Oil question please

[dnewton3]

I've never had it happen to me, so I don't really have a point of reference.

I was envisioning this kind of in small scale; more so like the wax would fall out in very small pellets, granules, or something like that. Easily poured, etc. Small enough that they would easily travel into the crankcase via the typical oil drain-back holes in the heads, etc.

If it ends up as big globules, then I can understand the concern, and necessity for mixing back together in a pot rather than the crankcase. You'd have to first pour out the liquid base, then cut the container open and remove the solids, then put it all into a large vessel for heating/mixing. If it got to this stage, I'd probably just junk it for fear I'd not get it well mixed.


I've got some HDEO VPB that I left out in the barn last winter. Now I'm curious ... Will have to check it out when I get a chance.

 

[Shannow]

Please do report back.

Gelling was identified as a problem back some time (your and my lifetimes) when a particular rate of cooling caused the wax to start to crystalise THROUGH the bulk oil, and affecting it's ability to get through the pick-up to the oil pump...the couple of taxi fleets that had a failure in the PPD/VI combo wouldn't pump even at above freezing, and caused failures.

(My guess) is that there's be some stratification, and you probably want it all back together to be a complete oil.

 

[BrocLuno]

This phenomena is delta T slope related. It's the cooling rate that sets it in motion. Not the absolute coldest temp ...

And yes, it gets to big globs

 

[Shannow]

crystalisation will do that...not here with engine oil 'though.

 

[dnewton3]

Originally Posted By: BrocLuno
This phenomena is delta T slope related. It's the cooling rate that sets it in motion. Not the absolute coldest temp ...

And yes, it gets to big globs

Originally Posted By: Shannow
crystalisation will do that...not here with engine oil 'though.



Interesting; had not occured to me.

Do we know if additive-drop-out happens in the crankcase? My Dmax truck, and my Kubota, both sit in the same barn that holds the oil stash.

I suspect (have no ability to prove) that it's likely a function of many things including the dT slope, min temp reached, the time at rest, the % of use (virgin vs used), etc???

 

[BrocLuno]

Shannow can point you to a couple of professional papers that look at this in detail.

Your diesels sitting in that barn might be in jeopardy ... One reason for block heaters or pan heaters was to keep the oil from doing this.

It ain't the add pak. It's the actual oil. And when it happens, it blocks the oil pump intake screen, so no oil pressure ...