Pump oil out v sump plug oil change?

[anonymous-user]

[redacted]

[Hereward]

I use a manual vacuum extractor via the dipstick. Makes life very simple.

Only downside I can think of is that you may not be able to extract quite as much compared to a sump plug gravity drain.

[anonymous-user]

A lot of garages do it that way now. Personally I find it much easier than messing around under the car, especially if the oil filter is also located somewhere accessible without having to get under the engine. I spend a bit of time jiggling the pickup hose around to get as much as possible out, but TBH there is always some old oil left in the engine whatever you do.

[bungz]

Depends where the oil filter is to whether it makes any sense.

On mine sadly at back of block from under car so no easy changes for me.

[W00DY]

You can also pump the old easily and tidily into a container ready for taking to the tip. Plus no chance of having a leaking sump plug (if you don't have one already that is)


If your battery is at the other end of the car to your engine, then you'll need another power source or to remove it.

[Hereward]

anonymous said:

[redacted]

I have one of these, bought it online. Plunge the, er, plunger a few times to create a vacuum then stand back and admire...

http://www.pelapumps.co.uk/default.aspx?A10PAGE=PL...

[Krikkit]

I would always drop the sump plug out, being more confident that you've got as much oil (and the heavier sludge you sometimes get at the bottom of the sump) out.

And the filter for the canister types always makes a mess anyway... The paper filter types are usually OK mind.

[DaveCWK]

I remove the sump plug but on all the car's i've ever done it on you have to go underneath to remove the oil filter anyway.
Depending on any baffling there is in the oil pan, could sucking out via dipstick not actually leave quite a lot?

[B'stard Child]

Hereward said:

I use a manual vacuum extractor via the dipstick. Makes life very simple.

Only downside I can think of is that you may not be able to extract quite as much compared to a sump plug gravity drain.

I was hugely skeptical many years back - regarded them as a short cut to doing the job properly and they would never remove all the oil etc etc

Then I bought an SLK with a very heavy steel undertray (was an expensive option I believe) - it really took two people to get it bolted back on the car so after the first change I bought an extractor because it really wasn't a fun job.

A year into it's life I took the undertray off and got it blasted and coated and while it was off I did an oil & filter change with an vac extractor pump (via dipstick) As it was easy to drop the drain plug out with no undertray I then dropped the sump drain plug to see what it had missed - I was shocked!!!!

Not even half an egg cup of oil had remained in the sump - there was probably more oil than than in the head and oil galleries

I've since done the same test on other cars I own and in every case the quantity of oil left in the sump has negligible.

I'm a convert now but latest daily is fitted with an N52 engine and it doesn't have a dip stick

[B'stard Child]

Hereward said:

I have one of these, bought it online. Plunge the, er, plunger a few times to create a vacuum then stand back and admire...

http://www.pelapumps.co.uk/default.aspx?A10PAGE=PL...

I have same one - very good bit of kit unless your sump capacity is more than 6.5 Litres (then you have to do the extraction in two stages)

[Richard-390a0]

Depends on the vehicle. One of the AMG engines in the 211 E Class had a double sump so you had to drain it from the underside... not that most of the techs I worked with did...

[Hereward]

B'stard Child said:

Hereward said:

I have one of these, bought it online. Plunge the, er, plunger a few times to create a vacuum then stand back and admire...

http://www.pelapumps.co.uk/default.aspx?A10PAGE=PL...

I have same one - very good bit of kit unless your sump capacity is more than 6.5 Litres (then you have to do the extraction in two stages)

Exactly right. My V12 needs a two stage extraction so I can't wander off for a cup of tea.

I notice that Pela do a 14 litre reservoir...tempting.

[Boosted LS1]

The vacuaam kit is what we use on inboard marine engines where access to the lower part of the engine's impossible. It's slow but works very well.

[Hol]

I have always dropped the sump plug, but this has got me thinking.

Although, on a new to me car, where the last change and quality of oil is unknown. I will probably do the first one the old way, so I can drain the lot.

[mickyh7]

W00DY said:

You can also pump the old easily and tidily into a container ready for taking to the tip. Plus no chance of having a leaking sump plug (if you don't have one already that is)


If your battery is at the other end of the car to your engine, then you'll need another power source or to remove it.

My battery is in the back but there are 'Jumping' points under the bonnet to attach the Crocodiles!

[Captain Answer]

If the filter is down the bottom then I do both.... If the filter is up the top I will just use the pump

12v pump makes it a much less messy job, especially if I'm doing all 3+ family sheds in the one day

I have this one.. https://www.amazon.co.uk/gp/product/B004VEF1G4/ref...

I had a vaccum pump before but it never seemed to work right for me

[105.4]

Krikkit said:

I would always drop the sump plug out, being more confident that you've got as much oil (and the heavier sludge you sometimes get at the bottom of the sump) out.
.

This ^^^

I’d always favour dropping the oil, or to use another phrase, ‘doing the job properly’.

[Captain Answer]

105.4 said:

This ^^^

I’d always favour dropping the oil, or to use another phrase, ‘doing the job properly’.

Prob best not to look under a smart car then, they don't have a sump plug

[AllyBassman]

My car takes 8.5L of oil,

When I come to change it via the extraction pump I get near as makes no difference 8.5L out.

So yes, it is the job 'done properly' in my book. Difference is I don't need to get under the car at any point. Plus my oil filter lives at the top of the Engine bay so it's even easier!

To be fair I have read numerous times that the extraction pump is Mercedes chosen method for oil changes at the dealerships, I don't know how true this is.

If you use good quality oil and stick to your serivce shedule - I see no reason to worry about a tiny bit of oil left in the sump.

[105.4]

Captain Answer said:

Prob best not to look under a smart car then, they don't have a sump plug

I didn’t know that. Mind you, with Mercedes it wouldn’t surprise me. Anything to save £0.50 per car made.