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Read the WELCOME ALL BMWFANATICS post.
Engine oil flush during an oil change.........
- Thread starter Roundal
- Start date
D
Dippies
Guest
+1
Z3Zack said:Roundal said:
My opinion would be that if you service regularly and you use proper oil, a flush isn't really necessary. When I was still running my Mazda I used to drain the oil, put in new oil, go for a short drive, drain and top up again. That's my perspective on a good flush.
wait....you drain oil. fill up with new oil. drive, short distance, then drain again? Everything? Reason I ask is becuase the second oil addition you say "top up". How much do you drain the 2nd time?
Zack
///Member
ambroseg1 said:Z3Zack said:Roundal said:
My opinion would be that if you service regularly and you use proper oil, a flush isn't really necessary. When I was still running my Mazda I used to drain the oil, put in new oil, go for a short drive, drain and top up again. That's my perspective on a good flush.
wait....you drain oil. fill up with new oil. drive, short distance, then drain again? Everything? Reason I ask is becuase the second oil addition you say "top up". How much do you drain the 2nd time?
I completely drain it again. Should have said fill up instead of top up
When I can afford it I buy 10 liters (2X 5L containers) of whatever I will be putting in + a 500ml bottle or two.
I then drain and top up to the lower mark on the dipstick (around 4 Liters) and go for a nice long drive, drain again, replace filter and fill with the remaining oil.
Thinking about this technically it's probably a complete and utter waste of time and money, but it makes me feel better so I do it anyway.
(When I recently tried to get water contaminated oil out of an engine I realised even three full changes still leaves a lot of the old stuff in)
I then drain and top up to the lower mark on the dipstick (around 4 Liters) and go for a nice long drive, drain again, replace filter and fill with the remaining oil.
Thinking about this technically it's probably a complete and utter waste of time and money, but it makes me feel better so I do it anyway.
(When I recently tried to get water contaminated oil out of an engine I realised even three full changes still leaves a lot of the old stuff in)
Nic_s
///Member
If you just bought a car and don't know what oil is in it, then I can understand doing a "flush" where you drain the old oil, top up with new oil, drive, drain again, and then replace filters and fill with new oil. Not sure it's really needed with every service you do after, but it couldn't hurt.
For me, when it comes to things like oil, keeping it simple is usually best.
For me, when it comes to things like oil, keeping it simple is usually best.
M
Mike1
Guest
There are specific scenario's where a flush is absolutely essential.
1. Changing Oil Bases. Most cars have either a mineral, hydrocracked or Semi-Synthetic Oil in them. They offer superb lubrication with minimal expense. This is the oil the dealers use and usually have all the approvals required for your car.
These oils all derive from a Mineral Base, with additives added to give them their unique properties. However with a Fully Synthetic the base is usually made specifically for the oil and is a Synthetic Base.
I am not going to go into too much detail about Base Groups etc here okay.
You cannot mix bases. This means that if you have a Hydrocracked Oil like Castrol SLX in the motor and you want to put in a Fully Synthetic you have to flush it. If not the remaining Hydrocracked Oil coating all 350 odd moving parts in the engine will contaminate the new oil and of course we dont want this.
A flush wont be necessary when replacing oil with a similar base. So for example you can drain Castrol SLX and replace it with Liqui Moly Longtime High Tech without a problem. They are both mineral base and are compatible, whatever "mixing" that does occur will make little difference to the new oil.
So if changing from a Mineral Base to a Synthetic Base or vice versa you must Flush!
2. Sludge.
With a motor which has either not been serviced on time, or had the incorrect oil in you must flush. Sludged motors will have considerably higher traces of engine wear in them and it is advised that this be flushed out before replacing with new oil.
However in some cases an engine flush is not advised at ALL!
For example we were recommended not to use flushes in cars with more than 150 000km because of the larger engine tolerances, we were also advised never to drive the car with a flush in and never to use a flush for more than 10 minutes at a time.
I sold a huge amount of Liqui Moly Engine Flush and used it quite often myself... With just 10 minutes idling the oil would come out the motor like water and this was on a Hyundai Accent that hadnt been serviced for over 40 000km. :yuck:
Mike
1. Changing Oil Bases. Most cars have either a mineral, hydrocracked or Semi-Synthetic Oil in them. They offer superb lubrication with minimal expense. This is the oil the dealers use and usually have all the approvals required for your car.
These oils all derive from a Mineral Base, with additives added to give them their unique properties. However with a Fully Synthetic the base is usually made specifically for the oil and is a Synthetic Base.
I am not going to go into too much detail about Base Groups etc here okay.
You cannot mix bases. This means that if you have a Hydrocracked Oil like Castrol SLX in the motor and you want to put in a Fully Synthetic you have to flush it. If not the remaining Hydrocracked Oil coating all 350 odd moving parts in the engine will contaminate the new oil and of course we dont want this.
A flush wont be necessary when replacing oil with a similar base. So for example you can drain Castrol SLX and replace it with Liqui Moly Longtime High Tech without a problem. They are both mineral base and are compatible, whatever "mixing" that does occur will make little difference to the new oil.
So if changing from a Mineral Base to a Synthetic Base or vice versa you must Flush!
2. Sludge.
With a motor which has either not been serviced on time, or had the incorrect oil in you must flush. Sludged motors will have considerably higher traces of engine wear in them and it is advised that this be flushed out before replacing with new oil.
