New xj milky coolant

[411vm]

G'day

I bought a jeep xj last week it's an 01 with 165kms and has 0630 head.

I took it for drive on some slow trails the other day to give it a good test and see what problems I can find. Once the temp got over 100 it started to boil over so I stopped and let it cool down and continued on. It done this about 5 times on this slow section each time I pulled up and let it cool down. I got it on the open road again it was fine. I got it back home used it to go up the road a few times seemed fine however yesterday I checked the coolant overflow and it is milky looking, but it doesn't seem to be using any coolant


Done some research on it and looks like it might be a blown head gasket (hopefully) or a cracked head.

What do you guys think the best way to attack this is?

If it is just a head gasket what things should I check/replace while I have the head off?

[LuluBelle]

Is your oil looking milky? get the head shaved and made true again while off
as far as getting hot whats the condition of your radiator and water pump check the thermostat as well may as well do the lot while its in bits
_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_)

[rustynuts]

If you have the dreaded 0630 head, check for a crack near the rockers. Usually it occurs between cylinders 4 and 5. If you remove the valve cover you may be able to see it. Often coolant is evident where the crack is.

[Billnick]

Its boiling just over 100* because the cooling system is not holding pressure. This could very well be a blown head gasket, but also check/replace the radiator cap.

If you remove the head you will find removing the lower bolts on the intake manifold a pita. Having just done this, a tip is to leave the manifolds on. The fuel pipe can be pulled off the injectors and set aside because the 'quick release' connector has 4 tabs that need depressing at the same time, so unless you have the correct tool, leaving it on is an option. The next will be the rear right head bolt. A tip there is to nip a few threads off down to the level of the lock nut for the earth strap. Once you move the injector wiring and heater pipes you can get an angle grinder in there with a 1mm cutting disc. An essential tool is a 13mm 12 point deep socket for the head bolts. While you're there get a 16, 18, and 21mm sockets for your standard tool kit, you will need them if you diy. Good luck with it.

[Grippy]

It could have had a coolant leak and the previous owner poured some stop leak sort of deal in, I've seen some that make the coolant very milky

[Billnick]

Originally Posted by rustynuts

If you have the dreaded 0630 head, check for a crack near the rockers. Usually it occurs between cylinders 4 and 5. If you remove the valve cover you may be able to see it. Often coolant is evident where the crack is.

Ummm, 0630 are the good ones, 0331 are dodgy and crack between 3 & 4.

[aaronm]

I replaced my 0331 head on my 2001 xj with the head from the 4 litre wj grand Cherokee. Its the factory fix for the 2001 head crack problem, its an 0331 head but must have TUPY cast into the head near the rocker towers.