300m oil changes and burnt oil smell

My wife has a 2000 3ooM. I bought it new for her in April 2000. Car has 23,000 miles. Always garaged. Just replaced the factory tires due to age, not wear. I change the oil. I use Mobil 1. There is nothing challenging about changing the filter or draining the oil on this car. I might drip a little on cross members under the engine but nothing on the exhaust system, unless the shop you use is sloppy pouring oil into the top of the engine.

Do you check your fluid levels weekly? Perhaps something is leaking or has been overfilled and overflows onto hot surfaces during extended road trips?

Steve

I suspect oil is being spilled on you engine when it is refilled. A funnel is necessary to fill this engine to avoid spilling oil on it.

My '04 300M with 73k kms (45k miles) gets a long trip average of about 8 L/100 (35 mpg Imp, 29 mpg US) at 110 kph (70mph). Only 8.3 L/100 on Oregon's ethanol polluted fuel.

Almost certainly that is the problem. I change my own, and the couple of times I did spill a little bit, it has smelled for a while. On that engine, if you do spill any while filling, it is guaranteed to end up directly on the exhaust.

At this particular Chrysler dealership (and I suspect it's the same at many others) their oil-change bay is equipped with some sort of over-head oil hose that is operated by a hand-lever at the end of the hose (looks very similar to the air line that a gas station would have when you need to add more air to your tires). They just remove the oil cap and stick this hose into the opening and squeeze the trigger. There might be some sort of metering mechanism at the other end that insures a certain quantity of oil gets pumped.

They don't open individual quarts or even a gallon container of oil and pour it in - it always just comes pumped in from an overhead hose.

I'm assuming that on my Canadian 300m, that when I switch between measurement units, that what I see are metric and US, not metric and UK/imperial. It's too bad that the metric display of fuel usage does not show at least 1 decimal place - I only see 1 digit for metric display (ie 7 L/100km or 8 L/100 km). And I have no idea if it switches from 7 to 8 when the real number is 7.49 or 7.99.

But like I said, getting 29 to 32 mpg (and I'm assuming US gallons) is now fairly typical on flat terrain at 70 mph. In metric units, all I can report is either 7 or 8 L/100km - nothing more precise than that.

And I'm still using the same K&N air filter that I bought about 8+ years ago when I replaced the original factory air filter. I clean and oil the K&N about twice a year. It still looks new.

And I try to have my tires at 36 psi (cold). That probably helps.

So they dribble some oil when removing the hose. I dropped some down the side when adding oil, the smell was bad for a while.

My 2004 CDN 300M shows one decimal point for metric.

I would have thought that any "dribble" from the filler cap opening would have been burned away after 400 miles and 10 hours on the highway.

Interesting. I wonder if that's a function of the electronics in the overhead module, or one of the computers somewhere else in the car. If it's the overhead module, I wonder if I can get the module from a 2004 car from a junk yard and transplant it into my 2000 car. Or maybe there's a way to reprogram my computer/module?

Where is Glen / Maxpower? He seems to have disappeared from this newsgroup.

She obviously doesn't drive much.

By the way, your timing belt is 9+ years old, but has a ridiculously low amount of miles on it.

What would Bill say about changing your timing belt?

Yea, mine is garaged every night.

I was under the impression that exposure to sunlight and ozone is what ages tires, not necessarily the passage of time.

Well, I've changed my front sway bar bushings twice, the outer tierods once, the electric door lock/latch on both rear doors, the front brake pads 2 or 3 times (and rotors once or twice), put in a new set of spark plugs, and changed one defective coil-pack. But for $35 and 1/2 hour of my time waiting for the job to get done, it's not worth the hassle of messing around under the engine and collecting the used oil into a suitable container that I can throw into the garbage without the wife noticing and forcing me to take it to a "proper" oil recycling depot.

I seem to have this burnt-oil smell for a week or two after an oil change, but perhaps only when I have an oil change a few days before a 2 or 4-hour highway trip.

No. I pretty much never check the oil. I maybe checked it once or twice a year for the first 5 years. Maybe I've checked the tranny fluid level 2 or 3 times in 10 years.

I just went and looked at the current oil level. It's about 1/8" above the full mark.

NEVER any leaks under the car. Of any sort of fluid. NEVER.

Well, if it's 1/8" above the full mark right now, then what are the odds that it was way higher than that right after the oil change, to the point it came out of the dipstick tube?

Go to either

or There's a guy there named Ross who posts as Torontofirecaptain who is *the* world's leading expert on the various electronic computers and modules on the the LH cars. He knows what years of what item are compatible with what years of cars - there may be no restrictions on moving the overhead module among the different year vehicles, or maybe there are - but Ross will know.

He also has a DRBIII scan tool and knows if possibly yours can be reprogramed or if you simply need a new console. The consoles are cheap to buy used - under $75. In fact Ross has a side business of selling LH car parts - I've done business with him several times, and he has an impeccable reputation and respect in the LH car community on the various LH enthusiast web sites. Or you can pick one up yourself from a yard if you care to spend the time looking for he right one. But Ross probably has several of what you would need sitting on the shelf.

Here's his latest Buy/Sell/Trade thread - notice that he prefers email instead of PM:

His personal site for selling LH parts: Discuss with him if you want an OTIS or an EVIC - they are two different versions of the overhead console.

Not sure of this on the 300M, but in the past I have owned vehicles that had breather tubes attached to the tranny that would blow fluid out of them as it warmed up if you overfilled the tranny and stomped on the gas. In my case this was a 1985 Ford product. Great smoke screen on the interstate!

There is in fact a TSB on the M and other LH cars for that - fix involves replacing differential level check plug with a fitting that has a vent tube on it. But I doubt this is the problem in this case. I think oil is being spilled on the exhaust - it doesn't take much to create the smell, and, as said before, if you do spill while filling, it is guaranteed to go onto the exhaust.

I know that post was a few weeks ago, but I recently realized why any drops that spill on the exhaust when filling don't burn off quickly: The exhaust in that area is covered by a heat shield - so the oil is actually getting spilled on the heat shield, not the actual pipe - the heat shield gets just hot enough to make it smell like burnt oil, but

*not* hot enough to burn it off quickly, so it takes a few days of driving.

Last time I changed the oil in my 3.2 (same engine as 3.5, just smaller bore), I spilled a few drops (even with a small funnel, these 4 and 5 qt. jugs that all the oil companies have gone to are almost impossible to pour without some dripping). Had to put up with the smell for 3 or 4 days of occasional driving. It finally went away. Next time that happens, I will probably immediately spray a bunch of brake parts cleaner onto the heat shield and have done with it. Or get a larger funnel and try not to spill it.