Need help. Have an oil burning smell after running for 5-10 minutes. I haven't seen any spots on the driveway, so I'm not sure if its hitting the exhaust manifold or what.

I am adding oil between changes, but my mechanic said this was common in these Monteros.

Have any other owners experienced this problem? Is it a common issue?

 

I suspect 100% that your cam bore o-ring seal is leaking, and its dripping right above your exhaust causing a burning oil smell. check it immidiately, its only a quick fix if your handy enough to tackle it and i think its only $5 for both of the o-ring seal at the stealership.

 

Your mechanic is right, here you go.... https://mitsubishiforum.com/forum/mi...o-rings-36127/

 

I too have a 02 Montero Sport Limited with 204,150 miles and I've experienced the burning smell. For some strange reason the valve cover gaskets have failed several times for me. It never drips a single drop of oil no the ground. I just have the mechanic replace the gaskets and clean up the accumulated oil dust buildup and I'm free of the smell.

 

Ditto. I replaced both the cam o-rings, the valve cover gaskets, and cleaned everything up. Still took awhile for the strong smell to go away, and I still have a weak smell that I've given up on. (maybe the lines into the oil filter bracket?).

Very common problem. Also, even with the engine shield off, no leaks on the ground.

 

I also have this exact same problem. But mine started after the local Mits deal changed the timing belt. Is it possible the cam o rings didn't get handled correctly or should have been changed at that time and didn't. OR could it be something else related to that repair work? I had 125K miles on it then and the burning oil has gotten worse. I am now at 145K.

 

If you clean everything really well, it may be easier to find where the leak is originating. Sounds likely that the cam seals are the issue. I haven't heard of the head gaskets being an issue on the Montero, but from the above posts it sounds like perhaps it's a Sport problem.

Did you have the timing belt replaced at a dealership?
If not, you might think about buying your parts online and going with OEM.
When you do the 120k timing belt replacement, replacing the following is recommended (especially if you do any over landing in your rig):

cam seals
timing belt tensioner
timing belt pulleys
crank seal

I also replaced the water pump and thermostat since it was torn apart already.

Good Luck

 

I believe the oil burning, after cam seals and valve cover gaskets, is at the valve stem seals. Ours loses about a quart per 1K miles with no visible smoke and not a drip on the ground. I just poured in a pint of Marvel Mystery Oil and my clattering at idle lifters are silent for once! I'm sure it won't do much for the valve seals but I intend to up to a 20/50w oil and let it burn...

 

I have a 2003 with a similar smell. Since I've owned it, I've had the valve cover seals done and have replaced a cracked exhaust manifold (I hear these are pretty common issues for these SUV's) and the smell was better for a few months. It has started again so I was wondering if the Cam bore o-ring seals are a problem on the 3.8's aswell?

Is it a tough DIY?

Thanks for any advice...

 

I can't speak on the 3.8's, I'm just not sure on that.

I only replaced the passenger side seal, and it was pretty easy. It took a total of 20 min. I did create a secondary seal with RTV sealant around the edge of the part, but I know some people would not recommend this.

As for the Driver's side, I believe there is a sensor in the cam-bore plug so I didn't mess with it. I inspected it closely and it wasn't leaking anyways.

You'll want to do this on a cool engine. It took over 3 hours for my engine block to cool enough to start the project and I still got burned. So, use another car to go get the materials.