[C320-list] Mixing Oil Brands

[Warren Updike]

The American Petroleum Institute (API) maintains a set of standards for
engine oil. You will see their "donut" on the label of any proper engine oil
sold in the US.  The donut is a round figure with the SAE rating in the
middle and the oil category around the outside.  The current category for
low-sulfur diesel oil is "CJ-4."  Virtually any oil you'll find today on a
retail shelf labeled "C" will be suitable (CI, CF, Cj.)  However, as always,
follow the manufacturer's recommendations.  The newer high-compression,
low-emission, diesels may specify the more recent ratings.  

Our diesel engines are classed as off-road diesels. The sulfur standards for
commercial off-road diesel fuel are different than those for on-road
passenger fuel.  Taxes may be different, too.  Some marinas may offer the
off-road diesels; but, I'd hazard a guess and say that most on the
Chesapeake are getting the same fuel as gas stations.  For that reason, I
use a diesel lubricity additive to combat the low-sulfur content.

Off-road standards for oil changes are more frequent than for on-road.  On
our 19 year old Perkins, I change the oil after 50 hours of use.  This
generally gets us to August.  I then change it again at the end of the
season, of course changing the filter as well with each oil change.  In any
event, ALWAYS change the oil and filter before a lay-up.

Warren & Pattie Updike
1994 C320 #62 "Warr De Mar"


-----Original Message-----
From: resloat [mailto:resloat at comcast.net] 
Sent: Saturday, November 03, 2012 3:46 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] Mixing Oil Brands

Bruce-As long as you use a trusted brand of oil for a marine diesel there
should be no problem with draining warm engine oil through the dip stick to
get as much as possible out.  Then add your Rotella to the proper fill
level.  I don't think any marina asks the skipper what brand of oil was in
the engine if they do an oil change for the owner.  They don't worry about
oil compatibility issues with so little of the old oil left.  Spend time
getting the last bit of old oil out and if the engine oil is warm and there
should not be a lot of old oil left.  I find that if I get the engine oil
warmed up and use a vacuum drainage system the the total oil from the engine
and from the filter is essentially what the 3GM30F requires (2.6 liters in
the pan = 2.7 quarts + a little from the oil filter)  I generally use a
little over 3 quarts for a complete refill with filter change.

I have the Yanmar factory service manual.  It spends 7 pages on fuel and
lubricating oils.  Shell Rotella is one mentioned as recommended.  Most of
the others mentioned are brands I have not seen so I assume there are many
other lubricating oils with the same SAE classification as Rotella that are
OK.

Maybe the former owner had a log of maintenance and indicated oil changes
and what oil was used.  I keep one for all maintenance I do.  It is a good
practice and demonstrates care for the vessel.  It might even help at resale
time when the much larger boat purchase is allowed by my lovely spouse.

Bob Sloat
Savannah Hull 894 (2002)
----- Original Message -----
From: "Bruce Hunter" <swampcreek42 at yahoo.com>
To: <C320-List at Catalina320.com>
Sent: Friday, November 02, 2012 3:34 PM
Subject: [C320-list] Mixing Oil Brands


We just bought a 2000 Catalina (Hull 719) in Seprember. Sadly the time has 
wizzed by and we'll be pulling her for dry storage on November 16th. 
Tomorrow we will be bringing her down from Baltimore where we hid her from 
the storm (Protected floating docks are GREAT!) and the engine will be nice 
and hot. I want to change the oil but I don't know what the previous owner 
used. I am planning on using Shell Rottella 15W-40 since I use it in my 
truck diesel and I've read it works well in the 3GM30F as well. I know I 
won't be able to get all the old oil out and some will be left in the pan, 
I'm thinking I will change it tomorrow and then once more before pulling it 
to lessen any reaction of different oil brand chemical packages negatively 
reacting with one another. Any thoughts?

Bruce
Hull #719