However in some cases an engine flush is not advised at ALL!
For example we were recommended not to use flushes in cars with more than 150 000km because of the larger engine tolerances, we were also advised never to drive the car with a flush in and never to use a flush for more than 10 minutes at a time.
I sold a huge amount of Liqui Moly Engine Flush and used it quite often myself... With just 10 minutes idling the oil would come out the motor like water and this was on a Hyundai Accent that hadnt been serviced for over 40 000km. :yuck:
Mike
M
Mike1
Guest
Assuming you are not mixing bases then Budleigh is 100% correct. :thumbs:
while we on the subject...
changing over to mobil 1 from hydrocrap? good idea or bad idea at 180 000 km... i beat my car every day and i think it needs better oil...
obviously i would have to flush to change over... but will the engine not like the change?
changing over to mobil 1 from hydrocrap? good idea or bad idea at 180 000 km... i beat my car every day and i think it needs better oil...
obviously i would have to flush to change over... but will the engine not like the change?
So when will my toyotas engine seize or be damaged because I have changed from non-synthetic to synthetic without flushing and the motor has over 400 000km on? Has done 5000 km thus far after the oil change and it seems in the best nick ever. Is it going to surprise me when blows it up, or when can I expect disaster? :blab:
M
Mike1
Guest
Guys it doesnt mean it will explode straight away! :rollsmile:
Its just not recommended.
Moranor, stick with your Hydrocracked oil, your motor does not require a massive spec oil and Mobil 1 will just be wasted.
ambroseg1 -
Actually no. Tell me in the other thread exactly the Royal Purple Oil you used before I recommend anything.
Its just not recommended.
Moranor, stick with your Hydrocracked oil, your motor does not require a massive spec oil and Mobil 1 will just be wasted.
ambroseg1 -
Actually no. Tell me in the other thread exactly the Royal Purple Oil you used before I recommend anything.
answered in the other thread. Royal Purple HPS 10w40 oil. Added the link but here it is also... http://royalpurpleconsumer.com/product-categories/automotive/#!hps-motor-oilMiniMike19@DefinitiveAuto said:
Philip Foglar
///Member
Personally I am bit terrified of using an engine flush or other additives for that matter. My idea is to also stick to the recommended oil and just change the oil at least once a year since I don't do very high mileage. Well, I am hoping that this will do the trick!
Raybimmer
New member
Mike , needless to say you obviously know the old wives tales and " it was ok for grandad , its ok for me " mentalities .Why do containers of oil not indicate V.I . , I regard it as important ?
My belief , a correctly lubricated ( grade of oil and drain intervals ) machine will not need a flush . If the vehicle has stood for long times or only done short trips it may have sludge buildup , then flush it .
If everyone accepts that two machined surfaces rubbing against each other can be seen as a sawtooth pattern under a microscope . The peaks will break off in the running in period , and they do not fall over and fill the valleys to create a smoother surface . If this keeps on happening your engine wears out as the working clearances increase . ( Now put your super thin oil in these large clearances , ever had sex with a virgin and a mother of six ?? - same thing !! )
A good quality oil will disperse these metal particles to the oil filter , you see the oil gets dirty , it is carrying particles in suspension away from working surfaces , which is a good thing as they are cleaned . Then a flushing agent ( sorry liquid !! ) will not be required .
My belief , a correctly lubricated ( grade of oil and drain intervals ) machine will not need a flush . If the vehicle has stood for long times or only done short trips it may have sludge buildup , then flush it .
If everyone accepts that two machined surfaces rubbing against each other can be seen as a sawtooth pattern under a microscope . The peaks will break off in the running in period , and they do not fall over and fill the valleys to create a smoother surface . If this keeps on happening your engine wears out as the working clearances increase . ( Now put your super thin oil in these large clearances , ever had sex with a virgin and a mother of six ?? - same thing !! )
A good quality oil will disperse these metal particles to the oil filter , you see the oil gets dirty , it is carrying particles in suspension away from working surfaces , which is a good thing as they are cleaned . Then a flushing agent ( sorry liquid !! ) will not be required .
I am not fond of these flushes as I have once wrecked a very old engine by flushing it as the carbon and dirt was holding it together lol. it smoked like crazy once it was "cleaned"
An engineer friend and I were discussing the use of engine flushes the other day. he explained he only uses it after measuring the amount of oil that he drains. For example if your engine takes 5.5 liters and you are on the top dipstick mark and drain out only 4.5 liters then you have 1 liter of sludge inside!
If the correct quantity drains out you do not need to flush as there is no sludge problem. If not there is some "jelly" in your sump that needs to be disolved by flushing.
An engineer friend and I were discussing the use of engine flushes the other day. he explained he only uses it after measuring the amount of oil that he drains. For example if your engine takes 5.5 liters and you are on the top dipstick mark and drain out only 4.5 liters then you have 1 liter of sludge inside!
If the correct quantity drains out you do not need to flush as there is no sludge problem. If not there is some "jelly" in your sump that needs to be disolved by flushing.
rick540 said:
+1
Don't look for issues where there are none.
Best thing is to monitor the oil colour, if it gets dirty, do an oil and filter change. The more regular the better. Oil is the life blood of an engine after all.
If you are unsure about a used vehicles history with oil services and sludge build up rather get the sump pulled and cleaned. Ensures you starting with a clean slate. :thumbs:
