oil change, suction or drop it

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I would always drop the oil out, I just think its better letting all the stuff on the bottom drain out for ten minutes. Sucking out would be easier though and probably less messy and so better health and safety wise.


The suction method drains the oil from the bottom of the sump..
You push the tube all the way down the dipstick tube until it hits the sump floor...

My C270CDi holds 6.5 litres of oil.. When I use the Pela oil extractor I remove 6.5 litres of oil.
Some time ago I put a post up on here saying that if I could be bothered i would arrange to have the use of a 4 wheel lift..Then I would use the Pela oil extractor and then remove the sump plu to see what came out (if anything)..
I got a reply post from a forum member who had done just what I had contemplared..
He said NOTHING CAME OUT when he removed the sump plug !!

Also please keep in mind that if you put your car on ramps then your enginge is tilted backwards..Fine if you happen to have a sump drain plug on the rear of the sump... BUT many cars have the drain plug either on the front or half way along. In this case you would NOT be draining all the engine oil !

I should have been a salesman for Pela because everyone that I have demonstrated the pump to has gone out and bought one.

I will NEVER, EVER grovel beneath a car again as long as I live..
 
USED THE SUCTION METHOD FOR YEARS WITHOUT A PROBLEM. The only exception might be if you bought a car which had not had the oil drained properly for years. Then it might be worth gravity draining from the sump while hot and then using a flushing oil to repeat the process. This would be followed by a normal oil and filter change and vacuum removal used thereafter. As usual with these arguments quite often the "human element" needs to be taken into account. The hidden advantage of Vacuum aspiration is that its so easy and clean that any DIY owner is likely increase the frequency of oil/filter changes rather than put it off to the last minute. Once you have sucked rather than drained you won't look back.
 
"Also please keep in mind that if you put your car on ramps then your enginge is tilted backwards..Fine if you happen to have a sump drain plug on the rear of the sump... BUT many cars have the drain plug either on the front or half way along. In this case you would NOT be draining all the engine oil !"

On my car if I reverse up the drive and check the oil (car sloping forwards) I get a lessler reading on my dipstick.
If I drive up and park (car sloping backwards) I get more reading on my dipstick even when compared to parking the car flat.
I thus concluded that both the 210 and 211 must have the dipstick nearer the rear...
Although if the sump is designed for vacuum extraction I'm guessing the sump slopes in to the dipstick, to ensure everything gets removed.
 
What must be remembered is that, regardless of suck or drop, merc and most manufacturers recommend using a flushing oil to get rid of the gunk.

Recommended best practice is remove oil from warm engine (sounds stoopid but make sure its turned OFF before draining), refill with flushing oil, run for the recommended length of time (on flushing oil label) and remove as before, then top up with fresh oil.

If a gallon or more flushing oil is too expensive, or time is a problem, use a flushing additive to your existing oil.

With suction extraction, flushing is arguably much more important (sorry for the grammer)
 
ok. maybe being stupid here. i have a w203 cdi, no dip stick, how do i suck it out?
thanks
 
You have no dipstick but you will have a dipstick tube with a cap on it -possible red or black. It may have a tamper proof seal on it which you will have to break and possbily replace-you may be able to use the old one again tho. You can buy cheap dipstick tools on E bay to measure the oil level when you renew the oil - which I would recommend - if not - if you are happy that the existing pre-drain oil level was correct then catch and measure the volume of old oil you drain out and replace it with the same volume of new--- there is always some left in the engine and if you use the standard fill volume as per manufacturer spec you run the danger of overfilling.
 
Modern cars its ok to suck it out, with older cars that may have a build up of sludge, its not ok... period, there is simply no argument!

However here at work we always drain through the sump plug... just to be sure.
 
suck is the easiest way. However you will always get more out and more gunk if you drain it. Drain bung is always at lowest part of sump. Putting a pipe into dipstick can never ensure you are at the lowest point of the sump.

Also the pump tube is narrower diameter than a bung. Therefore oil will empty more slowly allowing the debris (if any) time to settle out before being sucked. Opening a bung you get a cascade of oil dragging anything with it
 
You have no dipstick but you will have a dipstick tube with a cap on it -possible red or black. It may have a tamper proof seal on it which you will have to break and possbily replace-you may be able to use the old one again tho. You can buy cheap dipstick tools on E bay to measure the oil level when you renew the oil - which I would recommend - if not - if you are happy that the existing pre-drain oil level was correct then catch and measure the volume of old oil you drain out and replace it with the same volume of new--- there is always some left in the engine and if you use the standard fill volume as per manufacturer spec you run the danger of overfilling.

There is NONE left in the 270 CDi engine..
Obviously the design of engines varies and so yes you maybe will miss a cupful.
But in 5 - 6.5 litres so what !!
 
You have no dipstick but you will have a dipstick tube with a cap on it -possible red or black. It may have a tamper proof seal on it which you will have to break and possbily replace-you may be able to use the old one again tho. You can buy cheap dipstick tools on E bay to measure the oil level when you renew the oil - which I would recommend - if not - if you are happy that the existing pre-drain oil level was correct then catch and measure the volume of old oil you drain out and replace it with the same volume of new--- there is always some left in the engine and if you use the standard fill volume as per manufacturer spec you run the danger of overfilling.

..and don't confuse the oil filler tube with the ATF tube (if you have an auto gearbox), as happened to another forum member here... sucking out ATF is not good for your car.:doh:
 

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