Well, to start from the beginning so it will make more sense (if thats possible)

I bought this car in December. When I changed the oil, it was EXTREMELY dirty and the filter was very old and had a big (not original) hole in the side of it.

When I took out the filter- the canister was full of oil, which I thought was odd, but now I think I know why it was like that. I never thought much about it. When I changed the oil, I used RotellaT 15W-40 and a NON-MB filter. I put 1000 miles on that oil, then changed it today. Well, when I removed the cover from the filter canister- the canister was EMPTY. I was told by another member of my family that the MB filters have an anti-drainback valve and the others do not. Seems like this could have been the case here? Does anyone know if this is true?

Anyway- I did not think much of it- I changed the oil- put in the Mercedes filter and this time used Castrol GTX 20W-50. Normally, I will remove the coil wire and crank for a few seconds (on my other cars), but was not sure if this should be done on Mercedes, so I did not do it. Mistake? When I started the car- it ran for about a half of a second, then stalled. I thought, "OH NO" - the chain or tensioner broke"! So, I hesitantly turned the ignition again and it started, but with a loud knock and what seemed to be a miss for about 3-4 seconds! I thought for sure something bad had occured, but then it quickly stopped and the engine smoothed out nicely as normal. I let my father know and he said I should have either disconnected the coil wire and cranked, OR should have filled up the oil canister with oil before I started- which I never thought about doing, or even know if that should be done.

Anyway, is it possible that I damaged my engine, or drastically shortened its "life"? I really need this car to last me for at least another year, so I hope I did not cause damage by not filling the canister before I started.

Any info about this, or the drainback valves appreciated.

BTW - the car is a 3.8L V8.

I do not think and I hope you didnt do any damage??? Was your car on ramps when you chaged the oil? Sometims the elevation of the car pushes the oil toward the back of the oil pan and when you go start it, oil doesnt get to the engine quick enough because of the slant.

When I do my oil changes, I use ramps. But I do not add oil then crank and add more oil. I just add the correct amount, check level and start. Let it run and then take it down the ramps. I also do not use OEM oil filters. I just use the ones I can find at pep boys or auto zone. The OEM filter does look different from the aftermarket ones though. I have never had a problem with aftermarket filters. On occasion, I heard a slight rattle or faint knock but goes away instantly. I beleve that noise if from the valves and or some metal to metal parts in my engine. Now that loud knock of yours doesnt seem to sound too good from how I am imagining it but have the car checked out anyway just to be safe. The oil I have been always using was the 15-40 rotella which is a great oil. I had my mech open my valave covers to change the gaskets in the 560sel I have and he was impressed that the engine was sparkling clean, and thats with 151k miles!

__________________
2001 E55

2001 E320 Sedan

2001 Subaru Legacy

2006 SLK280

2016 Subaru Outback 3.6

You said you ran it with the coil wire off for a couple seconds.

Make sure you crank the car over while watching the oil pressure gauge.

Sometimes it takes maybe thirty seconds or so to build proper oil pressure up.

You may run the battery down doing so, but don't start the car until your oil pressure comes up on the gauge.

The pressure gauge is your friend.

I have ran down plenty of batteries trying to build up the oil pressure after changing the oil on the v-8's.

Thanks for the replies. No, I didn't crank it with the coil wire removed. I wish I had of. I have did this before on other cars, but not on this car. I had never owned a gasoline Mercedes before and was not sure if it should be done- so I did not do it. I was about to though.

Two560: Nope, I didn't have it on ramps, that wasn't necessary, as I could easily gain access to the drain plug. Luckily, the oil pan is far enough forward for this. The car was setting in level ground. I hope no future damage will occur sooner than it would have if this had not of happened. As mentioned- the knocking went away, but I cringe when I think about it doing it, because something was not properly oiled. I hope it did not weaken my chain tensioner.

I honestly think the MB has an anti-drainback valve, which keeps oil in that canister, which is why it was full the last time I changed it - then I used a NON-MB filter- which did allow the oil to drain out- hence the knocking. ??

I have another thread about a "VRRR" sound on frist startup of the day. Now I am almost sure it was not doing this before I changed the oil last time. I think the non-MB filter had something to do with it. I will know the next time I start it for the first time of the day. If no "VRR" or "ZRR" sound- I will know it was the filter that was causing it.

Cranking it with the ignition wire off is a waste of time. On a tight healthy engine the oil pressure comes up within like a second after a change. Even on my 250k+ mile 603 it comes up right away.

I remember when I started my friends S320 right after we did the oil change the guage came up as it was cranking and was at 3 bar right after it caught.

It was probably your tensioner acting up.

__________________
2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

One should never crank an engine with the coil wire disconnected. Many modern electronic ignitions can be damaged if the secondary circuit is open. IIRC the Mercedes service information has a warning about this as many others do. If you want to disable the ignition, disconnect the 12V power to the switching module.

A proper Mercedes oil filter has both an anti-drain back valve and the bypass valve. Only buy a proper Mercedes spec oil filter like the Bosch 72165 from a reputable Mercedes parts specialist. Many McParts oil filters including "Bosch" brand that Autozone carries do not meet the OE spec even if their catalog calls out a number.

After an oil change, start the engine and hold about 1000-1200 revs. The oil pressure should rise within about three seconds.

A ticking sound on statup may be due to lifter bleed-down or a "sticky" lifter. If you believe the internals are dirty and may have some lifter clogging I suggest you continue to use CI-4 oil.

Duke

The tensioner knocking?

When you say yours "instantly" gained pressure- is that when your filter canister is full of oil? I am assuming that you are using MB filters. Remember, my canister was empty - there was a cheap filter in there.

As mentioned above- there is probably not even anything wrong with the tensioner and it was probably the off-brand filter causing that. Also- this AM (before oil change), I had someone listen when I started it- that noise sounded like it came from the PS pump area.

Well, if I knew for sure that the MB filter had an "anti-drainback" valve, it would make a little more sense. When I first start it of the morning, the pressure goes to "3" within a second and as mentioned before, when I changed the oil the last time, the filter canister did not drain out the oil and it did not make any noise when I restarted then, but that is when it had the old MB filter I removed and replaced with the cheap one that I removed this evening- when that canister was empty. I am anxious to see if that first startup still has that "VVRRR / ZZRRR" noise until pressure reaches "3".

I am just wondering why the canister was empty this time (with the off-brand filter) and before it was full (with the MB filter). Thats why I am thinking it is true that they are indeed anti-drainback filters- because it was holding the oil in.

My car does have 265K and it probably was not as meticulously maintained as yours. The first 200K was put on by the original owner and was well cared for it appears, but the guy I bought it from had put around 64K on it and he did little to it. I do not think he changed the oil more than a few times. He even told me all he did to it over the 5 years he owned it was change the fuel pump.

Duke- that is what I was concerned about. It is really not a problem on the older cars (to disconnect the coil and crank), but as mentioned, I was unsure about the MB, so I did not do it.

As someone above mentioned- "it is a waste of time", some would not agree. I know of a lot of people that do this. It may not help much, but it does lessen the "dry start" a little. Not all engines are "tight and healthy".

Thanks again.

I'm with that opinion - and also, how important it is to fill the oil filter before reinstalling. It's pretty disturbing that the canister was empty when removed. That just isn't normal. Is it possible that it wasn't installed properly? There are some parts (spring, a washer, for the bypass) that come off, and the order is important. You mentioned that the filter had a hold in the side of it. Do you think that someone might have done this deliberately because the bypass wasn't working?

__________________
86 560SL
With homebrew first gear start!
85 380SL
Daily Driver Project

http://juliepalooza.8m.com/sl/mercedes.htm