Reply
 
Thread Tools Display Modes
 
Old 07-07-2016, 11:33 AM   #1
Veteran Member
 
City: Rock Island, IL
Country: USA
Join Date: May 2013
Posts: 37
Dirty Oil After Oil Change?

This is an odd question but here goes. Last winter I had the oil changed in my Cummins 5.9TA's but was not present when this was done. When I got back to the boat 2 months later I checked the oil and the oil in the port engine looked clean while the oil in the starboard engine was dark. I mentioned this to the mechanic and he said it was due to the old oil still being in the oil tube and this was what was showing on the dipstick. We have only ran the boat a few times since for only a couple hours of run time but when checking the oil a couple of weeks ago the oil in the port engine still looks relatively clean and the oil in the SB engine still looks dark. I have the oil change system but not sure if this has anything to do with it. Did the mechanic only do one engine? He did get side tracked in the middle of winterizing it and maybe forgot what he was doing. Has anyone encountered the dark oil in one engine after an oil change? Thanks!!
__________________
Advertisement

sammy999 is offline   Reply With Quote
Old 07-07-2016, 11:44 AM   #2
Senior Member
 
Max Simmons's Avatar
 
City: Everett, WA
Vessel Model: Ocean Alexander 38'
Join Date: Oct 2007
Posts: 493
It would be interesting to get an oil analysis and compare the two.
__________________

Max Simmons is offline   Reply With Quote
Old 07-07-2016, 12:32 PM   #3
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,322
Sounds fishy to me. Unless the filters were not changed at the same time as the oil.
Capt.Bill11 is offline   Reply With Quote
Old 07-07-2016, 02:09 PM   #4
Dauntless Award
 
Wxx3's Avatar
 
City: New York, NY
Country: USA
Vessel Name: Dauntless
Vessel Model: Kadey Krogen 42 - 148
Join Date: Jan 2013
Posts: 2,061
As CB says, fishy, very fishy.
Now, my oil when changed looks new until the engine runs a few hours and then looks dark, very dark.
But if the engine was not run, ...

Lesson learned, save the money and change the oil yourself.

Also, once you don't trust someone, don't go back again, if you do, it's on you, not them.
__________________
M/Y Dauntless, New York
a Kadey Krogen 42 Currently https://share.delorme.com/dauntless
Blog: https://dauntlessatsea.com
Find us: https://share.delorme.com/dauntless
Wxx3 is online now   Reply With Quote
Old 07-07-2016, 02:54 PM   #5
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 5,924
Sammy

Is this a new to you boat and the first oil change? How many gallons of new oil did you get charged for? Was a new filter installed? It is not easy to extract the last gallon on some engines, how was old oil removed? Is this a mechanic to be trusted?

On my engines there is always some residual oil left after pumping it out. I add a half gallon of new to dilute remaining old oil and pump it out again. Maybe the residual on one engine was more than the other.
sunchaser is offline   Reply With Quote
Old 07-08-2016, 06:27 AM   #6
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 15,604
I have found its very common and mostly a difference in on engine filter stules.

My 8V71 and series 50 will show black after an oil & filter change and a 5 min run to look for leaks.

The older 6-71 has a bypass filter , in WWII books its called a "colour filter" and after change the oil doesn't even get as tan as car oil for 50 hours.
FF is offline   Reply With Quote
Old 07-08-2016, 09:45 AM   #7
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,296
For 25bucks you can sample the oil.

For 60bucks you can change it again.
Ski in NC is online now   Reply With Quote
Old 07-08-2016, 09:50 AM   #8
Senior Member
 
Jetstream's Avatar
 
City: Brisbane
Country: Australia
Vessel Name: Searenity
Vessel Model: Meridian 459
Join Date: Jul 2015
Posts: 158
We have two 6bta5.9 and I changed the oil and filters on both recently. The oil colour was nice and clean on both when first changed and is starting to go dark with use at about the same rate. As for the old oil still being in the dip stick tube this is rubbish. My guess is he only change the oil in one.
Jetstream is offline   Reply With Quote
Old 07-08-2016, 09:55 AM   #9
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,322
Quote:
Originally Posted by FF View Post
I have found its very common and mostly a difference in on engine filter stules.
You've found it common that when the oil is changed in a pair of engines in the same boat one will show clean light colored oil on the dip stick after the change and the other engine will show dirty or dark oil on the stick?
Capt.Bill11 is offline   Reply With Quote
Old 07-08-2016, 10:05 AM   #10
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,322
Quote:
Originally Posted by FF View Post
I have found its very common and mostly a difference in on engine filter stules.
You've found it common that when the oil is changed in a pair of engines in the same boat one will show clean light colored oil on the dip stick after the change and the other engine will show dirty or dark oil on the stick?
Capt.Bill11 is offline   Reply With Quote
Old 07-08-2016, 10:11 AM   #11
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 3,296
Seen this before. Can be one engine held more old oil than the other.

