Wudduk74

I have a '96 ZJ with a 4.0. It has 155,000 miles. I changed the oil less than a month ago, & it has very few miles on the fresh oil (probably between 500 & 1,000 miles). I checked my oil yesterday & it has water in it. And I seem to losing coolant. Does this sound like the head gasket to you guys, or possibly worse? It has never run hot, so I'm not sure what could have caused this. And it has never been in any water that might have gotten into the engine.

carrasco1

that's what it sounds like to me...i would take it and have a block check done on it...that'll tell u if there is any leaks within the eng or heads...GL i just went thru this with mine

Black00XJ

1. If your losing coolant, have a coolant pressure test done.
2. Have a compression test to establish that one or more cylinders is leaking.
3. Then block test to make sure what you see is water/coolant

Wudduk74

1. Yes, I am losing coolant, just not a lot. There are no places that it is dripping on my carport. Of course I know that there are ways that it could evaporate before it hits the ground (i.e. Dripping on manifold & the heat evaporating it, etc.).
2. The Jeep is running fine. No misses at all. Has plenty of power, so I'm not sure that it has any compression leaks. But I guess that I might as well check it while I am at it. Does any one know the proper compression?
3. What exactly does a block test involve? Never have done one. If my oil is "milky" & I am losing coolant, what else could it be, other than coolant? Like I said earlier, it has never been in any deep water. Never anything much over ankle deep. I have owned this jeep for nearly 3 years & have put over 53k miles on it. The last 2 years it has just been my hunting/fishing/beat-around rig & haven't put but about 3k miles on it in 2 years. But the first year that I owned it, I put over 50k on it, pulling a "Little Debbie Trailer". So the first year was rough on it. Lol

Wudduk74

Thanks. That sounds like the running theme from you guys. I have never done a block check... What does it involve? And what will it check? What kind of a machine do they use? And most importantly.... What will it cost??? Lol

Bustedback

How far do you drive? Does it get uo to operating temp when you drive?

Wudduk74

Yes, it gets up to operating temp. (around 200-210) when I drive it. My trips vary from a couple of miles, to over a hundred depending on what I might be doing. I do not have a commute to work, I teach at the local high school that is right across the road from my house.

Bustedback

Short trips will not let the engine get warm enough to "burn" off moisture inside the engine. Are seeing a lot of milky oil, ot just some crud on the oil fill cap?

dave1123

Try this. Pull the oil drain plug and take a sample after its been sitting overnight. You should be able to see if it's water or coolant in the oil. If it's not coolant, it just hasn't been driven long enough to evaporate the moisture that gets sucked into the engine as it cools. Enough coolant in the oil can break the oil film that is nessesary for bearings good health.

You may also see coolant in the cylinders by pulling the plugs and cranking it over with someone watching what comes out. CAUTION!! disconnect the ignition for this. Try holding a piece of brown cardboard in front of the plugholes to catch whatever is blown out. Gas will evaporate, coolant will not.

These tests are free and are as old as motoring is. If you find a cylinder is suspect, try a compression check. If not, you may have a "Ninja" leak that only appears when the engine is hot. This could be block or head, and will require a pressure test to find it.

FYI, SAE says that an engine should be run AT LEAST 10 minutes after reaching operating temp to evaporate condensation inside the engine. That white milky crap turns black and gooey and is called SLUDGE!!!

Black00XJ

You put a dye just like in a oil leak detection kit. Then put a small tube where your coolant cap is. If there is a leak, the liquid in the tube will change colors.

Black00XJ

And for a compression test, pull the plug wire, hook up the compression tester and have someone attempt to turn it over on each cylinder. See if they run equally or if one is lower than the rest.

Wudduk74

I do make more short trips than long ones. About the farthest I drive it on a regular basis is to The supermarket, which is less than a mile, round trip.

Wudduk74

That makes sense...I will try that this weekend.

Wudduk74

Ok, I never have done a block test. I have done a compression test before, though. Thanks.

Wudduk74

I have to say that I have had to start driving the Jeep more, for longer distances. I checked the oil today & it is clear. Apparently, I wasn't driving it enough to burn the condensation out of it. I will keep a close eye on it & update again later.