99 Malibu Coolant in oil

So yeah, at over 170,000 miles, the head gasket finally went. I've been thinking it might happen and was planning on replacing it this winter as a preventative maintenance thing but it didn't last that long.

To make a long story short, I didn't catch it as quickly as I would have liked to and I would estimate that I drove it maybe 45 minutes with coolant in the oil. When I finally realized what the deal was and pulled the dipstick there was a clattering noise coming from the engine while it was idling. I quickly shut it off but I'm not sure how to procede.

Choices:

1. Replace the head gasket and hope it lasts awhile even though I ran it with coolant in the oil.

2. Replace the engine, radiator, heater core, water pump, hoses and anything else that ever had dexacool touch it and not worry about this coming back to haunt me.

I just don't have a feel for how running an engine with coolant in the oil for 45 minutes is going to affect its reliablity. Before this incident I am confident it was a strong engine. It has never used a drop of oil and I've taken care of it with regular oil changes. I was hoping to pull 250,000 out of it before I had to get a new engine. Now I'm not so sure that's a realistic goal. However, I'm still leaning towards just replacing the head gasket and seeing what happens as it's the cheap fix for now.

What would you do? Thanks.

Just Change the half motor gasket set and send the heads to be fix if the rest is ok well, don't change it

How did you determine it's the head gaskets? If its a 3.1 and you haven't overheated it, it may only be the intake manifold gasket leaking coolant in the oil, not the head gasket(s). Many people tear the engine all the way down, only to find the head gaskets were fine. The biggest problem on the GM 3.1 is the junk OEM plastic framed intake gaskets split at the coolant transfer passage at the end of the cylinder head. This allows coolant to leak into the lifter galley and get in the oil. Fel-Pro (and GM) now offer a redesigned metal framed gasket that addresses this issue. If your car is a 2.4 liter, then head gasket failure is the most likely cause. I would also suggest changing the water pump, t-stat and oil pump drive o-ring (3.1 only) while you have it torn down. This is NOT an issue with Dex-cool, it's the junk gasket GM used on these engines.

True but in my case it was the head gasket set and well, the heads did over heat

Also they can change what you said but like it says "it better to be safe then sorry".

I would also check the main and connecting rod bearings with plastigage and also check them for lateral wear also. Also check the oil pump and pump pickup strainer.

There are ways to determine if it's a head gasket issue, so why do all the extra work if you don't need to. Changing something for the sake of changing makes no sense.

I would be interested in hearing any suggestions on how to ensure the head gaskets are good so I don't have to tear it completely apart. Like everyone else said though, if that's not possible, I'm not interested in doing this job twice so I'd just assume tear it clear apart.

The car is still sitting where I parked it full of oil/coolant. I haven't even had time to drain it. When I get a chance I'm going to drain it and replace the filter and refill it with oil and see if it's still making the grinding noise when I start it. If it's still grinding I'll try to figure out why and if I get a good idea that it's something serious it's just as likely that I'll put a new engine in it as it is for me to tear it apart and try to fix it.

I appreciate the suggestions on the main and rod bearings and the pump and pickup strainer. If I end up tearing it apart I'll definitely do those things. Thanks.

As far as the overheating is concerned, it has been overheated 3 times that I know of.

The first time was in a traffic jam and an idler pulley locked up burning the belt off. I kept going till it just barely got into the red so I wouldn't be holding traffic up anymore than I had to.

The second time I got it stuck in mud. A female friend did the driving while the rest of us pushed. She didn't pay much attention to the temp guage but I think I caught it before it was any worse than the first time it overheated.

The last time was when the coolant started going into the engine. I was daydreaming and I didn't notice it till the little bell dinged at me and the light went off.

My guess is those three instances are worth checking the head gaskets but I could be wrong.

170,000 miles? I wouldn't fix that engine. probibly is the lower intake manifold gasket...you can tell by the coolent pooling on the to of the transmission. You can if you want too. the replacement process is in the haynes manual...and if the new gasket doesnt work your only out $100

john

170,000 miles? I wouldn't fix that engine.

Thanks for the input. I think that's what I needed to hear. This is my primary personal vehicle. I don't use it often, but when I do use it, it'll be for long trips (2000+ miles) and I don't want to have to worry about it. When the next long trip comes up I'm not going to be comfortable with a $100 dollar fix that may or may not be a long term solution.

There are ways to determine if it's a head gasket issue, so why do all the extra work if you don't need to. Changing something for the sake of changing makes no sense.


Can you tell me specifically how I can tell if its the head gasket or the lower intake manifold gasket? I have a ton of coolant in my oil....but also externally leaking. The intake is damaged for sure, but now my mechanic is saying he thinks the volume of the coolant in the oil points to the head gasket being damaged too........but its double the price to change the head gasket and, according to him, there is now way to tell if the head gasket is bad.

Any info would help! Thanks.

Can you tell me specifically how I can tell if its the head gasket or the lower intake manifold gasket? I have a ton of coolant in my oil....but also externally leaking. The intake is damaged for sure, but now my mechanic is saying he thinks the volume of the coolant in the oil points to the head gasket being damaged too........but its double the price to change the head gasket and, according to him, there is now way to tell if the head gasket is bad.

Any info would help! Thanks.

If its the lower intake manifold you will see a pools of coolent where the transmission meets the engine [right hand top side], and on the opposite side next to the serpintine belt idler assembly.The lower intake manifold is "V" shaped. I don't think I've heard of many head gaskets failing. But EVERY lower intake manifold gasket leaks in the 3.1L by 80000 miles God Damn GM. All they had to do was spend a few bucks ang apply a better gasket
[use FelPro]
If its the head you will see bubbles in the coolent tank when running. You can do a compression test on each cylener. To find a bad head gasket. But youwill have to swing the engine forward to reach the back three. And if your mechanic says there is no way to tell a blown head gasket, find a better mechanic [seroiusly] I don't know how much damage has been done to the berings if you say the crank case is full.. if the oil is like a milkshake...i'd be wary of putting money into it. But I think you head is okay unless you seriiously overheated the car