ever notice how OPE oil turns grey first?

[meep]

In my vehicles, the oil starts amber, moves towards brown, then black.

On the nicer OPE engines I've maintained, honda and subaru mostly, some over-loved tecumsehs, it does the same.

My wife is borrowing a mower (flat head briggs), oil was on the low side and was grey. I changed in rotella 15-40.

On the "roadside find" MTD "white" engine (pushrod OHV), I posted about recently, same thing.

My guess is fuel dilution or blow-by products being worse in the engines, but it's just a guess.

Why grey?

Mike

 

[The_Jeff]

I always figured it was metal shavings/ casting sand. The first change is sparkly.

 

[greenaccord02]

Aluminum

 

[meep]

are you saying your AL-blocked accord, camry, do the same?

 

[Craig in Canada]

Originally Posted By: meep
are you saying your AL-blocked accord, camry, do the same?


A lot of road vehicles still have iron sleeves, despite the rest of the block being Al. This is not the case with average Al block OPE. This means cylinder bore wear in OPE will be Al while it would be Fe in road cars.

Yes, there are always exceptions, that's why I use words like "a lot".

 

[javacontour]

Road vehicles typically have oil filters, so any glitter laced items probably end up in the filter.

OPE is typically splash lubricated and few have pressurized systems with filters.

 

[greenaccord02]

Originally Posted By: meep
are you saying your AL-blocked accord, camry, do the same?


No. They get their oil changed regularly, it's never low, and there are some subtle engineering differences from aluminum blocked OPE and a car engine. The question was what makes the oil grey, the answer was aluminum from wear.

 

[Bror Jace]

I think a lot of it is aluminum ... but not just wear bits (which are visible, shiny sparkles). As aluminum becomes oxidized, it turns grey/white. I think that may be a factor in play here.

Also, moisture in the oil will turn it a milky white ... which I think is also a possible contributing factor. Oil that has been in OPE for years probably has all of the above issues.

 

[severach]

OPE with pressurized oil systems and filters suffer from the same problem. I suspect the problem is simple. People just don't change oil on OPE engines and that's what oil looks like when run way too long. I've seen it in car engines after a 50,000+ mile OCI. Leaving in the factory fill only makes it worse. Who changes their OPE oil after the first 10 hours of operation? For a car that would be the 5*55=550 mile mark.

The OPE industry hasn't drummed into owners' heads that the oil needs to be changed. Where the Iffy Lube for my lawn tractor?

 

[meep]

Interesting thoughts about iron liners. I peeked into my eu2000 this weekend, which has some hard hours on syntec 10-30. it was amber. I think it's an AL cylinder, BUT, it gets annual changes. My older GC series honda was the same, amber, but with grey sparkles (not a flame!) when I used M1 in it. The robin-subaru motor was always amber, but it did have an iron liner. If it IS liner dependent, then there's more to it than just that, maybe it's more an OCI thing?

The 2 "grey" engines I observed didn't have any sparkle--- was just a grey color.

Hmm.

 

[boraticus]

I've never seen grey oil in any ope I have. Dark amber or black. I'm going with the aluminum/oxidization theory. Makes sense to me.

 

[Bror Jace]

I have seen grey oil in two types on engines ... OPE that have been horribly neglected for years ... and my brother's 2-stroke dirt bike (Honda CR250). But the latter's engine oil was also used by the transmission which would really chew it up.

It could be the grey is just oil sparklies (aluminum, mostly) that have been regrounded hundreds of times until they are so fine that the human eye cannot see a "sparkle."

Gotta figure at least some moisture and other contamination is in there as well to give it that "creamy" look.

 

[meep]

well, here ya go...

So i returned the borrowed mower and emailed the guy saying I returned it on his driveway with fresh gas, stabil, sharped blade and an oil change. he said, "why?" said he never changed the oil, just added it whenever he thought about it. old oil-- oxidation, pasty Al, etc...

Poor little briggs. maybe I just doubled it's life...

 

[boraticus]

Nothing like appreciation for a good deed!

With some people, the lights never come on. Just the way it is.

 

[javacontour]

Originally Posted By: meep
well, here ya go...

So i returned the borrowed mower and emailed the guy saying I returned it on his driveway with fresh gas, stabil, sharped blade and an oil change. he said, "why?" said he never changed the oil, just added it whenever he thought about it. old oil-- oxidation, pasty Al, etc...

Poor little briggs. maybe I just doubled it's life...



Now if it breaks in the next 10-15 years, it will be your fault. No good deed goes unpunished.