Jud Chapin

Changing the oil on my CPO '16 S coupe (first time since purchase its been changed) with suction method only removed 6 qts of oil. I checked the oil level before the change and the dip stick showed min. Then upon refilling, it only took 7 1/2 qts. vs. the 8 1/2 it calls for to get to the max. level on the stick. Anyone have similar experiecnces.

Katie22

YEs YES YES. My Maybach and my AMG GTC are both 1 quart less than what it calls for. I leaned this the hard way and had to suck out 1qt oil from each.

PS the same results are reached if you drain the pan from the bottom with the drain plug. You still have to add one quart less than what it calls for.

Jud Chapin

Thanks...I was first wondering if the extractor (Holt Industries #62643) was getting all the old oil out or if MB mechanic who did the CPO oil change shorted me on what he put in as only 6 qts came out.

Anyway, not impressed with this extraction method (my first) as it took over an hour and a lot of pumping to get the 6 qts out. Think I'll go underneath next time. What do you think, Katie?

MacMP

I use a similar extraction pump. Takes less than 5 minutes.

Jud Chapin

How much time actually pumping? Mine seems to stop pumping after about a minute or so.

superpop

I have one that attaches to my compressor and I do not do any pumping. Might want to go that route.

Jud Chapin

Who's the manufactuirer and do you have the model #.

Nice Ride

Did you start the car after adding the oil to fill the filter, then turn off and let the car sit for at least 10 to 15 minutes to get a accurate reading? Oil is still draining back into the sump way after you turn off the engine. Not a full quart, but a noticeable amount...

Katie22

Jud I have that exact pump and it works great. You will have better luck if you start the engine and heat up the oil before you extract it. I did change the oil on my Smart car and did not heat up the oil and it did take 20 min to suck out 4 quarts so yes you have to heat up the oil.

Katie

Jud Chapin

Yes I did. Been changing oil on my cars for 60+ years so I guess I 'm no rookie.(lol) Thanks...

chassis

I don’t believe in top side extraction, based on comments across many automotive enthusiasts sites. It’s an extended pain in the rear, and questions of effectiveness never go away.

My MB dealer bottom drains the oil in my GLE, when WIS indicates a top extraction procedure. The dealer ignores MB in this case.

The new MB straight six engine specifies bottom drain.

For me it’s bottom drain, done either by me, or by the dealer.

Jud Chapin

Thanks, Katie. I did run the engine for about 10 minutes before starting. While the pump is new, first time I've used it, it must have a leak. The suction action only lasts for a minute or so and then 10 or more pumps to get it going again. Not sure if this is normal or not. I did tighten all the screws on top. One thing I did notice is the dip stick hose portion goes into the hose adaptor for the larger hose very, seemingly too, easily. Guess I'll have to test the hose connections and all else for leaks.

Jud

Jud Chapin

While I'm no engineer, I've read where the suction method actually does a better job removing old oil.

chassis

@Jud Chapin Hello Jud Chapin. I am an engineer, and there is no way the top extraction is more effective than bottom drain. It’s physically not possible. Add to this, operator difficulty with consumer-grade extraction pumps, and there can be no comparison that bottom drain using gravity is the solution.

Top extraction in my view is an increasingly abandoned way to try to save time in the service bay. If it clearly saves time and money, money grubbers, pardon - dealers, would be doing top extraction without exception.

If dealers, who we all know are keenly financially oriented, are disobeying M-B’s written WIS instructions, top extraction cannot be seen as necessary, faster than, or better than, bottom drain.

The downside with bottom drain for the DIY consumer is the vehicle needs to be raised and the consumer needs to crawl under the vehicle. On the other hand, dealers have lifts and/or pits, dealer technicians are generally younger and more physically able, and other service work is easily accomplished when the vehicle is on the lift.

superpop

I use the Mityvac MV7300* PneumatiVac that hooks to my compressor. Do all my cars this way and I have a lift if I wanted to do it from the bottom. Have to disagree with you chassis on this. I did not believe that the fluid extractors would work as good as good old gravity but they do. When I first got mine I drained the fluid with the vac and then popped the drain plug on the pan just to see. Nothing came out, so I have to assume both methods effectively remove the oil from the motor to the same degree. Topside is just so much easier and cleaner, especially when the filter is topside as well. I run my car for about 5 minutes to warm up the oil, not get it hot but just warm, then suck it out, takes about 10 minutes on the compressor.

jl199986

Often times the design of the oil pan is such that the material around the plug itself is raised just a bit compared to the rest of the floor of the pan. (tbh not sure on the S myself though) Clearly some engineer(s) must have considered this, but it seems like competing concerns around the plug sticking out too far or other things I haven't considered leave this design. The result is a bit of oil left in the pan even with the plug open. I guess not enough to be deemed a problem vs the design. This is where the extractors seem to work just as well.

I've had same experience with my Golf's. Top extraction leaves nothing to drain through the plug if opened. Despite what the physics indeed would suggest.

Also I handpumped my Mityvac, and it too only took 5 min or less. Gotta repump to get keep the vaccum strong a couple times, but no big deal.

Nice Ride

Need you to explain this one. It is impossible to hit the bottom of the pan at the lowest point and drain all the oil. Now I want to be fair, my OCD makes me do the following....
I always do the following.... Its just me,,,
1. Drive up on 4 Jack Stands, this raises the car just perfect for getting underneath and having the car level.
2. I add about 1/2 a can of SeaFoam, let the engine idle for 15 min. while I get everything ready for the Drain, Filter and Fill. The SeaFoam or other, allows the Varnish / Tiny Oil Valleys to get nice and clean.
3. Shut the car, drain till I see Dripping oil, not flowing. It takes a while for all the oil to drain out of the valleys etc. While draining, I change the Filter.
4. After I install the filter, I add a few ounces of oil, once I see the flow, I put the plug back.
5. Fill 1 Quart Short to start, 8 Quarts, Start Engine Run 1 Min., Stop Engine wait a few, Check Dip Stick and add Oil till at top of Mark on Stick. For a 2014 S550 W222 4Matic, it takes a total of 9 Quarts.
6. Scoot around under there checking for leaks.... Done.

