Almost lost my engine - learn from my stupid mistake.
 

Last Sunday I decided to repack my front wheel bearings and change the oil in my car. While changing the oil, I noticed the oil filters I purchased at the dealership didn't have the copper or steel washers included. I also noticed they had two rubber o-rings. I just grabbed one of the o-rings and put it on the filter housing cover. It was tighter than usual going on but I didn't pay much attention to it. I finished changing the oil, shut the hood, finished my wheel bearings and took off.

As I was driving down the road later, I couldn't remember whether I had tightened the bolt in the oil pan. I pulled over and sure enough, it was only partially in. I tightened it up there with tools I had in the trunk - disaster averted.

Monday afternoon as I was sitting in rush out traffic, I smelled something (always the first indication of trouble) looked at my gauges and noticed my oil pressure was fluctuating between 1 & 2. I slipped the car into neutral and gave it some diesel to see if the gauge would rise. It did not. I immediately turned the engine off and coasted into the median. I got out and looked at the car and noticed engine oil everywhere! I got back in and called a tow truck - the traffic was too heavy to stand out there and try to figure out what happened.

I had the car towed to a mechanic. The next day I called him and his first words were: "Who changed your oil?" As it turns out, the o-ring I used was too small and oil was gushing out of the top of the oil filter housing. The car had almost no oil in it by the time it got towed to the mechanic. Luckily, the mechanic was able to fill it back up with oil and the car ran fine. It looks like I got REALLY lucky. Who knows how the engine will hold up in the long term but it looks like I shut it down before anything bad happened.

Moral: Never rush through ANY type of job on the car. After changing your oil, always start the car and observe everything to make sure there are no leaks. Had I done this simple step, I would never have had this problem. It turns out Mercedes had put two different size o-rings in the box and I grabbed the wrong one. In a way I am really mad at Mercedes for packaging their oil filters like that but it really was my fault for not taking my time and double checking my work.

Scott

it had
 

a happy ending. :)
Wow what a scare.

This bears repeating.

Man, I'm glad I'm not the only one who does stupid %^@*&**>!!! That was close and I'm glad you saved it. I didn't realize there are two different o-rings.

Thanks----

I don't think you hurt anything, it seems like you caught it in time. We all make mistakes, it's what we learn from them that matters!

What are all the extra washers and such for? I've replaced the o-ring in the filter cover, but where do the copper washers go?

The copper or aluminum washer can be used on the drain plug (not both). I always use the copper one and put the aluminum one in my box of miscellaneous crush ring box. The "small" diameter rubber o-ring goes in the trash can.

The oil filter has several applications, including, I believe, some american tractor engines. Those use a flat gasket, MB uses a large o-ring, not interchangeable.

The supplier puts all the necessary parts of all applications in the box -- for the 603, some cars have a removable center bolt, some do not, so there is an aluminum crunch washer in there for that application. Not needed on the W126. They don't include the small o-rings for the center bolt, though.

Peter

Something similar happened to me . . .
 

while replacing my left side valve cover gasket. I have done it many times and did NOT take the time to make sure that gasket was seated properly. Engine is M119 and on the left side, there's some 'hard-lines' that brush up the valve cover when you're trying to seat it.

As was the case, the gasket literally curled up and I didn't take the time to use a mirror to inspect and make sure it was seated. Simple tightened everything down.

Well, I idled the car in the driveway for about 10 mins or so, the car started to sound 'funny'. I looked inside at the IC and the oil light came on. You should have seen how fast I turned that car off!!!!

Bottom line, I lost over five (5) qts of oil from the back corner leak in less than 10 mins. The 'funny' :) part was that you couldn't see anything wrong just looking into the engine compartment from the front. Actually from the side either!

The pitch of the driveway was down and to the left (from the front of the car) and all of the oil flowed as nicely as you please under the car and out the right rear side. As I came around the car to the back, there was the nicest oil river you could see!! What a mess!!! :mad: Actually, other than the mess, I got off very easy.

But as Scott said, . . check . . . check and then check again.

Old thread but important lesson!

Somebody is having a slow evening........ :D

The Bump machine is churning!

For some reason there are too many mishaps from changing oil. It is probably so simple people take it for granted nothing can go wrong.

Develop a proccedure and stick to it. Otherwise you will do things like installing the new oil with the drain plug out loose or worse.

A quick check of everything with the engine running afterwards is mandatory. Or at least I practice it. Even though the oil change is so simple..

This started one day when something in the back of my mind told me I had not put the plug back in the pan after draining the oil. After I had just started dumping some in.

heh, the good thing about this is, you can always claim "I like to flush the pan residue with clean oil..."

I hate the feeling of driving the car after a job, then trying to remember if I tightened (insert part description) properly.

That's why I double check EVERY part I touched to make sure I covered all the bases.

When I remove parts I also put them in ONE spot, that way I know every part is located there. A sheet of those blue shop towels is enough for me to consider it as "the spot" then when reinstalling, I check all parts on there and clean them prior to. Also gives me a run down of which ones I've covered and which ones I have yet to install.

My mechanic friend is very good at this, he lets me work on the car with him. Sort of double checking each other as well. Once the job is done, it's done. I've never had to go back to him for a job he had to do twice.

Heh! There's an outside chance of fewer mishaps were there breathalyzers on-site, before some commence on their mechanicing. ......just sayin'! :D