Mmr1

Is it normal for the engine oil filter assembly that is on top of the motor to drain empty after about 45 minutes. I thought an antidrainback valve would prevent this. Does this draining of the filter unit mean lack of lubrication or oil pressure upon startup for a few seconds? I get more engine noise for about 4 seconds on startup.

timballina

Hi just reading about your problem with oil running back. I'm not 100% sure on your model but I've had the same problem on many makes and models of cars over the years and it can be as simple as the 'O' ring seals needing replacing. If the seals are perished this can cause the oil to drain back into the sump and will cause a lack of pressure and excessive noise for a few seconds as the filter gets enough oil pressure. Unfortunately a lot of mechanics don't change all the seals when carrying out a filter change ! Hope this is helpful. Tim. Motor Mechanic

Mmr1

I agree , the mechanic may not have replaced the seals on last oil change. That is obviously the first thing to do. If it continues after seals are replaced, then what could it be?

Russell Ormerod

What engine are u talking about. Usually the oil runs back within seconds.

Mmr1

Do you mean it empties within seconds or refills. It shouldn't be emptying out. I don't know what motor it is, how do I find out? It's A 2013 glk 350 4matic.

Russell Ormerod

272 engine. Well all the thousands of mercedes cars I have serviced when you unscrew the lid the housing is always empty the filter is never submerged in oil.

ItalianJoe1

No if the o-rings are in good shape the filter should have oil around it. Once you release the filter and pull it up enough, the oil can drain past the o-rings and the housing will empty.

Check the small o-rings on the center of the filter cap. If they're hard/flattened out, replace them. A quality replacement filter should bring all of them, the big one for the cap and the smaller internal ones. Cheap filters only supply the larger o-ring from what I've seen.

Russell Ormerod

I always replace all the o rings. What I am saying is once I lift the lid the oil is gone. I cannot say if there is oil in there when the lid is closed. So I presume Mmr1 is asking whether the oil should be there when the lid is off? Where the seals don't matter. In my experience once the lid is lifted the oil is gone.

ItalianJoe1

Right, the only thing keeping the filter full is those o-ring seals and whatever check valve, once you unscrew the filter you allow everything to drain down. Much less messy that way too, if the canister stayed full, it would really launch oil everywhere when you pulled out the filter.

Russell Ormerod

Agreed. I have seen on 111 engines where the oil does not drain back. Usually when the engines have a lot of sludge build up. And yes u make a big mess when u remove the filter

Rocman8

what is your issue? rattle noise on cold start? you have an m276 engine not an m272. if you have a cold start rattle then you need the updated chain tensioners and check valves installed in the cylinder heads. under warranty?

Mmr1

Yes it makes a louder noise on cold start , and after its sat for an hour, just for maybe 4 seconds. And continual louder top end noise in the rear, but I guess that's just Direct Injection. Its under warranty, and extended warranty, newly purchased used "certified" 40000 miles. Dealer says its normal. I don't agree.

Rocman8

It's not normal. There is a bulletin about it. Here's a link that has the bulletin copy and pasted. I've done this repair numerous times and it 100% works and there is 100% a problem with your car if it rattles for a few seconds on startup. If your dealer says normal find a new one or tell them to keep the car and start it in the morning.
http://www.benzworld.org/forums/x204...old-start.html

Mmr1

Ok thanks, they kept it a week. First they overfilled the oil about 1/4-1/2 a quart, it went over the red plastic up to on the wire. I told them, they didn't care. They said they recorded the sound and found it normal. I think I'll record it and try to post a link here. I still think it's strange or abnormal that my oil level continues to rise for an hour, and the oil filter housing is drained dry. Is it possible the noise is lack of lubrication from an empty filter housing, taking time to fill? I don't know the lubrication path so I don't know. I'll look into the buliten. Yes I'm taking it in and leaving it once I get my facts straight.