Water in the oil

[Little Jo]

Hi gUYS

I was worried when I found water in my oil and also in the oil filter. So the first thing I did was drain the water out of the radiator and to my surprise it was clean and had no rust or oil in it. Then I drained the oil out of the sump and that was all milky so I knew it was contaminated with water.

Well I took the plunge and removed the head today and found the following:

1. The gasket seemed OK but when you pressed it water came from it.
2. Number 3 and 4 pistons had about 2 mm water on top of them
3. The thermostat looks like it will have to be replaced as the thermostat housing just disintegrated when I removed it.

I have attached some photos after I removed the head and before cleaning out the water on top of the pistons. Now do I just replace the head gasket and pray all is well or is there something else I should be looking at as well while it is at this stage.

Cheers

Tony

[Richard Farrant]

Hi Tony,
I would check the head for bow or irregularity with a straight edge and even if it appears alright, still get it refaced by a machine shop. It is common for the heads to warp. When you renew the gasket, re-torque after a short period. Torque figures are in the TM, they differ for nuts and studs.

The leak in to the cylinders could have come from the small hole between the two wet cylinders, not a lot of sealing surface there.

regards, Richard

[Little Jo]

Hi Richard

I spoke to my brother who is into classic car restorations and he suggested I give the head to him to take to his guy who machines/shaves heads and checks for cracks. I knew it was not good when I saw the water sitting on top of the number 4 Piston. Well the checks start now, but I have a gut feeling it won't be an easy fix.

Cheers

Tony

[Mike Kelly]

Tony

When it comes time to assemble the head to the block , use a product called HYLOMAR on both sides of the head gasket. It comes in a aerosol can and is available at most auto stores . The paint on version is not as good for head gaskets as you need an even coat .

Mike

[Lynn Eades]

Tony, I would suggest it is time to;
1. descale the block.
2 shout it a valve grind, or you'll be back in there soon. the valves don't look that great. maybe it's the water?
3. give careful attention to the threads in the block.
Does it have bolts or studs. Myself, I would go for studs and nuts with hard washers.
If you had, and want to stick with bolts, I would consider a new set for the maximum contact area (which will help to prevent a thread being pulled in the block.
Do NOT be tempted to over torque it. You can go back and re torque it a few times. I recommend you do, but don't go over, on the torque.
A lot of the flathead V8 guys suggest not tapping the the block threads, at least not with a new tap, but rather with an old worn tap, or with an old head stud with a groove ground in it, so that it functions like a tap. The idea is to clean the threads, rather than cutting metal away. Is that clear enough?
Old flatheads need a bit of special care. They can be a bit temperamental. If you buy head studs they should come with a "bulge above the block thread that tends to stop water leaking up the stud, and out at the nut and washer.I would still apply a quality sealing compound to the studs when installing them in the block. The torque figure for installing a stud is quite low. Seek advice from your (older, caring) engine reconditioner.
Your old head gasket was (I assume) a copper asbestos one. The asbestos does absorb water.
The care Richard was talking about with regards the head, also applies to the top of the block. Use a straight edge and check your block length ways, and check there are no depressions at the thin bits between cylinders 1 and 2, and between 3 and 4.
A quality composition gasket might be a better bet, but as everything is a compromise, and it may come down to availability. your copper asbestos one was easy to remove, right?
Not wanting to be a doom and gloom merchant, but milky oil is the result of a lot of water in the oil. The jeep block is prone to cracking around the distributor boss. This is a possibility, I think more common in the Ford block. Check this out.
You may have a crack down low in one of your cylinders. Check.
Usually the compression pressure forces compression gases into the cooling system, and when the head gasket leak is bad, it blows the water out fast. The cooling system pressure is only 7? lb. Not much compared to combustion pressure. This is why I would check further. (if it was blowing the water out badly, it can let the water run into the cylinder when it's stopped, but usually the water blows from the radiator, before it gets bad enough to put a lot of water in the oil. This does also depend on where the gasket has failed.
Take your time to find the correct answers. Good luck!

[Little Jo]

Hi Mike and Lynn

Thank you for your good advice. I will not be rushing the job and will take your suggestions on board as I progress. As you guys have stated it might now be a good time to do those extra jobs.

I think the water leak is relatively new as when I checked the oil about a month ago it was OK and I have only taken the old girl out for a 20 kilometre spin once since then. I didn't notice anything strange as the old girl was purring along OK and there was no tell tale smoke from the exhaust.

The head had bolts and I was thinking of changing them to studs. The bolts still look OK and still have good threads, but I am not sure if they can be used again as I would not like to think I snapped one and had to go all through removing the head again and drilling out the shaft. So I think I will go slowly, and check everything as I go.

Cheers

Tony