Found something in oil change

[560slsteve]

Today i changed oil in the 560-1987 with 149k miles. in the oil pan after dumping the filter, i found pieces of a black plastic part that looks like a plastic bushing of some kind with a lip on it. it appeared to be about 1/2 inch in diameter or slightly less, judging from the half piece i found of it. the length of it might be 1/2" long or so.

I am not sure if this came from the sump or the oil filter, but i noticed it after dumping the filter canister.

the car is running fine at speed, plenty of power and acceleration. i have been putting more road mileage on it lately as i travel out of town more often and love to drive it. it does miss at idle, a common problem i have found on this forum and one that i have been chasing gradually. I have replaced the injectors and holders, seals,,etc; new plug wires, etc. the usual as everyone does on this forum. i have also cheked all the vacuum lines with a hand pump and have determined that the thermovac valves are working and no vacuum leaks that i have found. I have also sprayed the intake manifold with carb cleaner and can find no changes. i changed fuel filter and am down to having the fuel distributor rebuilt, which is my last hope i guess. it does surge sometimes on coasting downhill at speed. AND i also checked compression on each cylinder, and they were all near 135.

Now i have found this plastic piece in the oil, and was wondering if anyone here knows what this could be. i dont know if the timing chain has ever been replaced, or if any plastic part possibly from there can get to the sump, but there is no noise up there that i can hear.

I would appreciate any ideas on this, as well as any suggestions of what i might have missed on idle miss.

thanks and happy holidays.

steve

[LUVMBDiesels]

Take a picture!

This could be nothing or something really bad

[Roncallo]

Originally Posted by 560slsteve

Today i changed oil in the 560-1987 with 149k miles. in the oil pan after dumping the filter, i found pieces of a black plastic part that looks like a plastic bushing of some kind with a lip on it. it appeared to be about 1/2 inch in diameter or slightly less, judging from the half piece i found of it. the length of it might be 1/2" long or so.

I am not sure if this came from the sump or the oil filter, but i noticed it after dumping the filter canister.

the car is running fine at speed, plenty of power and acceleration. i have been putting more road mileage on it lately as i travel out of town more often and love to drive it. it does miss at idle, a common problem i have found on this forum and one that i have been chasing gradually. I have replaced the injectors and holders, seals,,etc; new plug wires, etc. the usual as everyone does on this forum. i have also cheked all the vacuum lines with a hand pump and have determined that the thermovac valves are working and no vacuum leaks that i have found. I have also sprayed the intake manifold with carb cleaner and can find no changes. i changed fuel filter and am down to having the fuel distributor rebuilt, which is my last hope i guess. it does surge sometimes on coasting downhill at speed. AND i also checked compression on each cylinder, and they were all near 135.

Now i have found this plastic piece in the oil, and was wondering if anyone here knows what this could be. i dont know if the timing chain has ever been replaced, or if any plastic part possibly from there can get to the sump, but there is no noise up there that i can hear.

I would appreciate any ideas on this, as well as any suggestions of what i might have missed on idle miss.

thanks and happy holidays.

steve

Do you still have your old oil filter there should be a rubber grommet at each end.

John Roncallo

[rocky raccoon]

The lower chain guide is made of a material and cross section similar to that which you describe.

When changing the timing chain, it is common and prudent to change the tensioner and upper chain guides sometimes the oiler also. The lower chain guide is often left unchanged for the following reasons; (1) Conventional wisdom believes that the lower guide wears at a much slower rate than the upper guide and (2) The cost of a chain job can double if the lower guides are replaced.

At 175k miles, you are seriously past due for chain service if it has never been done and/or approaching time for a second service if it has been done. Conventional wisdom again says about 90k miles between chain services for a stress-free driving experience.

My opinion is that it is time to get into the chain case. If you want to check further before committing, buy a lower chain guide (they are inexpensive) and compare it to your fragment to see if they match up. You could also take the fragment to an experienced, trusted mechanic. They should be able to identify it. I hope you still have it.

[Walrus]

I'm a bit confused... I am assuming the oil pan you dumped is a drain pan, and you found the piece when you dumped the oil canister into your drain pan? Hmmm... Seems I recall there is not room for a piece as big as you describe to get from the timing case to the oil pan, to the oil filter housing.

I have to admit; my first impression was timing chain guide... I can't see how a piece of guide could make it to the filter housing...

Like someone said, post a picture of the offending piece. Several of us can recognize timing chain guides in our sleep!

[560slsteve]

thanks for the replies. i did dig into the trash and luckily found this piece. it appears to be the same inside diameter as a filter grommet, but the lip on it is a different size. its feels like hard plastic, but it smears on your hand like rubber. maybe its an old grommet that has been in there for a while and hardened. there were about 3 other pieces, but they are small bits. so i figure the rest of this is somewhere.

i also pryed out the filter grommet for comparison. I finally figured out how to degrade my camera enuf to send these photos, and they should help to see if this could be part of timing components. i cant figure any other plastic parts like this in the engine, but i havent been into the engine YET!! seems like i have been every place else, and i figure i cant be as bad as the evaporator replacement, whatever this turns out to be. i can never sell this car, because i feel i know too much about it now!!

thanks for all the replies.

