Head Gasket

[chatlow 0]

Hi

I am in the process of removing the head so that I can replace the gasket. Can someone please tell me what order the rocker cover bolts and head bolts have to removed in?

Also do I need to touch the aux belt and timing chain when carrying out this job?

Lastly, does anyone know if the yaris gs 1999 1.0 has an ODB capable port so I can read the engine code?

Thanks

Rod

[Devon Aygo 848]

* Never seen or heard of a head gasket fault on a pertol Yaris before what is your fault/symptoms?

* Yes the aux belt then timing chain case & timing chain are going to have to come off

* Yes is does have an obd port behind a pop off trim on RHS of the dash by drivers knee

Devon

[chatlow 0]

poor running (lumpy acceleration) but the main issue is white/cream in the coolant (both under the rad cap and in the expansion tank)

compression test has come back ok. all cylinders between 180 and 190. havent got any other test i could use to be sure so just going to carry out the HG replacement.

managed to find a white port under the drivers side and my obd cable fits to it but unfortunately I cant get any free obd software to recognise it.

with the timing chain is it just a case of marking on the cam and the chain before taking it off?

[Madasafish 130]

The timing chain is already marked - in yellow iirc.

The Haynes manual covers the cylinder head/timing chain removal replacement very well.

[chatlow 0]

great, thanks. so if its marked, then i just need to mark then same points on the cams before removing it yeah? sorry but this is my first head gasket replacement!! got the haynes manual arriving in the next few days.

is there anything else i can do to be sure its the HG thats failing? the compression is fine but like i have said in a previous post/thread, there is grey/white cream in the coolant. i don't think the engine has overheated to cause the failure so i really need to know what caused this. any ideas? just before it went i drove 25 miles in the cold and the blue light never went off.. so would this indicate a faulty thermostat? sensor was replaced by prev owner a year ago. only other indication that something is up is the engine light turning on, but i havent got a way of reading the code.

any advice would be really appreciated as i will be fixing (or trying to) this weekend. ordering parts later today.

thanks

rhodri

[Madasafish 130]

Faulty thermostat.

Cold engine = condensation in Oil = white mayonaise.

[chatlow 0]

Appreciate that, but its Oil in the coolant more than water in Oil... Its like cream under the the rad cap and in expansion tank