Ok so I'll try and be clear here as there's a bit of info lol please bare with me. I changed my oil earlier this week and noticed a small amount of milkyness under the cap, like a few drops. I thought oh no the dreaded crack, though I have never overheated it (which I know isn't exactly a pre-req for these crappy 0331s). I also noticed my overflow tank was a little low but I have been aware of small, slow leak from the heater hose going to the top of the tstat and have occasionally added to the reservoir but nothing alarming. I noticed it the resevoir was pretty much empty about 2-3 weeks ago and added more then on my oil change on tuesday noticed it was low again which led me to believe that the coolant was going into the oil explaining the off color drops under the cap. Now I get a combustion leak test and go to perform it and as the car is approaching operating temp coolant is coming out of the rad fill. So i realize the coolant is low in the rad so I add more coolant and then get it to normal operating temp and perform the test. fluid stays blue after 2 tests of pumping for more than a minute. This brings me to my first question could this constant small leak at the hose allow for low coolant in the rad even though i monitor the resevoir and fill as needed. Then would a lower coolant level or imperfect seal of the valve cover (because I'm dumb and broke a bolt) allow for moisture in the crankcase leading to those few droplets of discoloration.

Now the other point here is I didn't drain any more oil than usual when I changed the oil on tuesday. Actually a little less. I know I've been leaking oil the spots in my driveway tell me. I topped off the oil a little less than a month ago and I drained a little less than 4.5 qts this past tuesday I noticed no discoloration under the cap when i topped off (I always check when opening) and I typically drain a little more than 4.5 qts. So if I lost a ton of coolant into the oil I'd expect to drain quite a bit more than usual. The dipstick seems to have normal color at operating temp and I don't exactly notice any additional steam/white smoke from the exhaust either. The oil I drained also looked like it does any other time I change the oil so I'd expect there to be a big difference in color in addition to volume if coolant was in it. So now I'm unsure if it's a head crack or just nothing. I can't notice a crack when looking through the fill cap but I also haven't pulled the valve cover. I'm going to tmrw or sunday. My oil pressure is fine. I am going to get an oil analysis but I also really need a car to drive lol. Looking for some opinions here, safe to drive or nah.

I also understand there are people that are going to say just replace the head anyway so please don't say that lol.

 

A couple of drops under the cap is probably just from normal condensation.

 

If I had to guess (and I am guessing), I would say drive it, but keep a very close eye on the coolant level. I would also get that oil analysis done ASAP. You can save the engine if you catch a cracked head early enough, but you can also ruin an engine by letting it go. My stock head was replaced because of a cracked head and coolant consumption when the Jeep had 50k on it. It is now pushing 150k with no signs of issue from the head cracking.

 

find the front valve cover vent...it probably goes to the air inlet hose fitting...remove it from the elbow on the valve cover. Instal a clear plastic 3/8 hose 3 feet long and just let it hang anywhere...in a week if its full of white/yellow sludge...your head is cracked or your head gasket is bad...either way both have to come off...trust me..been there

 

I'm assuming you mean drive it for a week. And are you saying the hose or the crankcase will be sludge?

 

I hate not knowing 😂 the dr in me wants to be able to accurately diagnose the problem the first time haha.

 

This is what i see under the cap. I haven't noticed coolant loss nor more oil on the dipstick. But this little drop hasn't gone away.

 

You will probably want to consider a UOA from Blackstone. They can confirm if there is coolant in your oil. I think it would be worth the $25-30 to get a solid answer and not risk ruining your engine.

 

+1 . Well worth the money .