I presume this old question has raised it's head before but I couldn't find anything after a quick search, I did the oil yesterday, warmed it up first as usual and then removed the drain plug, left it drain away for a good while, I then got my vacuum kit and was amazed that I got another got 30cc's or so with this. also got a small amount out of cam cover. I'm so sorry I didn't video it as the purists seem to think you will never achieve anything like this. That proves it for me. Any thought folks?
General Using suction for oil change
- Thread starter digger58
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General Using suction for oil change
when I change engine oil either sucking it out via dipstick tube or draining it out I always start the engine and run it 5-10 seconds or so when it's all drained. This empties the crankshaft oilways and other pipework without damaging anything if it's kept short. You get a bit extra out that way.
Hi Digger. Is it really that important to get the last drop of oil out of the car?
Personally I dislike starting the the engine for the first time following an oil change, because of the slightly extended time without oil pressure while the pressure side of oil system fills.
Maximum wear occurs before oil pressure light goes out.
Maximum wear occurs before oil pressure light goes out.
This is totally wrong. Not only are you causing damage running the engine without oil it will also take much longer to "prime" the system when you start up with fresh oil. Thhis causes more damage.
you may not have symptoms, but you will cause damage.
DON'T DO THIS
If you really want a clean chaange, use a flush, either normal oil (cheap brand) or flushing oil.
Robert G8RPI.
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Couldn't agree more, exactly what I was attempting to say but more directly.
In the past I left a vehicle draining over night. The following day, after new oil and filter , nearly had a fit waiting for oil pressure light to go out. It took so much longer because pump and oilways had drained.
Ended up disabling ignition , removing spark plugs and cranking on starter for periods until oil light went out.
I thought it never would.
Pulling spark plugs , made it easier on starter but more importantly reduced load on big end bearings.
In the past I left a vehicle draining over night. The following day, after new oil and filter , nearly had a fit waiting for oil pressure light to go out. It took so much longer because pump and oilways had drained.
Ended up disabling ignition , removing spark plugs and cranking on starter for periods until oil light went out.
I thought it never would.
Pulling spark plugs , made it easier on starter but more importantly reduced load on big end bearings.
On some engines e.g. Rover V8, the oil pump won't prime if fully drained. After an engine rebuild on the V8 you have to pack the oil pump with petroleum jelly (vaseline, don't use grease) so it will prime.
Robert G8RPI.
Robert G8RPI.
If you can get near oil filter spin on threaded spigot pumping oil into centre usually goes straight to pump to.
I built up a 200tdi land rover block and wish I had packed pump as suggested , its been waiting rest of build for some time.
I built up a 200tdi land rover block and wish I had packed pump as suggested , its been waiting rest of build for some time.
Hi all.In the mid 60's, I recall there was a report that the cylinder bores of cars that were deprived of oil took 5-8 secs to become completely dry(dependent upon the speed of the car).I know oils are very different nowadays but would imagine the results would be similar.
I agree withg8rpi on this one.
digressing,Rover v8's 3500 what a car for it's time, brings back memories of Red Robbo. Cheers for that memory g8rpi. LOL
I agree withg8rpi on this one.
digressing,Rover v8's 3500 what a car for it's time, brings back memories of Red Robbo. Cheers for that memory g8rpi. LOL
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I would never start a car without oil, Again sucking out the oil is just getting out that bit extra, you will never get a full change unless the engine is stripped each time. When I do start it, I just let it idle till light goes out. Spent too many years on heavy plant to rev a cold engine or indeed to shut down a hot engine quickly.
This is totally wrong. Not only are you causing damage running the engine without oil it will also take much longer to "prime" the system when you start up with fresh oil. Thhis causes more damage.
you may not have symptoms, but you will cause damage.
DON'T DO THIS
If you really want a clean chaange, use a flush, either normal oil (cheap brand) or flushing oil.
Robert G8RPI.
Where the hell do some get their ideas! Don't be starting an oil less engine
I'm not going into the oil change as it causes umbrage to some..
Every cold start is with totally dry cylinders and oilways drained off, most oil pumps also empty themselves overnight which is why they are located as near the oil level as possible. Rebuilt engines start up dry apart from what you squirt on during the build, which has gone by the time you get the unit back in place. But with my method the engine is still warm because I never change oil cold, I suck it out in 5 minutes so everything is still oily. Anyway, I never ever get engine trouble down to lubrication issues and I've done it on 50 cars over 55 years, I'm not going to stop now because somebody differs over it. It's far less harmful than a cold start in either winter or summer I'm quite sure. And don't think the rubber flap in a spin-on filter will stop it from emptying, because it won't. As for engine flush systems, they certainly seem to work, perhaps too well if you look at what they bring out of some old engines. But I don't feel sure about putting that stuff in, maybe it softens oil seals, or perhaps hardens them?
I don't share your opinion that all the oil drains down to the sump overnight.
The evidence is the very same car that I drained over night which then took ages for oil light to extinguish. The same car left over night in normal use , the oil light would go out immediately on cranking. Therefore clear oil ways and pump had not drained fully to sump over night.
I have also found the anti drain valves in some oil filters to be effective, try blowing through a new one with your breath.
I am not going to address correct procedures for starting a fresh engine its outside this thread.
You are not going to change your method this is just a different view with the reasoning behind it.
The evidence is the very same car that I drained over night which then took ages for oil light to extinguish. The same car left over night in normal use , the oil light would go out immediately on cranking. Therefore clear oil ways and pump had not drained fully to sump over night.
I have also found the anti drain valves in some oil filters to be effective, try blowing through a new one with your breath.
