Oil change - Hot or cold engine

[98civex]

My car has been parked for a few days and I need to change the oil.

I'm wondering if I can drain the oil without first driving the car to warm it up.

It has been parked for a while so I'd imagine most of the oil has settled in the pan?

 

[HeX]

The benefits of changing warm oil is that its more likely for more of it to drain out whereas cold oil will stay thicker and stick inside a little more, but its not a drastic difference in amount anyways. You need to be more careful not to burn yourself if the engines been warmed up, but you could just let it run for 2 minutes before draining it so its just warm enough.

 

[98civex]

The benefits of changing warm oil is that its more likely for more of it to drain out whereas cold oil will stay thicker and stick inside a little more, but its not a drastic difference in amount anyways. You need to be more careful not to burn yourself if the engines been warmed up, but you could just let it run for 2 minutes before draining it so its just warm enough.

Cool. My car has been sitting for like 3 days so wouldn't most of it have drained to the pan by now?

 

[HeX]

Yes, but itll stick to the sides more when cold thus taking longer to drain. But again its not significant especially if the current oil in it isnt in dire need of replacement.

 

[Mur man]

ughh,
98civex... 473 messages and you're a new member???

All of your changeable oil is in the pan now.
There are places in the engine circulation system where some residual oil is present until circulation forces it to mix in with the new oil. I believe it's less than 1% as compared to the amount of replacement oil.
The only cheap way to (fanatically) clean out the old oil.....and double the cost and labor, follow these instructions;
1) Drain the old oil and install new filter,
2) add new oil and run the engine 30 minutes, then
3) drain the new oil out, change the filter again and add brand new oil again.

That's the best you can do without dismantling the entire system. Any mechanic will tell you it's not necessary to double flush the oil like this, since the 3month/3000 mile rule is enough to keep the proper viscosity of oil in the engine, which is why you need oil in the first place. Now If you have a bad piston ring and blue smoke coming out the exhaust then you need a mechanic.

 

[98civex]

So changed it with a cold engine.

When I removed the oil filter nothing dripped out. I'm guessing either a non-existent or bad anti-drain valve?

 

[HeX]

So changed it with a cold engine.

When I removed the oil filter nothing dripped out. I'm guessing either a non-existent or bad anti-drain valve?

Or you were just low on oil. It doesnt matter now since you replaced it so regularly monitor the oil level. What brand of filter is the old one?

 

[98civex]

Or you were just low on oil. It doesnt matter now since you replaced it so regularly monitor the oil level. What brand of filter is the old one?

 

[HeX]

I believe they're bulk-sold cheap filters for lube shops. They may be made by Purolator but if they were of top quality then they would just say Purolator. Read this article for what its worth. I feel it goes along the lines of typical lube shop mediocre quality bulk filters used for cost cutting.

http://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1790533

 

[98civex]

Makes sense I did go to a lube shop for my last oil change. Not only did they overfill the oil by a quart but when I just changed it I realized they stripped the drain plug threads a bit.

That link says they do have an anti drain back valve. Wonder why mine was pretty much empty then. My oil level was full before changing too