Bad valve stem seals?

[MGregoir]

I just changed the spark plugs on my friends 2000 Chrysler Cirrus with the 2.4 DOHC four cylinder. He had said it was running badly and throwing a CEL, which coincided with a misfire in the number one cylinder.

The plugs out of the number one and three cylinders had a heavy coating of oil. There was some (about a teasopoon of) oil in the tube on the number three cylinder, and the number one plug had no oil in the tube but was still quite wet. The other two plugs showed normal wear.

After changing the plugs it started easy and ran strong, so the oil fouled plug was definitely part of the problem.

Would this indicate valve stem seals going bad in the number one cylinder? Number three is either runoff from the filler or a bad O-ring at the base of the tube.

 

[froggy81500]

there are either a gasket or o ring at the base of each spark plug well sealing them from the valve cover. That would be the first place to start looking. In a pinch, when I had a caravan with that motor, I took a dab of RTV on my finger and lined the seam between the head and valve cover to seal them without removing the cover. Not the cleanest way to do it but it did work for me.

 

[MGregoir]

There was no oil inside the tube of the number one plug, though, I took a screwdriver wrapped in shop towel and swabbed the tube down to the threads, and no oil came back out of the tube at all.

That was the misfiring plug, and I know this engine uses/loses oil but have never figured out where.

 

[StevieC]

Take it for a good long run, shut it down and take the plugs out that had oil on them and see what they look like. If they are wet you have a blow by problem.

 

[mechtech2]

I'm still not convinced that the valve cover gasket is perfect.
Look again closely.
Fresh oil can help oil use. After 2,000 miles, oil can start to blow out where it did not before [at an increased rate, anyway].
Also, a bit thicker oil can help.
But if it's that gasket, dive in and fix it - it's pretty easy.

 

[Gary Allan]

Well, either way, he's got at least one leaking tube that requires service. I forget how they run things up top on the 2.4, but I imagine that it has hydraulic cam followers. That should mean that he can hit air to the cylinder and manage a spring removal for the valve seal. I'm unsure if the KD tool will work with it, but they've probably come up with another trick tool.

 

[froggy81500]

DOHC with hydraulic lifters if I remember correctly.

Our 2.4 actually had an oil leak from the corner of the cylinder head gasket. The corner closest to the brake booster. It was just an oil leak and not coolant and not a cylinder breach. had the head gasket replaced and a few years later it started to leak from the front corner near the timing end. Not sure if 2.4's are noted for valve guide issues or not, never heard of any. There was a Mopar site that had a lot of good info called Allpar. Might be a good thing to check out and ask around there.

 

[StevieC]

Depends on the engine... Some had DOHC some didn't. As for the valve seals/seats this isn't a common problem on these engines...

 

[froggy81500]

Originally Posted By: StevieC
Depends on the engine... Some had DOHC some didn't. As for the valve seals/seats this isn't a common problem on these engines...


Right. depends on the year. I am thinking on the caravan at least, that newer DOHC 2.4 was around the remodeled ones I think 1997. Ours was a 1998 so I know at least that year. The cloud cars, which is what I believe the OP was referring to, a Cirrus I think, should have that DOHC motor.