Head Gasket Question/Advice

I've been nursing a bad head gasket until I can save enough money to have it replaced. It is a 99, 4.0, automatic. I've been keeping an eye on the oil and up until yesterday it was looking ok. Now it is milky. Based on my experience working at Ford, once it got milky we usually ended up replacing the engine. What has been your experience with the 4.0? If I replace the gasket and flush out the oil do you think it will be ok? I don't want to replace the gasket and then end up needing an engine. While it's apart I will have the head checked too. I was also thinking about doing it myself but I am limited on available time. Is it a bad job to do? Any input and advice will be greatly appreciated.

the 4.0 is a very durable engine. i would flush the oil out as soon as possible. the oil coolant mixture will turn to an acid and eating the bearing in time.get the head gasket done like now. there not that bad to do. head is just a little heavy and long.

Coolant mixed with the oil is hard on engine bearings.

It is hard for us to comment "specifically" on your situation as every problem is different.

Any change in your oil pressure readings? If this situation continues, you will probably see the oil pressure drop indicating more severe internal problems.

Have you confirmed the headgasket with a compression test? Low readings on two adjacent cylinders is a good indicator here.

Bottom line is that you want to resolve this right away. And if you pull the head, have it checked by a machine shop that specializes in this for straightness and for cracks before reinstalling it. Money well spent.

I'm going to change the oil tonight and see what it does. Hopefully it will be ok, it was only driven one day with it milky. It is definitely either a bad head gasket or cracked head, I am adding about a half quart of fluid every day and it isn't leaking.

if driven for a short time, probably alright. I would fix it before you drive more, or you will wipe out the bearings.

Likewise.

If you are going to have to wait any significant amount of time before fixing it, I would drain the coolant, unplug the ignition coil and fuel injectors, drain the oil, fill it with new clean oil, and crank it over for a bit to push new clean coolant-free oil through the engine and wash any residual moisture out. The corrosion it will save on the crank and rod surfaces is well worth it.

kastein said:

Likewise.

If you are going to have to wait any significant amount of time before fixing it, I would drain the coolant, unplug the ignition coil and fuel injectors, drain the oil, fill it with new clean oil, and crank it over for a bit to push new clean coolant-free oil through the engine and wash any residual moisture out. The corrosion it will save on the crank and rod surfaces is well worth it.

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All good advice, and Kastein has laid out the best path to follow.

I changed the oil last night, it was milky but not foamy. It was only driven a day that it was noticably bad. I'm sure it has been contaminated for awhile, just not real bad. Anyway, changed the oil and filter, ran it for a few minutes to get the fresh oil circulated and it seems to be ok. No rod knock yet. I'm going to pull it apart hopefully this weekend. Based on everyones experience will a Haynes manual give me all the info I need to do the head gasket?

Haynes = Good underwear
Haynes = Bad manuals

Known to be awfully generic and contain some errors IMHO.

I like the factory service manual, especially for something like this...............

birchlakeXJ said:

Haynes = Good underwear
Haynes = Bad manuals

Known to be awfully generic and contain some errors IMHO.

I like the factory service manual, especially for something like this...............

Click to expand...

x2

You can get the FSM on CD for around $45 (that's including shipping) and it is worth the extra money. check bishko; http://www.autobooksbishko.com/


I bought a Haynes manual when I bought my XJ. It is now being used to wipe shit off my hands and will eventually end its life as kindle for a fire.

I down loaded everything from Mitchell On Demand at work. Unfortunately I wasn't able to get to it over the weekend so it is scheduled for next Saturday. Keeping my fingers crossed.