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Topic: 8.3 Cummins oil overfull (Read 638 times) previous topic - next topic

8.3 Cummins oil overfull

Looks like they filled my 8.3, Cummins engine 2 quarts over full. Should I be concerned?
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: 8.3 Cummins oil overfull

Reply #2 –
I had the same problem when I had the oil changed in Nacogdoches.  When I got home and checked the oil the next day and it was over full. I sent them an email and took my vacuum oil changer for the boat that goes through the dip stick and removed the 2 quarts.  I had used a coupon for the oil change so they were the ones that lost the cost of the two quarts and  I lost the time getting the oil back out.

I would get the extra oil removed.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: 8.3 Cummins oil overfull

Reply #3 –
How do you know it's 2 quarts?,On a 5 gallon system 2 quarts equates to about a third of a quart on a 5 quart car engine,I
would'nt give it a worry,it will run fine.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: 8.3 Cummins oil overfull

Reply #4 –
I wouldn't loose any sleep over it.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: 8.3 Cummins oil overfull

Reply #5 –
Old Cummins engines were open, overfill oil escapes the crankcase via a tube exiting at the bottom of the engine.  The oil shows up on the tow vehicle and makes a big mess.  But does no damage to the engine.

Re: 8.3 Cummins oil overfull

Reply #6 –
I had no issue when over filling 1/2 gal. on oil changes before finding out true capacity. Nothing even came out of the engine on those oil changes.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: 8.3 Cummins oil overfull

Reply #7 –
Previous owner of our 98 u295 it would coat the tow and rear of coach I've had good results no issues with 18 qts on last several oil changes
SLC12

Re: 8.3 Cummins oil overfull

Reply #8 –
Some have found dip stick needs calibrating due to not being accurate.  Postings on Forum about modifying the dip stick tube with a brass compression coupling.  Fully drain, fill with 6 gallons, adjust dipstick if not exactly correct after oil settles.

Re: 8.3 Cummins oil overfull

Reply #9 –
From a piece I wrote long ago:

CALIBRATING THE ENGINE OIL DIP STICK

We continue to see questions about oil "consumption" and oil on radiators and toads.  It seems to be universal across all brands of diesel engines.

THE NUMBER ONE CAUSE IS AN OVERFILLED CRANKCASE. CALIBRATING THE ENGINE OIL DIP STICK TO ENSURE THE CORRECT OIL LEVEL IN THE PAN "FIXES" OVER 90% OF THESE PROBLEMS.

If you "think" your engine has an oil consumption problem, you are seeing oil mist on your toad or you just want to verify that yours is correct; you need to verify that you are using the correct amount of oil. Note: the quantities listed INCLUDE the oil filter and is the total amount of oil you put in when changing oil and filter.

Now, CALIBRATE THE DIP STICK. Since the same engines/dip sticks are used in many different applications with different angles of installation, do not ASSUME that the dip stick is correctly marked. Calibration costs $0.

At the next oil change, drain oil, remove old filter (as usual). Then install the drain plug and new oil filter and add the engine's correct oil capacity LESS THE NUMBER OF QUARTS you want between the "ADD" and "FULL" marks (let's say 2 quarts). So for an engine with 20 quart capacity you would add 18 quarts. Run the engine a few minutes, shut off and wait until oil has descended into the pan (at least 30 minutes and an hour is safer). Pull the dip stick and use a file or dremel tool to mark the oil level "ADD". Add the remaining two quarts, let the oil settle in the pan, pull the dipstick and mark this the "FULL" mark.

In many/most cases, you will find that your engine "throws out" the access oil and then "consumption" settles down to next to nothing. Put in the correct amount and your "consumption" issues may go away.

This applies to all ages (including brand new) of motorhomes and boats with every brand of engine.

Also, when checking the oil level with the dipstick it is safest to do it in the morning after the oil has had all night to flow back to the pan.

Do not add oil until the level reaches the ADD mark.

Finally, make a sticker to affix near oil fill:  OIL CAPACITY INCLUDING FILTER: xx QUARTS.
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: 8.3 Cummins oil overfull

Reply #11 –
I have read your post several times in the past but never caught the advice "not to add oil" until add mark. That's new advice for me.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: 8.3 Cummins oil overfull

Reply #12 –
Quote from: Realmccoy –
I have read your post several times in the past but never caught the advice "not to add oil" until add mark. That's new advice for me.

Yes, many engines oil "seeks it own level".  When I first started, if the oil was two quarts low, I would add two quarts.  Thought I had an oil consumption issue.

At the recommendation of a Caterpillar service manager (would also apply to other engine brands) he suggested not adding oil until it got down the the "add mark" (yes, add mark of calibrated dip stick).  Once oil got down just over 2 quarts from full, no more consumption and far less oil on back of coach/toad.
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: 8.3 Cummins oil overfull

Reply #13 –
I have a feeling that mirrors my experience. Mine seems to want to live two quarts low. If I top it off it soon disappears and then holds steady. I have confirmed that my dipstick is accurate.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: 8.3 Cummins oil overfull

Reply #14 –
For most engines, the top mark on the dipstick is not the full mark. It is the maximum, do not exceed mark.
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: 8.3 Cummins oil overfull

Reply #15 –
When you pay others to do things,  wrong, inaccurate results followed me like the plague. Along with the plague came countless hours of worry and frustration. Life is just too short for all the added BS.

Started doing my own everything when just a very young man. On rare occasion have decided to allow others to have my $ in exchange for services...plague and frustration is always the outcome. I'll do for myself I guess till I can do no more. $, does not buy everything.
Mike in AL
2001 U295
8.3 ISC 350
Build 5918

Re: 8.3 Cummins oil overfull

Reply #16 –
I bought an electric pump and pulled 2 quarts out. I'll watch and see how the dipstick looks after driving and it has settled.
Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.