Nice Ride

One thing to be VERY CAREFUL WITH.... If you Raise the Car ( Height Button) and scoot under there, the car WILL lower after a period of time on its own with you under there....( I think after 15 min. mine will lower on its own) If you are on a creeper, you can get caught / Die if your not careful....

Jud Chapin

Nice Ride, not sure why or what you are asking me to explain. I simply said I've read that the suction method does a better job. If you Google the subject, which I did today since I'm new to this method, you'll find many opinions as to which is better.

FWIW, I'm 78 and have been changing oil on my cars at about the 4-5k mile mark for over 60 years, all of which have been done by removing the drain plug except for this last time when the suction method was used. So at this point, I really don't have an opinion as to the better method. But one thing I will mention is that having your car level does not necessarily mean you will remove the most amount of oil. I had a '76 Vette a while back and was able to change the oil from below without having to raise the car. After I had done a drain with all 4 tires on the ground, I would jack the car up slightly on the driver side. This would always result in additional oil being drained, perhaps 1/4 to 1/2 qt. (Actually I don't recall just how I discovered this). Anyway, just my 2 cents.

Katie22

I failed to mention that I suspect the factory oil capacity is incorrect is because there is oil in the oil coolers and if the oil is not hot enough for the thermostats for the oil coolers to open. On my GTC the oil change directions require you to get oil temp to 212 degrees and then within three min drain the oil out of the tank. Even doing this I still have to put in one less quart in that car than it calls for.

As far as sucking the oil out vs draining. I think with new synthetic oil you dont have sludge and garbage at the bottom of the pan like you did with dino oil so sucking it out is not a problem. Now with dino oil yea drain it out of the bottom.

Jud Chapin

Well that would explain it. The WIS for the C217 and W222 says warm up engine and get coolant temp to 80C or 176F. I imagine the oil is pretty hot by the time the coolant reaches 176. Nice tip, Katie.

Nice Ride

I guess Jl19986 answered it best, it was not meant as any slight in any way. When ever I work with Suction Pumps, the skinny tube will always want to curl a bit. It was more of my opinion on it based on that the tube will not stay straight and go directly to the bottom of the pan. If it did, without a slight notch in the end of the hose, it would stop sucking well due to the tube possibly being flat on the bottom of the pan. ( all theories on my end ) if what Jl99.. said, it could be possible that suction from the fill tube would be best. The only way to confirm is to do the drain from the dip tube, then open the plug, unless someone on the forum can chime in that has possibly done this. I know for most people reading this, it does not matter. I like you enjoy working on cars with the simple stuff. The ramps are just something I've been doing for the past few years. I usually change the oil ( Extremely inexpensive at Walmart and free shipping ) after 6K or at least once a year no matter what the millage. I enjoy doing it. I hope when I'm your age, I can still tinker.... I maintain 3 Cars and 2 Vans, Lots of Oil.... When I use the ramps, it easily allows be to do a Brake Flush ( Every 2 to 3 years ) without removing the wheels.

Jud Chapin

No slight taken. I remember now why I jacked the Vette up slightly after draining the oil. It was because I was tilting the engine toward the drain plug allowing additional oil to be removed. As we know, the drain plugs are always off to the side of the pan to prevent it being ripped out if the car were to bottom out. Without this concern, the ideal drain plug placement IMHO would be in the middle of the bottom of the pan which would be slightly convex in shape. All I know is that these new cars are a pita because they are so low and must be raised if one is to drain oil from underneath. My '11 Lexus LS460 has the filter underneath meaning suction makes no sense as the car must be raised to get to the filter. Again, just my 2 cents.

chassis

Folks, oil, oil changing and tools to change oil are smoke and mirrors for consumers. It's a chance to sell someone something they don't need.

Mityvac (no offense to them) sells a marginally effective consumer gadget that is akin to a kitchen spatula. It's not professional equipment. Otherwise you would see professionals (dealers) using it. Skinny curly tubes, broken reservoirs and uncertain extraction experiences are a waste of time, effort and money.

The suction method is not faster, or you would see dealers using this method.

Synthetic oil is smoke and mirrors. https://en.wikipedia.org/wiki/Synthetic_oil. So-called "dino oil" is found as a base oil in most (all?) oils marketed as synthetic. Consider that changing the oil with frequency (5k miles is far too frequent, it's a waste of time, money and effort) is the most important aspect. Using store-brand so-called "dino oil" with the appropriate viscosity is adequate. Full disclosure: I use lubricants and change intervals specified by manufacturers. In the case of Mercedes, I used the Bevo site.

Katie gave excellent comments on the reason to drain oil at the MB specified temperature, that is so thermostats and control valves are open, and so that oil is at its lowest viscosity. This means oil is drained fully and quickly.

Fast and effective oil removal means gravity drain at high temperature. For consumers this can be a challenge. I get it. I have changed my share of oil on the garage floor in Michigan in February, multiple times. I have changed oil a couple of times in the driveway, in Michigan, in February. I have earned my stripes on this.

mahmoudim

I believe your motor oil might’ve been a bit cold. Run the car for a couple of minutes and bring the temp up. It will flow much easier.