oil extractor
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Caporegime
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You must change the oil once every 10 - 12k, which at a guess is around once every 10 months, it takes about 5 mins to jack up one side of the car and put it on axle stands, it's not worth taking all the negatives about using an oil extractor for something you do so infrequently imho.
Some particles will be too heavy to be sucked up the pickup, and under certain circumstances oil doesnt get filtered, and just goes straight through the filter bypass valve
after what ive seen in sumps, i wouldnt want to use a pump, thats a shortcut for lazy garages.
sumps collect things like burnt/caked on oil that drops into the sump. that normally gets washed out when you dump the oil, failing that it gets stopped by the screen for the oil pump, which lowers oil pressure.
only thing to gain from a pump is quicker oil changes, but at teh cost of doing it properly
sumps collect things like burnt/caked on oil that drops into the sump. that normally gets washed out when you dump the oil, failing that it gets stopped by the screen for the oil pump, which lowers oil pressure.
only thing to gain from a pump is quicker oil changes, but at teh cost of doing it properly
Its not at all a shortcut for lazy garages, some cars dont have a sump plug any more, pretty sure the smart car needs to be extracted from the top. Boats have been using them for years as well, if your getting loads of swarf something is very wrong with your engine.
Caporegime
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Engines wear as they age, it would be impossible for them not to, the 'wear' has to go someplace so it ends up in your sump.
Simple fact is you can't remove as much oil with an extractor as you can by taking it out the bottom of the sump, for the sake of an extra 5 mins work i'd rather remove as much old contaminated oil as possible and replace with new.
If the oil has been changed at appropriate intervals then there won't be any sludge or swarf built up in the sump. IME the vacuum pumps get as much or more oil out of the sump than the sump plug does.
Which will then get picked up and caught in the filter. "Wear" does not cause huge chunks of metal that can't get past the pickup screen.
A simple fact that is also incorrect.
Caporegime
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Not always, it depends if you've got a magnetic drain plug or not, buildup of swarf on the drainplug over time can cause lumps to finally drop off which in turn get sucked up by the oil pump, a large amount of which at a single time can cause issues, the screen pickup on the oil pump simply isn't fine enough for this purpose.
So you could be left with the situation of never checking the drain plug for buildup cause you've never removed it.
An oil extractor is a simple suction pump is it not, create a vacum in the bottle which sucks up oil through a tube, unless you poke the tube into ever corner of the oil pan how can it get everything out?
So how do those cars with drain plug cope?
A sump plug is located only in one corner or one edge of the sump is it not? Unless there is a plug located on every edge, how can it get everything out?
I've used a vacuum pump to drain oil from my Fiat Coupe, my ZS180 and my wifes Hyundai Coupe. In all cases undoing the sump plug afterwards releases no more than a few drips of oil.
Caporegime
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You jack up the opposing front corner, for instance my drain plug is located rear driver side of the sump, i jack up the front passenger’s side, hey presto all the oil flows downhill.
Since an oil suction pump can't create a vacuum in the oil system it simply can't get all the oil out, this is further compounded if you've got a baffled sump since it becomes impossible to get into all areas with the suction tube.
I've used one before it got most of the oil out but not everything, doing it the 'old way' takes an extra 5 mins and saves me £30 on a suction pump, coupled with the fact that some cars such as mine need to be jacked to get the oil filter out taking the sump plug out becomes a no brainer.
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No it isn't
Not all cars even drain all the oil out, so what about them, when i do an oil change you only change about 4.5 litres but it holds 8+litres? So why is it crucial as you keep suggesting to drain 100% out? The extractors are fine, you can even drain the oil while its extremely hot as you dont need to come in contact with it.
Associate
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neither does mavity
Okay even if it had a baffle in the normal sense it would hold oil as well for a mavity drain. for the record baffles in oil (and petrol tanks) have holes to allow the (slowed)movement of fluid.
IF you could get the suction nozzle in the same place as the sump plug they would remove the same amount of oil, the advantage to the plug removal would be to inspect the magnetic plug for metal debrise.
Bullit
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And that's a massive IF, some dipstick tubes won't even allow you to stick the oil extractor all the way down meaning you only get the top 1ltr out of the sump.
Correct however in a mavity driven situation the oil has to flow to the low point, given the above point a suction based system may not have access to the low point in the sump, be this due to sump design / dipstick tube design or baffles in the way.
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Associate
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smart cars don't have a sump plug so you would need a pump/extractor to get all the oil out - there might be other cases for using them too, it's not all about laziness or being able to jack your car up correctly.
Caporegime
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I can only conclude this idea was also dreamt up by the same guy that removed the dipstick and told everyone to rely on the electronic oil level gauge in the sump, I gave him a 10/10 for that idea too.