Oil change with warm or cold oil?

[wolfehunter]

This car has been parked since November in a non-heated cement floor garage in central PA. My past practice has been to start the car and drive until up to temp and change the oil. Is that recommended? Or is it wiser to drain the cold oil out of the pan over the next few days and refill with fresh oil and a new filter?

Would the fresh oil run down over the internal parts and pre-lubricate them before initial start up?

Where does the moisture form in an engine that has been sitting? Laying on top of the oil in the pan or clinging to internal parts?

I am thinking it is probably better to fire it up with old oil in it and mix all the water and oil together and then drain it but was looking for thoughts.

 

[Nick1994]

I'd drain it cold, after you start it, oil will drip for a long time from the upper end, IMO you'd probably get more old oil out at cold.

 

[HemiHawk]

I would probably drain it cold, since all of the old oil is already sitting at the bottom. A warmish day or two may help it flow out.

After refilling (or if you decide to fire it up with the old), you may be able to crank the engine without starting to circulate some oil before starting since its been sitting for so long. depending on the year of this car, a "clear flood mode" may be available. I know for a manual car its just clutch down, gas pedal straight to the floor, then turn the key. the engine will turn at cranking speed, but not fire. Could reduce initial wear on an engine that hasn't run in so long, but maybe not necessary.

 

[aquariuscsm]

I actually prefer to change fluids with the car undriven/unstarted at least from overnight,but mine sits so low that it has to be started and driven up on ramps to get underneath it.

 

[Nick1994]

Originally Posted By: aquariuscsm
I actually prefer to change fluids with the car undriven/unstarted at least from overnight,but mine sits so low that it has to be started and driven up on ramps to get underneath it.
What if you park it on ramps overnight?

 

[tomcat27]

moisture is everywhere: in the oil, though mostly on the parts. I would warm up the oil - it will help remove all of the contaminents.

 

[demarpaint]

Originally Posted By: tomcat27
moisture is everywhere: in the oil, though mostly on the parts. I would warm up the oil - it will help remove all of the contaminents.


I agree. Depending on how the car is set up, I'd crank it so it doesn't start and let it turn over a bit. Then fire it up and take it for about a half hour ride and drain the oil.

 

[daman]

Don't start it, the oil has already drained off parts and down into the pan nicely. Being it's cold it will require longer time to drain, if the car isn't needed right away give it time and let it drain a day or two.

Any moisture will be burnt off with the first drive.

 

[Bgallagher]

Originally Posted By: daman
Don't start it, the oil has already drained off parts and down into the pan nicely. Being it's cold it will require longer time to drain, if the car isn't needed right away give it time and let it drain a day or two.

Any moisture will be burnt off with the first drive.


+1 Considering how long the vehicle has remained stationary most of the oil etc. will be in the pan

 

[53' Stude]

I like to go for a nice 30 minute drive to make sure the oils up to temp. That's just my thoughts

 

[TomYoung]

I am wondering why you feel the need to drain the oil. If the oil is old and needs draining, then warm the car up and drain it.

If the concern is that there is a lot of moisture in the engine, please know that oils can hold some water in emulsion without any ill-effects to the engine. Know also that moisture will evaporate off completely after an hour or two if the engine is running properly.

Lastly, you should also know, contrary to some of the earlier comments, that oil will find its way to the bottom of the sump and the oil will float above it. This is a slight problem, in that the water could flow through the engine first at startup when it is picked up by the oil pickup.

Your car parts are a heck of a lot more likely to have an oil coating than a water coating.

 

[6starprez]

Either or, it probably doesn't matter. How old was the oil in the crankcase prior to sitting up for 5 months?

 

[yvon_la]

Hot. Still have to let it sit. Not so it cool off but to get most of the oil in then. Bring it to temperature thrn plug it like in winter.

 

[PeterGreen]

so we have a perfect consensus.

 

[aquariuscsm]

Originally Posted By: Nick1994
Originally Posted By: aquariuscsm
I actually prefer to change fluids with the car undriven/unstarted at least from overnight,but mine sits so low that it has to be started and driven up on ramps to get underneath it.
What if you park it on ramps overnight?


I'm just never comfortable leaving anything on ramps unattended for a long period of time. I trust them and all,but I just feel you can never be too cautious and careful.

 

[FCD]

I usually drive the car , then wait for abour 45 minutes and drain it

 

[hatt]

I'd for sure drive it around to get it hot. Over 4-5 months of sitting a lot of stuff has fell out of suspension that needs to be mixed back up so you can drain it out. Look in the bottom of a jug that's been sitting with used oil if you don't believe me.

 

[Lyman]

I always at least run around the block to get everything back in suspension before draining.

 

[AuthorEditor]

In the future I would recommend doing the oil change just before you store it, then it is ready to go in the spring with fresh oil and filter and no need to think about it. Better to store it with the clean oil. I like to drive it a around a little after the oil change to make sure the clean, fresh oil is well circulated, then put the car up for storage.

 

[NormanBuntz]

Having a properly maintained car sit for 4-5 months is nothing. I'm sure you were using a battery tender and fuel stabilizer. This is done with classic cars all of the time. For me, I'd run it, then drain it.