oil changes when engine oil is room temp?

[edwardh1]

anyone ever done it over an engine life time or seen any tests of cold (room temp) oil changes?

my guess is its not much different in effect on the engine as hot oil changes.

 

[bigjl]

One thing that can certainly be certain is that every time the cold oil is drained it will take an awful lot longer and will not be as complete.

I personally think it would be detrimental to the engines long term well being to continually change oil when cold.

 

[Coprolite]

I don't think it would have a long term adverse effect on anything except for your spare time, waiting for everything to drain.

 

[Tzu]

I've only done it once when I had to have the head re-machined due to a burnt valve on my '91 Camry. It took a long time to drain, but at that point it was the least of my worries. The oil was diluted with gas due to no compression in that cylinder and having to drive it home for an hour like that. It also caused my catalyst convertor to glow a light orange. Draining it hot or atleast very warm does a much better job of getting suspended particles out and away. Probally doesn't hurt, but I would always do it hot.

 

[Garak]

Originally Posted By: Tzu
I've only done it once when I had to have the head re-machined due to a burnt valve on my '91 Camry.

About the only times I've ever done cold changes were in conjunction with engine work, too.

 

[brnmw]

Funny... I suppose it really depends on where you are from and just what does room temp. mean for you in your location? (I have never been to the Carolina's so I don't really know)
Being from South Texas it gets pretty hot down here so starting your car for about 5-10 min. max then do an oil change is really good enough to get your engine warmed up enough and get the oil nice and toasty. Being in the north I would imagine starting your car and having to wait 20-30 min. engine run time would be a pain, but I would say highly recommended. I would never do an oil change on a cold engine IMO. (Then again a Texas cool engine is not a Canadian cold engine either.)

 

[ARB1977]

When I was working on general aviation piston engines we used 15W50 aviation oil. Now in California on a cold engine it would take half of the day to completely drain. Most of the engines had drain valves. By the time you saw oil coming out it sometimes took 5 mins by the time we hooked up the hose.

For the most part these engines made it to TBO, which was about 2000 hours.

 

[Doog]

I have done both. Makes no difference unless it is Winter and below 40F. Then you have a long wait. Technically when oil is hot more of the combustion by products are suspended in the oil. But as a practice I change when warm.

 

[Kuato]

Originally Posted By: Doog
...Technically when oil is hot more of the combustion by products are suspended in the oil. But as a practice I change when warm.


Same here.

Warm oil flows out much more quickly....a huge advantage I learned about years ago when it was 0*F and I was lying on the ground waiting.

 

[TFB1]

Originally Posted By: Kuato
Originally Posted By: Doog
...Technically when oil is hot more of the combustion by products are suspended in the oil. But as a practice I change when warm.


Same here.

Warm oil flows out much more quickly....a huge advantage I learned about years ago when it was 0*F and I was lying on the ground waiting.


I doubt there is a problem draining cold but unless it's non-runnable I'll not drain oil when cold...

As far as cold weather, chances are about same as it reaching zero here that I'll change any oil in winter(twice in the last 140 years or so)... Would have to be a project that falls in my lap... The regular runners all get once a year, spring time changes...

 

[edwardh1]

I just wondered if there had ever been a test to see what the effect on engine wear was of draining at room temp. I dont like handling the hot filter and have started changing the filter cold and the oil later.

 

[Kuato]

Originally Posted By: edwardh1
I just wondered if there had ever been a test to see what the effect on engine wear was of draining at room temp. I dont like handling the hot filter and have started changing the filter cold and the oil later.


Changing immediately after turning the engine off does make it pretty hot.

I've actually started waiting between 15-30 minutes for things to cool down somewhat before I start the change.

FWIW, I would change the oil first and the filter later if you aren't doing it at the same time.