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Just wondering if any of you have an experience with the oil pump in the E55?
History -
When warm my oil pump chain has been hitting the front casing, i pulled the front cover, replaced the chain and tensioner. There was a tiny amount of stretch in the old chain, the new was noticeably tighter. Put it all back together, still hitting when warm. (there are visible marks on the case).
So i have just pulled the oil pump to inspect and replace the plastic pressure relief valve. The plastic valve looks ok and its spring action is similar to the new one.
The pump looks good, and the gears look new with no visible damage, rotates as it should. However, there is a small piston looking part in the pump towards the backside, you can see if from out side the pump and it is held in with a retaining clip, so it cant out out of the pump. Now I am guessing it is meant to move in and out...I cannot move it with my fingers, is it meant to move? Looks like it should.....anyone got a pump lying around they can try push?
Thanks for any feedback guys, really appreciate it, want to get this annoying chain rattle gone.
The noise is noticeable when the oil has reached operating temperature, not so much when cold to almost non existent. Even with a new chain and tensioner I still have slap, so I have just removed some material from the front casing, hopefully that gives it enough room to not hit.
As for my original question, the pressure valve is working as it should, there is a little hole in the piston where you can lever it open.
oil pressure or temperature has nothing to do how the oil pump chain or tensioner is working. Are you sure your chain isnt too long, where did you get it? could it be the new tensioner thats bad? With new parts it should not touch any where= slap.
All MB parts, when reassembled the tension was way tighter than previously, it is just a poor design, the slack side of the chain is very close to the case, even the slightest movement of the chain will cause contact. As the chain wears a larger groove in the case the sound gets louder as the impact is greater.
The noise is present and noticeable when warm, the chain is probably hitting when cold too. There are a lot of E55's with the same issue, some are more noticeable than others.
Is there possibly a new redesigned oil pump out there for E55's ?; maybe MB-AMG was aware of this issue, back in the day and made improvements to it ? Just saying
All MB parts, when reassembled the tension was way tighter than previously, it is just a poor design, the slack side of the chain is very close to the case, even the slightest movement of the chain will cause contact. As the chain wears a larger groove in the case the sound gets louder as the impact is greater.
The noise is present and noticeable when warm, the chain is probably hitting when cold too. There are a lot of E55's with the same issue, some are more noticeable than others.
One can argue about the design.. fact is that if everything is new, there is no sound. Or its coming from somewhere else. Cant hear or see the car so hard to tell. I sure am aware of how it looks inside
Is there possibly a new redesigned oil pump out there for E55's ?; maybe MB-AMG was aware of this issue, back in the day and made improvements to it ? Just saying
MB has changed the part number of the pump at least once, so maybe the new one is a redesigned pump.
One can argue about the design.. fact is that if everything is new, there is no sound. Or its coming from somewhere else. Cant hear or see the car so hard to tell. I sure am aware of how it looks inside
I took away a lot of the metal that was close to the slack side and will be putting it back together tomorrow and running it up and testing.
You seem pretty competent, I don't know about the pump, but try searching experimental chain tensioner. Might give you some ideas.
Yeah it looks like there are a few people with modified tensioners, if removing some of the casing doesn't work, I will most likely pull the front cover again and attach a chain guide somehow.
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