Which is recommended/effective - draining or vacuuming out the oil?

Planning to do an engine flush and get out the nasty Magnatec and pour in some pure synthetic. What's the best way to make sure all the engine flush and magnatec is out?

Vac suction OR drip drain?

All theories welcome

[alfamoment]

vacuum??? seriously oil and en electric motor??
you never heard of sparks causing fires then?? flush and be patient the only way!

Originally Posted by alfamoment

vacuum??? seriously oil and en electric motor??
you never heard of sparks causing fires then?? flush and be patient the only way!

Are you suggesting the car will catch fire if the oil is removed by vacuum suction?

[Moonlightblue]

Have a look at the advantages and disadvantages of flushing. Personally (read: my opinion) sides with the school of thinking that flushing is not a great idea. The pressure of flushing systems (if it is indeed a pressure method you are using) is not good for the seals in the engine.
In the past, I have just drained out the old oil, replaced the filter, run the car for about 500km's and then done the process again. One might argue that this is a waste of a filter and oil, but then when put against the cost of a potentially detrimental flush, and that argument is done.
There is NO danger with draining normal oil, and switching to sysnthetic. Just make sure to change the filter.

Originally Posted by Moonlightblue

Have a look at the advantages and disadvantages of flushing. Personally (read: my opinion) sides with the school of thinking that flushing is not a great idea. The pressure of flushing systems (if it is indeed a pressure method you are using) is not good for the seals in the engine.
In the past, I have just drained out the old oil, replaced the filter, run the car for about 500km's and then done the process again. One might argue that this is a waste of a filter and oil, but then when put against the cost of a potentially detrimental flush, and that argument is done.
There is NO danger with draining normal oil, and switching to sysnthetic. Just make sure to change the filter.

It's more like a DIY flush I was planning to do at the lube station. By pouring in some STP Engine Flush in with the old oil, revving @ 2k rpm for 10mins, then draining every drop of the Magnacrap out of the car.

I've read some claiming it did wonders and few saying they began hearing strange knocks and it messed the seals etc. up. Not sure how a tiny can of engine flush could do such damage though.

[Moonlightblue]

Engine flush has chemicals and detergents in that are designed to strip (ok,maybe a harsh word) the old gunk away, and in doing so, can dislodge aformentioned gunk, only to have it clog up some other toleranced oil channel. It is probably not to kind on the seals either.
Completely draining the old oil away, and replacing it with synthetic is a common practice, and I am pretty sure the manufacturers (oil and vehicles) would put HUGE warnings on the bottles and engines saying not to do it if it was detrimental.
What is well known is that a lot of these 'additives' that people shove in their engines are marketing ploys, and there is no major support for the practice.

Get two filters, drain the oil and replace the filter, and then run it for a while (500 -1000km) and repeat. I reckon that would be the simplest, easiest and most practical.

[alfamoment]

Originally Posted by kia

Are you suggesting the car will catch fire if the oil is removed by vacuum suction?

no but the vacuum could unless you are using a special sealed type that prevents the oil fumes getting close to the electric motor and brushes inside (sparks ) .

unless you are using a hand vacuum pump in which case it is ok.