I am not going to address correct procedures for starting a fresh engine its outside this thread.
You are not going to change your method this is just a different view with the reasoning behind it.
Quote "It's far less harmful than a cold start in either winter or summer I'm quite sure."
just an opinion but think far more harmful because on a cold start oil flow starts immediately the engine turns , evidence the oil light goes out within a fraction of a second.
You are running the engine for 10 to 15 seconds with zero oil flow and zero oil pressure.
think of the running loads on the very soft white metal bearings, big end and mains, white metal bearings can be damaged by a finger nail.
these bearings must have a constant supply of clean oil.
Have you used your technique on diesel engines?
just an opinion but think far more harmful because on a cold start oil flow starts immediately the engine turns , evidence the oil light goes out within a fraction of a second.
You are running the engine for 10 to 15 seconds with zero oil flow and zero oil pressure.
think of the running loads on the very soft white metal bearings, big end and mains, white metal bearings can be damaged by a finger nail.
these bearings must have a constant supply of clean oil.
Have you used your technique on diesel engines?
yeah i wouldnt start with it drained ever, i don't personally think getting every drop out is even remotely necessary. Well if you do regular changes then its not something i think is worth worrying about.. Every few oil changes I will drain and then put some clean in and run it for few mins and then drop that stuff out and then change the filter and fill up with the stuff I am gonna leave in there. I wouldn't even bother with engine flush unless i was deal with a car i knew had not had a oil change in a very long time and has some sludge in there a normal change wouldn't clear.
On most cars I fill the new filter up with oil before I put it on but not really doable on the fire engines with the filter sitting at a sideways angle, my suzuki for example the oil filter points straight down so you really can fill it right up and then screw it on and not spill a drop.
But you know 99% of the time i just drop the oil, change the filter and then fill up with new oil. My oil stays looking brand new and nice and golden for quite a long time after so there is not much oil residue left in the engine really, not enough to worry about thats for sure. Can't say I have ever really noticed it taking longer to build pressure after a change compared to just a normal start but you can just disconnect the crank sensor on these and you get no spark and fuel and just turn it over until there is pressure. But I suspect that just starting it will build pressure faster as the engine will spin the oil pump much quicker than the starter but as said above, from just a change everything is gonna still be coated in oil when you first start it, its not like starting a dry engine thats not been used for months or years.
On most cars I fill the new filter up with oil before I put it on but not really doable on the fire engines with the filter sitting at a sideways angle, my suzuki for example the oil filter points straight down so you really can fill it right up and then screw it on and not spill a drop.
But you know 99% of the time i just drop the oil, change the filter and then fill up with new oil. My oil stays looking brand new and nice and golden for quite a long time after so there is not much oil residue left in the engine really, not enough to worry about thats for sure. Can't say I have ever really noticed it taking longer to build pressure after a change compared to just a normal start but you can just disconnect the crank sensor on these and you get no spark and fuel and just turn it over until there is pressure. But I suspect that just starting it will build pressure faster as the engine will spin the oil pump much quicker than the starter but as said above, from just a change everything is gonna still be coated in oil when you first start it, its not like starting a dry engine thats not been used for months or years.
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People get obsessed with these things.
Drain the oil off, take the filter off, new filter on, put the drain plug back and top up with new oil.
That is as complicated as an oil change needs to be, if you want to go through the unnecessary processes of literally flushing your money through the engine and in to a bin with flushing fluids or cheap oils feel free but it's not really going to do anything for a well maintained regularly serviced engine.
If you want to run your engine for 10 seconds with no oil in to get a few measly drops of extra oil out feel free. Just consider that with no oil pumping there is nothing to push the oil out, so the only extra oil you get out is pushed out by friction between components and potentially putting little fragments of metal in your nice clean oil to spend the next 12 months traveling the internals of the engine. Tolerances in oil pumps are very small and that's where you'll do the most damage. So the more you run your car without oil the less effective the oil pump will become, even if everything all appears well.
I'd be interested in auction devices for oil changes if it lets you get a few extra ml of oil out (not just a few drops), which I believe they do. Far more effective than any other method.
Drain the oil off, take the filter off, new filter on, put the drain plug back and top up with new oil.
That is as complicated as an oil change needs to be, if you want to go through the unnecessary processes of literally flushing your money through the engine and in to a bin with flushing fluids or cheap oils feel free but it's not really going to do anything for a well maintained regularly serviced engine.
If you want to run your engine for 10 seconds with no oil in to get a few measly drops of extra oil out feel free. Just consider that with no oil pumping there is nothing to push the oil out, so the only extra oil you get out is pushed out by friction between components and potentially putting little fragments of metal in your nice clean oil to spend the next 12 months traveling the internals of the engine. Tolerances in oil pumps are very small and that's where you'll do the most damage. So the more you run your car without oil the less effective the oil pump will become, even if everything all appears well.
I'd be interested in auction devices for oil changes if it lets you get a few extra ml of oil out (not just a few drops), which I believe they do. Far more effective than any other method.
If you read about performance engine building the experts all seem to agree that the component most at risk from an oilless startup is in fact the camshaft lobes and lifters. Modern OHC cars solve this by little reservoirs that can't drain, for the lobes to dip in so protecting the cam. Crankshaft bearings will always be oily after a 5-minute drainoff, and in any case none are white metal these days, that metal went out of use in engines at least 70 years ago. They are either aluminium-bronze or copper-lead on a steel back and are very hard wearing. One of those fake oil additive makers ran a car for 150 miles without oil, after having run it for a while using their product, they claimed no wear took place. I don't believe it and neither will you, but engines can be quite robustly made these days.
