HELP! Engine noisy after oil change and flush W245 B170

[johnny wright]

Hi everyone,

recently we had an oil change to our car and our mechanic friend noticed a build up of sludge at the oil filler cap and he recommended we do an engine flush, so we left the car with him and he done the flush and oil and filter change. Picked the car up and off we went. The next day it sounded like noisy tappets on idle however the noise goes away when driving above 1500rpm went back to see him and he was away on holiday so his colleague advised do another flush as there maybe excess sludge in the sump, so left it with him and got another flush, filter and oil change, however car still sounds the same, he advised we go to merc dealer to check it out. (he didn't charge us for 2nd oil change only the flush £10)

The best way I can describe the noise is like and chain rattle or tappet noise which is more apparent with the oil cap off, its as if there is low oil pressure or no oil getting to the top half of the engine however when the car is revved the noise goes away

one Indy says he'd need to start stripping it down and find the fault through a process of elimination, maybe the tube that sucks oil up is block or the oil pump, however he couldn't give me a cost and i didn't want to risk it running into mega bucks

have any of you experienced this??? any suggestions? should i do another flush and oil change or even a couple of flushes??

not using the car just now as we don't want to make matters worse however can't afford to just have the car parked in the drive

We are based in Glasgow and any help/info would be appreciated

 

[roastbeef]

I have known of people putting a flush chemical in to engines and ended up with what you are experiencing , I think what happens is you dislodge deposits of sludge and carbon witch then block oil ways or hydraulic tappets. I think all you can do is buy a cheap engine oil and change it every 100 miles or less 3 or 4 times I would not put any more flush in to it and give it a good blast up the motor way so hopefully the higher oil pressure dislodges any crap that shouldn't be there or its engine strip and clean

 

[johnny wright]

yeah I agree something has more and likely been dislodged with the flush and blocked somewhere along the line, we have the oil changed at every mot however this is the first we have had a flush.

I'll keep you posted

thanks

 

[ALFIEBEARD]

+ 1

Alfie

 

[ALFIEBEARD]

Never been keen on Flushing engines as some engines have the cams which are in an oil bath and the flushing oil stays in the bath and can cause premature cam wear, also dislodging sludge is not a good thing as it travels around the galleries and can block Hydraulic tappets etc.

Alfie.

 

[grober]

What's the mileage on the engine? I wonder if the timing chain tensioner was blocked by the oil flush and is no longer tensioning the chain correctly? --- its a M266.940 engine TIMING CHAIN KIT Merc A-Class [M266.940 Engine] OE Quality TCK161 [31060] | eBay

 

[johnny wright]

Hi sorry for no replies for a long time, the car has been parked in the drive as we bought another Mercedes. We actually took the car for an mot and it passed, weird however the car runs and drives just noisy. The mileage is 99k we have had the car a long time and are now going to cut our losses and sell as spares/repairs, so sorry to see it go however time, work, kids clubs etc etc leaves us no choice would hate to see it sitting there for years and getting scrapped.......

I do think its a blockage somewhere as one day fine, next day noisy. The tensioner blockage does sound accurate as the noise is like a slack chain.

Good car for someone who has a little knowledge and time