Too much oil in the oil filter housing OM642
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Joined: Mar 2005
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97 M3/4
Too much oil in the oil filter housing OM642
During the last 2 oil changes I noticed that my oil filter housing has too much oil in it. When I remove the cap, quite a lot of oil leaks out of the housing making a lot of mess. Any idea what would be causing this?
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
When you remove the cap the the plastic tube in the center of the filter should come with it. Lifting the filter off its seat opens a drain passage back to the oil pan. By the time you finish unscrewing it, all the oil should have drained out. Is the tube not coming off with the cap? Is something blocking the drain passage?
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Joined: Jan 2010
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1997 E300D
The oil filter is part of the oil pressure system and is always totally full, once the engine has been started following a filter change. I suspect that your problem is a timing issue. Try leaving the filter alone until you start draining the pan. After a few minutes getting the oil draining the oil in any galleries higher than the filter top will have drained back into the engine. slowly loosen the filter housing cap and again give it a few minutes to drain before you pull the filter out. I don't know your engine but on my 606 this procedure is nearly drip free.
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
What has been already said.
Plus:
Do you have pudding building up anywhere (sludge)? I like to use an engine flush prior to dumping the oil to clear out any possiblility of sludge. I know it works because the first time I did an oil change (without the flush) it took a quart or two less than the recommended amount to bring the oil level up to full on the dipstick. That's not ok. After using a flush solution, the correct amount per the owner's manual specs brought the oil level to the expected spot on the dipstick.
That said, if your oil is getting sludgy it might be interfering with your filter's ability to drain down properly during a change.
Plus:
Do you have pudding building up anywhere (sludge)? I like to use an engine flush prior to dumping the oil to clear out any possiblility of sludge. I know it works because the first time I did an oil change (without the flush) it took a quart or two less than the recommended amount to bring the oil level up to full on the dipstick. That's not ok. After using a flush solution, the correct amount per the owner's manual specs brought the oil level to the expected spot on the dipstick.
That said, if your oil is getting sludgy it might be interfering with your filter's ability to drain down properly during a change.
Thread Starter
Junior Member
Joined: Mar 2005
Posts: 36
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97 M3/4
When you remove the cap the the plastic tube in the center of the filter should come with it. Lifting the filter off its seat opens a drain passage back to the oil pan. By the time you finish unscrewing it, all the oil should have drained out. Is the tube not coming off with the cap? Is something blocking the drain passage?
What's interesting is that the first oil change I did after the AEM, dealer did not put the seal on the end of the plastic tube that goes into the drain plug. However, some time after the AEM I had the entire oil filter housing replaced by an independent mechanic. It was replaced with a genuine Mercedes part, but now I'm thinking maybe the seal was not placed correctly. I will check my records when the oil filter housing was done. It might as well been two oil changes ago when I started noticing the issue.
The oil filter is part of the oil pressure system and is always totally full, once the engine has been started following a filter change. I suspect that your problem is a timing issue. Try leaving the filter alone until you start draining the pan. After a few minutes getting the oil draining the oil in any galleries higher than the filter top will have drained back into the engine. slowly loosen the filter housing cap and again give it a few minutes to drain before you pull the filter out. I don't know your engine but on my 606 this procedure is nearly drip free.
What has been already said.
Plus:
Do you have pudding building up anywhere (sludge)? I like to use an engine flush prior to dumping the oil to clear out any possiblility of sludge. I know it works because the first time I did an oil change (without the flush) it took a quart or two less than the recommended amount to bring the oil level up to full on the dipstick. That's not ok. After using a flush solution, the correct amount per the owner's manual specs brought the oil level to the expected spot on the dipstick.
That said, if your oil is getting sludgy it might be interfering with your filter's ability to drain down properly during a change.
Plus:
Do you have pudding building up anywhere (sludge)? I like to use an engine flush prior to dumping the oil to clear out any possiblility of sludge. I know it works because the first time I did an oil change (without the flush) it took a quart or two less than the recommended amount to bring the oil level up to full on the dipstick. That's not ok. After using a flush solution, the correct amount per the owner's manual specs brought the oil level to the expected spot on the dipstick.
That said, if your oil is getting sludgy it might be interfering with your filter's ability to drain down properly during a change.
I will check when I did my oil filter housing and see if it coincides with the issue.
Thank you for all your suggestions.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Maybe the oil drain hole is packed with misplaced o-rings...
The "seal" is just an o-ring on the tip of the plastic tube. There should be a new one along with the o-ring for the cap, in with the new filter. Running the engine without that o-ring could reduce oil delivery to the critical parts of the engine.
Yours wouldn't be the first engine where someone dropped something down the drain hole.
Wait, you said "dealer did not put the seal on the end of the plastic tube." Maybe they did, but for whatever reason, it didn't come back out. It might be worthwhile to probe the hole with a hook and see if you can pull something out. The oil should drain out of the housing almost as fast as you can pour new oil from a bottle, faster if it's warm.
The "seal" is just an o-ring on the tip of the plastic tube. There should be a new one along with the o-ring for the cap, in with the new filter. Running the engine without that o-ring could reduce oil delivery to the critical parts of the engine.
Yours wouldn't be the first engine where someone dropped something down the drain hole.
Wait, you said "dealer did not put the seal on the end of the plastic tube." Maybe they did, but for whatever reason, it didn't come back out. It might be worthwhile to probe the hole with a hook and see if you can pull something out. The oil should drain out of the housing almost as fast as you can pour new oil from a bottle, faster if it's warm.
