I have a 97 Dakota, 2WD, 3.9L. I started it up one day and ran as usual for a few seconds and then shut-down, and would not start afterwards. By that meaning it would turn over but not start. After running down the list of possible reasons I arrived at replacing timing chain and all that comes with that. I got to the point of replacing oil and coolant. I poured coolant through thermostat hole and it never filled. I checked the dip stick and evidently the coolant was leaking into the oil pan; removing the oil plug confirmed this. I removed the timing chain cover, replaced the new gasket, coated the six bolts that penetrate the water jacket with thread sealant and re-installed. I left the oil plug out and poured water in the thermostat hole and eventually water ran out the oil pan again.

When I originally drained oil and water to begin, they both seemed normal. I'm just befuddled to say the least. If any of you have any ideas on this I would be grateful. BTW: the timing was off.

 

Well I pulled the timing cover off with the water-pump, inserted the six screws that penetrate the water jacket, and plugged the water-pump outlet with plumbers putty. I poured water into the thermostat hole and I could see water draining into the oil pan on the driver's side under the engine at the front. When I started the timing chain replacement, I was going to drop the oil pan and went as far as removing the oil pan bolts but then read that I would have to support the engine and remove the motor mounts. Instead I put a gallon of kerosene in the oil pan, took a toilet brush and scrubbed the bottom of the pan, drained, and put the bolts back in.

My question is, what next?

 

Hi J,

Welcome to the forums.

Was the timing chain bad? Are you reusing the old timing chain cover? Water runs through the timing chain cover and it may have a hairline crack.

Can you post some pics of where the water is coming from?

 

Hi Dan I'm Joe. The timing chain was very loose and it was out of timing. I did not realize that this engine did not have a chain tension-er to begin with. I thought it had broken off and dropped in the oil pan. I took the bolts out of the oil pan, but when I learned it didn't come with a tension-er to start with, I just flushed it out and put the bolts back in.

As I have said earlier, there was no coolant in the oil pan when I drained it. I was thinking that maybe the oil pan gasket isn't seated correctly, but I couldn't imagine how water could get in it. Freeze Plug? I doubt I could get a decent pic, but you can see water splashing as it bounces off the oil pan when looking below and just to the right of the crank-shaft (driver's side) with the timing cover removed.

Thanks for the reply.

 

I've been searching for awhile now, and could this possibly be a leaking intake manifold gasket?

 

Here's a note from the factory manual:

CAUTION: If chain cover is replaced for any reason, be sure the oil hole (passenger side of cover) is plugged.

It's something to consider. The oil pan gasket shouldn't have anything to do with water getting in. Yes, a bad intake manifold gasket could but why? Did you remove it?

 

Dan, is the manual referring to the cover itself, or the block behind the cover? I have a Hayne's repair manual, but did not see this mentioned, I have not removed the intake manifold gasket, just trying to think of possible causes.

 

The cover, not the block.

I'm hoping some of the 3.9, 5.2, and 5.9 guys chime in here.

 

Update. I removed the intake manifold. The front gasket was somewhat deteriorated but the side gaskets seemed okay. There was no coolant in engine valley. I then removed the passenger side head and there was no coolant sitting on the pistons.

I used a shop vac to remove dirt from the valley and the sides of the heads and noticed that I pulled coolant from the passenger side coolant ports, but the driver's side was dry. Actually there is no coolant on driver's until you get to the last timing cover bolt that penetrates the water jacket.

I originally thought that I either did something or forgot to do something to cause the leak. Maybe so, but as stated before I left the oil plug out and when I put coolant inside the driver's side water jacket it pours out of the oil pan at about the rate oil does just before it begins to drip.