240D runaway engine - PeachParts Mercedes-Benz Forum

mplafleur · #1 04-30-2004, 08:02 PM

240D has been smoking like a bandit since we got it. Power steering belt wore a hole through one of the oil cooler lines 2 weeks ago. Leaked oil through the temporary patch until I got a new line from Phil (thanks

). Told son to watch oil pressure and level closely for a while. Apparently it was overfilled by quite a bit as he was checking the oil after it was just shut down and it hadn't accumulated at the dipstick yet.

He called today to tell me that the engine ran away (while parked) and smoke going everywhere. The people in the paint store next to him came running out with fire extinguishers and across the street they called the fire department. It ran for about a minute before it shut down. He didn't know it could run at that high rpm. He also didn't think to press the stop lever on the IP or block the air cleaner. But I would have been suprised if he did anyway.

I got there and found the engine 4 quarts over. He also told me that the breather hose came off and oil was spraying all over. I believe that the engine may have been feeding itself from the breather hose and shut down after it came off.

I sucked out 4 quarts of oil and was able to crank the engine. After quite a bit of coaxing, it began to fire. Only one 1 cylinder and with quite a bit of smoke. It finally began to fire and soon was on all four. But I have a rod knock that comes and goes. And the smoke is embarassing.

What to do now? I towed it home. I don't have a garage yet. (I have batter boards and strings up to mark the foundation though) I am quite willing to rebuild it, in the driveway.

It's an '80 240D with manual. Mileage unknown. It shows 111k, but it must have at least 100k more than that. I have about $2000 in this car. Cost plus euro lights, bilsteins in front, clutch slave, timing chain, and starter.

It looks like I'll need at least:

Main bearings
Rings
Timing chain link
Timing chain rail & guide
Rod beaarings
Sleeves
Crank seal - rear
Crank seal - front

That's about $550 plus machining. That assumes I can use standard size bearing and not have to have the crank reground for next over.

kerry · #2 04-30-2004, 08:40 PM

Are you sure it is a rod knock? I've never heard of a rod knock that comes and goes. If a rod bearing is bad, I'd expect the knock to be consistent. How's the oil pressure?

mplafleur · #3 04-30-2004, 09:00 PM

Comes and goes like this...

I didn't run it long. Only twice and less than 30 seconds total. After starting, there is a knock or clatter that is louder than usual, then 5 or 10 seconds later came a WHAM WHAM WHAM. Definite rod knock. I shut it down and did not start it since.

Maybe I'll run it tomorrow. I just don't want to throw a rod. I'm already working on an engine with 2 holes through the block.

leathermang · #4 04-30-2004, 10:25 PM

I have never understood why the manual shut off did not have a cable to the inside of the car... who, in an emergency , is going to have time to pull the hood latch, then the front latch.. then push the off lever....
As the owner of an identical car all I can say is that you will have a new engine in about the most perfect automobile ever produced.... and I assume your son will learn a lot about Mercedes engines by the time this is over... check out the total cost of a new POS ... and figure in the finance charges... and you will still be $15,000 to $20,000 ahead of the game... and still have a car which CAN be fixed... as compared to so many of the new ones....

turbodiesel · #5 04-30-2004, 11:20 PM

If it's firing on all cylinders and doesn't sound *that* bad.. you'd be suprised how long you could drive it in it's current state.

MattLaFleur · #6 05-01-2004, 12:55 PM

I'm the son and the driver of the runaway 240. I was able to pop the hood. (i thought the throtle linkage might have been stuck) When i got it open so much smoke was coming out i couldn't even get to the linkage or see it. about 30 seconds later it started spraying oil and died on its own.

#7 05-01-2004, 01:05 PM

OK guys, do you really think hitting the fuel cutoff lever is going to shut down a runaway engine that is feeding on crankcase oil?

While it sounds like the incident could have been prevented, and it's a bummer to read about an engine being killed prematurely, once they run on something other than fuel, there isn't much that can be done beyond blocking the source of air. Even that is assuming that there isn't enough air in the blowby gases being fed on, to keep combustion going.

mplafleur · #8 05-01-2004, 07:39 PM

No I don't, when this happens, you don't want to sit and analyze the situation. Just act if you can remember what to do. What if it did happen to be an IP problem? Pressing the stop lever may have shut it down. We know now it wasn't the cause. But don't "not" do it and then kick youself later after the engine is toast.

I showed (or reminded) Matt where the shutoff lever was, but I don't think it would have done anything as like I said, I believe the engine was running off of it's own oil. I was telling someone else today the story and I told him that I didn't blame Matt. It's a learning experience. (Though I do make fun of him saying that he killed the car)

I don't know what I would have done. Although we've kicked around the idea of blocking air and cutting injection lines on the forum before after Larry Bible's car ran away on him. It's quite different when you're there with the engine screaming so loud you think it's goning to fly apart and smoke everywhere. You're supposed to put your hand inside and do something. That's quite brave for anyone let a lone a 17 year old. There's so little time to think.

It stopped only because the breather hose came off, and thus the source of the oil supply to the intake.

BTW, I've decided to buy Diesel Don's 300SD (which is who I bought the 240D from) and donate the 240D. If I put more money in her, I'll have to drive it back out of it. I wasn't planning on having her THAT long.

diesel don · #9 05-01-2004, 09:23 PM

Matt & Michael:

What a stinkin bummer! That was such a personality car from the get go.

Thanks for posting and helping us to learn. I never thought about the thing taking oil in as fuel....

I'll hold the SD for you and hope that you like it.

Don

P.E.Haiges · #10 05-02-2004, 12:29 PM

MPL,

Did you figure how so much oil got into the engine? Someon had to put it in. If it was overfilled by Jiffy Lube or an equilivalent or anyone except yourself or family member, you may have a case against them for another engine.

P E H

mplafleur · #11 05-02-2004, 01:50 PM

It was my son. My only guess is that he read it right after shutting off the engine and thought it didn't have any. Then he put in a couple/few quarts because none registered on the stick.

Is it common to have so much in the passages?

P.E.Haiges · #12 05-02-2004, 02:38 PM

MPL,

Its normal for the passages to stay full but I would think it takes a while for the oil to run back from the valve area above the head. But not 4 quarts, maybe one quart and even less if the engine was hot. I always prefer to check my oil level on a cold engine.

Your son had the right idea of checking oil and adding some. You just have to teach him to be a little more patient and check the oil after he as has added some.

P E H

mplafleur · #13 05-02-2004, 07:19 PM

Yeah, that's what my wife said. "At least he was checking the oil and buying more"

An expensive lesson.

Wasuchi · #14 05-02-2004, 08:32 PM

Speaking of checking oil.... mine never shows anything on the dipstick until you wipe it off and then put it back in and recheck, unless of course you add some oil. Don't know why this is but that might have been happening to him when he checked it causing him to think it was really low on oil.

MattLaFleur · #15 05-02-2004, 09:11 PM

the dipstick showed no at all.