Changing oil cold

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David R

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I am a life long mechanic. I change the oil in my bike when its hot. I fill the filter, Upon restart, it rattles and clangs until oil pressure is up.

If I do it cold, I hear nothing different than a regular cold start. (no noise)
Doing it this way from now on.

There has to be a chain and tensioner in there making most of the noise.
David
 
I have always thought the "drain when hot" is worth about 30ml more of oil.... better off chainging it a week earlier if that is what worries one.....

Hot is probally more important if one wants to do things quickly.... and get the vehicle off the hoist and the next one on......
 
A quick check on the internet produced this bit of
info. It also confirms what I was told when I started
doing my own servicing.

Most Oil Experts Say It's Better To Drain The Oil When It's Hot Instead Of When It's Cold, For Several Reasons:​

  • Oil viscosity is thinner when it's hot, so it drains more quickly and completely out of the engine than when it's cold.
  • On a hot engine, contaminants are more likely to remain suspended in the oil than when the oil is cold, increasing the chances they'll be expelled from the engine during the draining process.
  • Today's high-tech OHC engines hold oil in a lot more places compared to old-school motors, so it's got to be warm (and thin) to escape from all those upper-end crevices.
Point 2 is my main reason for doing an oil change when hot.
 
I always warm up my engines prior to an oil change for the above mentioned reasons. Normally I run the engine at idle for 15 minutes, let it rest for about five and then unscrew the drain plug. Been doing this for ages and never had an issue.
 
*****************************************
  • Oil viscosity is thinner when it's hot, so it drains more quickly and completely out of the engine than when it's cold.
  • On a hot engine, contaminants are more likely to remain suspended in the oil than when the oil is cold, increasing the chances they'll be expelled from the engine during the draining process.
  • Today's high-tech OHC engines hold oil in a lot more places compared to old-school motors, so it's got to be warm (and thin) to escape from all those upper-end crevices
  • *********************************************

All those points are not worth the RATTLE it makes on startup.
Yall do as you wish.

If you change the oil when its supposed, it will be fine even if a drop or 50 stay in the engine. You could leave the plug out longer, but I am not that anal. Its just a motor and oil.

It gets a fresh start with 4 quarts or liters of clean oil, a new filter.

Screw what the internet says. :)

David
 
David R said:
*****************************************
  • Oil viscosity is thinner when it's hot, so it drains more quickly and completely out of the engine than when it's cold.
  • On a hot engine, contaminants are more likely to remain suspended in the oil than when the oil is cold, increasing the chances they'll be expelled from the engine during the draining process.
  • Today's high-tech OHC engines hold oil in a lot more places compared to old-school motors, so it's got to be warm (and thin) to escape from all those upper-end crevices
  • *********************************************

All those points are not worth the RATTLE it makes on startup.
Yall do as you wish.

If you change the oil when its supposed, it will be fine even if a drop or 50 stay in the engine. You could leave the plug out longer, but I am not that anal. Its just a motor and oil.

It gets a fresh start with 4 quarts or liters of clean oil, a new filter.

Screw what the internet says. :)

David
Click to expand...
Fair enough, each to their own tbh. I much prefer to change the oil whilst it is hot. I have been doing this for ages and I like to think it works best for my anal mind. When the oil is warmer it should flow out easier and completely but that is the theory. I specially do this on my boat since I don’t have a drain plug on the engines therefore I need to use a vacuum to suck the oil out and definitely it works best when the oil is hot and thinner. 👊👊👊👊
 
I never change my oil hot.

I change oil cold, first thing in the morning. After the car/motorcycle has been sitting all night long. The next morning, I crack open the drain plug and let the oil drain out until the dripping interval is so long, it's meaningless.

Is all-night long enough for oil to drain from oil channels into the oil pan???

My question is rhetorical and sarcastic.

Been changing oil for over 20 years now on my own vehicles. I HATE changing hot oil!

Mike
 
I'd expect changing hot and recently circulated oil would also include more suspended particles and viscosity variances, before they settle out.
Sounds like cheap insurance and best way to get best long-term performance from the engine with the least interruptive maintenance schedule.
 
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The last of the 3 bullet points makes no sense..... to me.... (if cold... those spots have already drained to the sump on the last cool down cycle anyhow.... unless on the last run cycle was really short).... but... I always drain mine warm..... not hot (ouch) or cold.....

My best advice is to just make it one long drawn out drama.... so wife leaves you be in the garage for longer.....
 
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David R said:
*****************************************
  • Oil viscosity is thinner when it's hot, so it drains more quickly and completely out of the engine than when it's cold.
  • On a hot engine, contaminants are more likely to remain suspended in the oil than when the oil is cold, increasing the chances they'll be expelled from the engine during the draining process.
  • Today's high-tech OHC engines hold oil in a lot more places compared to old-school motors, so it's got to be warm (and thin) to escape from all those upper-end crevices
  • *********************************************

All those points are not worth the RATTLE it makes on startup.
Yall do as you wish.

If you change the oil when its supposed, it will be fine even if a drop or 50 stay in the engine. You could leave the plug out longer, but I am not that anal. Its just a motor and oil.

It gets a fresh start with 4 quarts or liters of clean oil, a new filter.

Screw what the internet says. :)

David
Click to expand...
AH come on now, we all know that if its on the internet it must be true! ROFLMAO! Also throw in this point Synthetic, is always much thinner, i.e. 15-50? It doesn't even pour like the Conventional oil. I agree hot or cold, I don't care, as long as its done on schedule, it will be fine TO EACH THEIR OWN.
 
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