[illavitar]

Hey guys,
I got an issue with my 1988 jx Sierra which I just bought the other night! It overheats after a few minutres after running and the owners weren''t really sure why but they suspected a blown head gasket as they had replaced the thermostat which didn't fix the problem. So I got it home on the trailer and checked the oil and it's like a grey/clay colour which wasn't good.. so then I took the cap off the radiator and the coolant looked rather good, a nice bright green haha. I'm thinking coolant has mixed in with the oil hence the gray colour but the coolant in the radiator looks very clean so I'm not sure what to think! I hope it's not a head haha I just did the one on my falcon and I vouched I wouldn't have to do one for a long time!! Any help would be greatly appreciated cheers

[DMAC]

Your self diagnosis is correct.
The good news is a sierra head gasket replacement is a realitivly simple and cheap exersice.

Have the head checked before putting back on.

When you finish post up that it won't start and we'll tell you your timinig is 180 degrees out.
Most of us who have done the head gasket have got the timing wrong.

[jdk81]

Also you will most likely ask us where the vacuum hoses go

[Rusho]

jdk81 wrote:

Also you will most likely ask us where the vacuum hoses go

....and why it idles rough!!!

[Rusho]

In all seriousness, do as DMAC said and I your unsure mark all your timing positions etc before you disassemble it