want to get ripped off any more. i am a maintanence engineer myself but it has been years since working on a car and they have changed a little everything being computer managed now.
thanks for any advice in advance.
rob

Firstly, If the temperature is reading high with the engine cold, this is an indication that the temperature sender unit is faulty, (coolant temp sensor).

How much water do you have to put back in when it gets blown out of the filler? If it is only a little, maybe the level is too high to start with and it's forcing out what it doesn't need.

Does your heater work properly? Is it cold or varying between cold and hot?

Did you get charged for a new thermostat?

My advice would be....

1)Fit a new thermostat and temp sensor then bleed the cooling system.

2) Run the engine until it gets to normal temperature and check if heater works correctly.

3) If the heater is working right, then run the engine some more to see if the fans come on.


If you still have problem with the water blowing out of the filler, take your car to a garage and ask them to do a "sniffer" test, this will tell you if there are exhaust gasses in your cooling system, showing further head gasket, cracked head / block /liner problems.

Of course, you may want to do this "sniffer test" before doing anything at all.