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Topic: Engine oil color (Read 523 times) previous topic - next topic

Engine oil color

3,000 miles on my '98 U295 since engine oil and filters were changed when I bought it. Checked the oil level today and was surprised at the color. Black. Is it supposed to be the same color that went in? Just finished changing the hydraulic fluid and filters with the same Delo 15W-40, so I know what that looks like.
1998 U295 36' No slides
Towing 2018 Jeep Wrangler
Previous rigs:
  1995 26' Fleetwood Flair
  1998 34' Fleetwood Bounder
  1997 40' Bluebird BMC
  1999 24' Winnebago Minnie Class C

Re: Engine oil color

Reply #1
No problem. Diesels do turn the oil black.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Engine oil color

Reply #2
No problem. Diesels do turn the oil black.
Oh, thank you, thank you. My first diesel, and I was hoping that was the answer, but it had me concerned!
1998 U295 36' No slides
Towing 2018 Jeep Wrangler
Previous rigs:
  1995 26' Fleetwood Flair
  1998 34' Fleetwood Bounder
  1997 40' Bluebird BMC
  1999 24' Winnebago Minnie Class C

Re: Engine oil color

Reply #3
I'm willing to bet you are not the first new owners to be shocked by the rapid color change of the engine oil.  Our coach was also our first diesel engine (8 years ago) and I had the exact same reaction.

On the bright side:  makes it much easier to see the oil level on the dip stick!  :thumbsup:
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Engine oil color

Reply #4
Oh, thank you, thank you. My first diesel, and I was hoping that was the answer, but it had me concerned!
Diesels are veritable lamp black factories.  The particles are too fine to be removed by the oil filter, i.e. too small to be harmful.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: Engine oil color

Reply #5
Dan & Annie,

If you guys are the inquisitive or scientific minded types, and wish to be more informed about what is happening inside your engine, you might consider getting the oil analyzed at your next change.  There are several companies offering this service.  Search "oil analysis" on the Forum for many opinions.  See the thread below to get you started:

Oil Analysis, Many of You Do This?
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Engine oil color

Reply #6
Most of the black is just carbon. Not harmful.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Engine oil color

Reply #7
I change my Cat 3126 at 4K miles. It is just starting to get black.

I realize black is normal, but I believe my ring problem was do to extended oil changes. Carbon behind the rings on the 3126 Cat is deadly. Oil is cheap.

Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Engine oil color

Reply #8
A last thought to U.  If it is gray or brown, "milky". U are getting coolant into it.  Pray for something simple but get it to a shop familiar with diesels at once,  not to be trifled with. 
Bill, Tricia, Sassy  Mostly poodle. Maybe
It,s. 5 o clock somewhere,  ?
MoHo has 3 happy days,  Buy, everything works, sell.
  Hopefully the rest are pleasant days.

Pull 05 Jeep Liberty.

 

Re: Engine oil color

Reply #9
A last thought to U.  If it is gray or brown, "milky". U are getting coolant into it.  Pray for something simple but get it to a shop familiar with diesels at once,  not to be trifled with. 

And vs verses. I got diesel in the coolant. Cracked injector sleeve. Forutantly, it didn't get coolant in the fuel.

Diesel in the coolant you can't see, you only notice your coolant level going up, then smell it.

Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348