[560slsteve]

after reinspecting the old oil filter, i think this piece came out of the sump rather than the oil filter cannister. this is because i didnt notice any particles onthe outside of the old oil filter, or inside of the canister when i was wiping it clean.

i drained the sump and let it stay open for 10 minutes, crawled back under and screwed in the plug, then slid the oil drain pan under the filter, and then removed the filter housing. i really didnt notice this thing until after i had dumped the filter, and pulled the pan out to let the filter element drain. when i saw this piece, i checked the filter grommets and cleaned up around the filter bracket on the engine and stuck my finger in the holes to see if i could feel any other parts. it was all clean. so if i had to bet on it, i would say it came out of the oil pan when it first poured out.

someone give me some good news and say its 100% not out of the timing stuff!!!!ha

[meltedpanda]

is this soft or hard material,?

[560slsteve]

this material is hard, but its not brittle feeling like regular hard plastic. now that its dry, i can write with it on a piece of paper. feels like i can scrape material off with my fingernails---but its hard to tell how long it has been immersed in oil.
i dont know if oil-soaked soft plastic with heat and age can turn like this, but i have replaced O-rings on boats that were so brittle they felt like graphite, and their replacements were nice pliable rubber. that was how hard they were from age.

supposed to drive it on the interstate tomorrow for about 3 hours....so we'll see. needless to say, the radio will be off and i will be listening!!!

[rocky raccoon]

I guess you are on the road now Steve. Good luck! None of us asked if you had the classic "clatter on start up" symptom. If you do (did) I would suggest using another of your vehicles for this trip.

"Denial is the Enemy of Reliability". (Just made that up but I like the sound of it).

[560slsteve]

hey rocky,

getting ready to get underway in a few minutes and thought i would check in. no clatter or anything on startup----the car starts rights up, warms up geat, and then when warm at idle starts that missing crap. i have heard many others on here say they drive it like that without problems, until they get the cause figured out eventually.

i did take the car a while ago to a mercedes mechanic about 100 mies from here, who is a quasi friend. he hooked the car up to that lamba meter, did a slight twist or 2 on the richener screw with the allen wrench intot e top of the air intake, and said the miss was definitely fuel related and not electronic. he was impressive and works in a huge shop that deals with mercedes, and i got hte impression it was not the first time under the hood of one of these cars (although he did say he heard they built the car around the AC evaporator and he hadnt had the pleasure of doing one of those yet, like i have.)

he said the car was lean, and the electronics were trying to richen it, and he couldnt do it with the richening screw. he diagnosed the injectors, or the fuel distributor, and said to do the injectors first (bosch recommends changing them at 100k) and change the fuel filter, plus he claimed that if i also did the fuel distributor i would pick up 25 horsepower. i know that when i break the fuel lines on the FD they all change the idle except #8, which has good compression. the mechanic never mentioned the timing or if i had ever changed the chains.

i havent done the FD yet, thats on the christmas list. and now with this 'find' in the oil, i am thinking about doing the chain and tensioner just to be safe.

thanks for the reply and i will see how it goes today. i am low on cars this holiday, plus i like smoking those rice rockets with the SL on I-40!!! Hope its not an expensive ride.....

[meltedpanda]

I am with the Walrus, I dont see how this could migrate from the chain case to the oil pan. Gotta be from something close by .
You don't suppose this could have been in the drain pan prior to drain....been there done that.
In any repspect - good luck on the trip and Merry Christmas. Perhaps Santa will give you a new SL

[560slsteve]

well, just made it to the piedmont of NC from the coast after 3.5 hours at 80mph on I-40. no problems, car ran well. maybe that thing is an old oil filter grommet from years past, before i got the car, and has been floating around in the oil pan for years. i listen carefully when it starts to hear any chain noise fromthe engine, but all sounds good up there.

i have one of those flat type oil drain pans, and i keep it clean and wiped before i change oil, just to see if any debris come out. so i know it wasnt in the pan beforehand.

this is a great car and loves to be driven, even though it is trying at times. but thats the challenge, and i will eventually get that idle deal worked out, and it will feel so good when i do. it runs so smooth at speed.

thanks for the respnses and happy holidays. i have to get out there and scrape a couple lexis's out of the grill............

[meltedpanda]

glad you made it, I was wondering, gotta love the ol Benzes they are much fun to drive and tinker on, in fact it is so warm here today I am going to get the cover off my 450 and take her out for a spin, we have had enough rain to wash all the salt away
Merry Christams all

[rocky raccoon]

Steve:
I am so pleased that you made it w/o problems that I am ready to make a suggestion regarding your idle problem. My 1988 560SL was delivered to me with a similar problem only much more severe than what you describe. The car started and ran o.k. until fully warmed then became almost undriveable.
Logically, the problem is temperature related and comes on when the engine is at normal operating temperature. It also appears fuel related rather than ignition. Using that logic and ALLDATADIY, I was able to isolate the fault instead of just throwing parts at it which can be a very expensive proposition.
In my case, the problem was a faulty engine temperature sensor, the one that sends engine temp to the fuel injection computer. That sensor is located on the driver side intake manifold toward the front of the engine under the front edge of the air cleaner housing. It has a green base and two wires coming out of the top. You need to remove the air cleaner housing to gain access. I would do a voltage and resistance check at that sensor to see if it operates properly when the engine heats up. I reported that repair in this forum about a month ago.
The disclaimers are: In my case, the fuel injection system was going to full rich instead of lean. That was evidenced by the odor coming from the cat convertor and spark plug color. My recommendation is to check all the cheap stuff like this first before getting into expensive replacements like a fuel distributor.
I also can strongly recommend subscribing to ALLDATADIY. It is one of the best $25.00 I have ever spent and has paid for itself many times over. This engine temperature issue was the first time I used it and I have used it many times since then. It gave me a lot more confidence in maintaining this car myself to a large extent.