Can be the "dirty" engine was running at a higher load, causing its oil to load up with soot. Then with change, the really dirty remaining oil turned the new oil dark.

I'd just change it again.
Ski in NC is online now   Reply With Quote
Old 07-08-2016, 10:13 AM   #12
Guru
 
ancora's Avatar
 
Join Date: Dec 2007
Posts: 3,433
I have always changed my own oil and never had one engine show "dark." I smell a rat...
ancora is offline   Reply With Quote
Old 07-08-2016, 11:36 AM   #13
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 14,272
With Ski on this one...I have run a bunch of twin engine boats where the dipsticks, cooler setups, even the list of the boat may have contributed to more dirty oil in one than the other.

I have changed my own oil after switching positions of the remote filter and shortening the oil lines...now it stays cleaner longer. Before, it was black by the end of the first day.
psneeld is offline   Reply With Quote
Old 07-08-2016, 04:19 PM   #14
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,322
I'll take you guys word for it.

While I've seen the fresh oil in an engine/s get "dirty" shortly after a change after a couple hours of running, I've never seen the oil in one engine of a pair not look dirty while the other did after the same run hours.
Capt.Bill11 is offline   Reply With Quote
Old 07-08-2016, 08:00 PM   #15
Veteran Member
 
City: Rock Island, IL
Country: USA
Join Date: May 2013
Posts: 37
thank you all for the replies. I will change the oil in both engines and go from there.
sammy999 is offline   Reply With Quote
Old 07-08-2016, 08:10 PM   #16
Guru
 
BruceK's Avatar
 
Join Date: Oct 2011
Posts: 6,901
I used to DIY the oil changes, sucking out the old stuff via the L120 dipstick hole. Last time I had the marina mechanic do it. He uses a vacuum pump, one of those tall tubular things, and he leaves it connected overnight. He got much more old oil out than I ever did judging from how clean the fresh oil was, and stayed, for quite some hours.
__________________
BruceK
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Old 07-09-2016, 08:29 AM   #17
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 15,604
"He uses a vacuum pump, one of those tall tubular things, and he leaves it connected overnight. He got much more old oil out than I ever did"

Allowing the engine oil to drain overnight would not be mu choice.

On a normal oil change the passages and OIL PUMP are still full of (old dirty) oil.

With an overnight drain you are assured of a real dry start for the first few seconds of operation, the usual drain removal method gives no dry start , but does leave a cup or two of "old dirty" oil.

For me a cup of old oil in 7 gallons of fresh is no big deal.
FF is offline   Reply With Quote
Old 07-09-2016, 08:32 AM   #18
Senior Member
 
City: Freeport Tx
Country: Us
Join Date: Nov 2014
Posts: 116
I have had this happen. On my 692s it was every time looked like you had not changed the oil.
Pure pleasure is online now   Reply With Quote
Old 07-09-2016, 09:30 AM   #19
Guru
 
Capt.Bill11's Avatar
 
City: Sarasota/Ft. Lauderdale
Country: USA
Join Date: Apr 2014
Posts: 5,322
Quote:
Originally Posted by Pure pleasure View Post
I have had this happen. On my 692s it was every time looked like you had not changed the oil.
In both engines or one looked clean and one looked dirty after the change?
Capt.Bill11 is offline   Reply With Quote
Old 07-09-2016, 08:29 PM   #20
Guru
 
BruceK's Avatar
 
Join Date: Oct 2011
Posts: 6,901
Quote:
Originally Posted by FF View Post

...Allowing the engine oil to drain overnight would not be mu choice.
On a normal oil change the passages and OIL PUMP are still full of (old dirty) oil.
With an overnight drain you are assured of a real dry start for the first few seconds of operation, the usual drain removal method gives no dry start , but does leave a cup or two of "old dirty" oil.....
That`s a good thought.
__________________

__________________
BruceK
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 09:35 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012