Cold Oil Change?

[The Rocketman]

I apologize in advance if this topic has been beaten to death in the past. For 36 years I've always changed my oil hot.

Since my bikes have been sitting dormant in the garage for almost 6 months since Thanksgiving, would you still recommend warming up the bikes before changing the oil, considering it’s had ample time to all drain down from the oil coolers?

Thanks,

Larry

 

[dirtrider]

14 minutes ago, The Rocketman said:

I apologize in advance if this topic has been beaten to death in the past. For 36 years I've always changed my oil hot.

Since my bikes have been sitting dormant in the garage for almost 6 months since Thanksgiving, would you still recommend warming up the bikes before changing the oil, considering it’s had ample time to all drain down from the oil coolers?

Thanks,

Larry

 

 

 

Morning Larry

 

It's kind of a double edged sword.

 

The up-side is that the oil has obviously drained back (as much as it can) but there is still some oil trapped in areas that can't drain back.

 

Now the downside-- all the gunk & junk that has settled into the bottom of the oil sump over storage time   will not drain out with a cold oil change. So that will then mix in with the fresh oil.

 

Cold oil will also take a day or two to ALL drain out of the lower engine area (oil clinging below existing oil level).

 

So pick your poison-- would you rather drain cold oil with a gunk & junk left remaining in the bottom of the oil sump, or  would you prefer to drain (relatively clean oil out that that has drained back over time?).

 

The other slight issue (with storage length cold oil change)  is that with the oil-drained-back then the engine parts that have drained back over storage have little to no lubrication until the engine is running for a few seconds  and building oil pressure. Now add in a fresh oil filter & that after-start run time without oil flow is even longer. (even if you prefill the oil filter it will still take slightly longer to build after-start oil pressure).

 

   

 

 

[The Rocketman]

Looks like a warm oil change is the way to go, again.

[Joe Coastie]

It's a reason to go for a ride. Warm it up.

[Skywagon]

I start most sentences with do what DR says......If it were me, I would ride it for about 45 minutes and bring it up to temp then drain.  Why?  After sitting that long there is no doubt there is condensation formed in places the oil hasn't been circulated through since you parked it.  I would not want that condensation in my new oil....  

[eddd]

I've done both.  Sometimes it is a pain or impractical to warm things up.  Under circumstances like yours I would say it would be impossible to find any real evidence to link any damage or shorten engine life to a cool oil change.

[The Rocketman]

My thoughts were that all the oil & residue would be so low in the sump after all these months, why recirculate the crap. But DR makes a point that there's garbage below that might not fully drain, and I'd rather not have that floating around and mixing with the new oil. Its really no biggie, except I have to do 3 bikes, and I guess they and I could all use some fresh air time.

[dirtrider]

4 minutes ago, The Rocketman said:

My thoughts were that all the oil & residue would be so low in the sump after all these months, why recirculate the crap. But DR makes a point that there's garbage below that might not fully drain, and I'd rather not have that floating around and mixing with the new oil. Its really no biggie, except I have to do 3 bikes, and I guess they and I could all use some fresh air time.

 

Afternoon Larry

 

As a common sense controller___

 

Just about every newer service manual that I have, & that includes  (many different makes & models including tractors,  automobiles, 4 wheelers, even my generators have a sentence in the first paragraph in the oil change section that says something like (warm engine to operating temperature  before changing oil),  or (warm engine oil to operating temperature before changing). It's definitely in the BMW motorcycle service manuals.

 

 

 

 

 

 

[The Rocketman]

If its in the "DR manual" its good enough for me. Thanks again.

[dirtrider]

1 hour ago, The Rocketman said:

If its in the "DR manual" its good enough for me. Thanks again.

 

Afternoon Larry

 

Actually my internal manual is slightly different. I almost always change my oil & filter before winter storage (especially on equipment that has been used in the very cold fall just before winter).

 

Most motorcycles have exposed oil sumps (some more the others) so in cold damp weather riding  the oil has a very difficult time reaching a high enough temperature to purge the moisture out of the crankcase. (BMW boxer riders look at that darn oil temp gauge & figure 'OK' the oil has heated up, they don't realize that it isn't reading oil sump temperature but is just reading the oil temp of the cooling oil before it reaches the oil cooler)

 

Storing any engine with moisture & acids in the oil is a good way to etch a bearing journal.

 

Over the years I have seen a number etched bearing journals due to storage + moisture + acidic oil.

 

Same reason that I could never understand why a motorcycle rider would start their engines in the cold of winter as they will almost never  get hot enough running statically in cold weather to get the moisture out of the oil.  

 

When I was a young kid (many/many moons ago) I worked a winter on a dairy farm. I used an old (fairly new then) John Deere B with a manure loader to clean the barn & remove piles of XXXX shoveled out of the stalls).   

Part of my job was to drain the tractor's crankcase of moister (water) buildup every week or two. I would drain at least 2-3 quarts  of water out  that tractor's oil sump at almost every draining.

Now that was a worst case as a dairy barn with cows in it has a winter humidity level of darn near 100%-- But that old JD  tractor also had an actual crankcase vent pump to try to keep the crankcase purged.

 

 

[Dave Parry]

I  say definitely warm it up!