[C320-list] Mixing Oil Brands

[resloat]

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