Topic: grey oil in engine

[laser145]

So I've just started to mess around with my CB450.

This weekend I pulled the dipstick and noticed the oil is grey...looks like the oil from the rear end of my old quad after a weekend in the swamp

Does this indicate water in the engine?

Am I'm not going to be happy with the answers?

Thanks

[BobbyR]

Usually water looks whitish sort of like bad milk in coffee. Where would you expect the water to come from?

[laser145]

I was wondering where it would come from too.

I just got the bike, so I don't know the history. But I know I used to get water in the rear end of my 4 wheeler from riding underwater... I can't imagine the little 450 being ridden like that

I'll have to get a better look at it this weekend, it was getting dark when I saw it the other day...

[Amphibious]

oil is cheap.  when in doubt, change it!

[wdhewson]

Grey oil was often the color of the lead deposits from burning highly leaded fuels of decades past.  Lead is in the blowby, gets into the oil, and gets suspended in the oil by the detergents and dispersants in the ooil formulation.  However, it is unlikely that your oil is that old, but avgas is still leaded.  Was the PO accessing an airport?

Sadly, another source of grey is finely divided aluminum.  The means that something like an aluminum bearing is wearing catastrophically.

Change the oil and monitor things closely.

[TwoTired]

Pretty common in the winter months to get condensation inside the engine.  It usually looks like brown mayo.  Grey/muddy could be metal particles, though.  So, it is best if you provide an accurate description.

Air cooling fins are sized to dissipate enough heat in hot weather under power so it will survive.  It is therefore by far over-cooled in the winter months, making the water condensation difficult to vaporize on short trips.

If it is brown mayo, a good long 20-30 minute run on the freeway after reaching op temp should get rid of it.  You need to thoroughly heat (180F degrees or better) the oil for some duration to "boil" off the water inside.

If it is grey metal particles, it will probably get worse until the engine stops entirely.

[Hinomaru]

Good advice from the other members and If the "grey oil" problem persists, consider performing a spectro oil analysis test. There are laboratories such as Blackstone that can provide this service and they do motorcycles: 

http://www.blackstone-labs.com/

This type of spectro oil analysis was a regularly scheduled and standard engineering practice on shipboard main propulsion diesel and some smaller gas engines. I found it to be an excellent maintenance, troubleshooting and repair tool.

(note the shipyard worker in the lower right hand corner of the photo)

[Steve F]

Good advice from the other members and If the "grey oil" problem persists, consider performing a spectro oil analysis test. There are laboratories such as Blackstone that can provide this service and they do motorcycles: 

http://www.blackstone-labs.com/

This type of spectro oil analysis was a regularly scheduled and standard engineering practice on shipboard main propulsion diesel and some smaller gas engines. I found it to be an excellent maintenance, troubleshooting and repair tool.

(note the shipyard worker in the lower right hand corner of the photo)

Sooooo, how many quarts in THAT oil pan?    

[Hinomaru]

Steve F,

That's the smaller V10 engine in the photo and is made by Colt industries (model 4.2) and takes around 1,300 gallons for a oil & filter change per engine. When you have multiple engines that really adds up and oil analysis determined when an oil change was needed. 

The larger V12, V16 and V18 models take a bit more oil ...

[HedNut]

Oooooo Cool ASS BIG ENGINE!! I'd love to have a set of pistons from one of those for yard ornaments...perhaps along each side of the driveway with two old bikes welded in the wheelie stance perched on the front two.....oh yes.

Grey oil....myself...first I'd change it as I would initially suspect condesation in the cases.  Look for debris in the drained oil...dip your fingers in it and rub them tightly together to feel for grit.  If there's larger than normal/shards/sharp grit...I'd dig deeper.  Otherwise, filler' up and run it for a bit and check the oil frequently.  If she gets grey again quickly or you see "sparkles" in the new stuff....something is wearing...if not...it was a case of "Schweaty cases"

That's just my thought on er'
Cheers!

[Don R]

Does that engine have an oil sump in the bottom? If so, drop it and see what's in there. clean it up and re-assemble.

[lordmoonpie]

Oooooo Cool ASS BIG ENGINE!! I'd love to have a set of pistons from one of those for yard ornaments...perhaps along each side of the driveway with two old bikes welded in the wheelie stance perched on the front two.....oh yes.

My local shop that rechromes fork legs also does machining for large engines like this. I once asked the foreman what the huge alloy bucket was on a pallett, big enough for me to stand in it and not see out....a piston for a cruise liner! Rescpect...

[wdhewson]

Regarding big ship engines..........one old mariner told me about the big 2-stroke crosshead main propulsion ship engines.  To measure bore wear the piston was lowered to bottom dead center, then he climbed through the cylinder intake ports, stood on the piston and took measurement with a special micrometer.  Naturally the engine was "locked out" to prevent accidental starting when he was inside!

[HedNut]

That's tooooo cool.... i'd love to be mini for a little bit, and crawl thru the SOHC 750....just pretend I was a little poof of atomized unleaded.....  BRAAAAAP!  ahah

Cheers!

Any updates on the grey oil in your bike??