T&T: 120 oil charge

[C. Marin Faure]

 >I think I've heard Bob Smith state that the full oil charge is 11  
quarts.
Not the published 12.


The times I have talked to American Diesel about our FL120s over the  
last eleven years they have always told me the amount to put in the  
sump is 12 quarts per the manual.  I've never heard American Diesel  
say anything about 11 quarts in the sump and one for the oil filter,  
or 11 quarts total.  SInce the oil filter sits upside down on the  
stock FL120, you can't prefill it anyway, so if you put 12 in you're  
going to end up with "eleven in the engine and one in the filter" as  
soon as you start the engine.

The manual says 12 quarts, our very experienced diesel shop says 12  
quarts, and everyone on the GB owners forum including people who have  
been maintaining, restoring, and servicing GBs preofessionally for  
decades has said 12 quarts when the subject has come up.  We've  
always used 12 quarts and have not had any problems (that we know of)  
from this.  The engines use perhaps half a quart at most in 100-150  
hours, they don't blow any excess oil out of anything, so 12 quarts  
seems like the right amount to put in.

Where the number "eleven" has come up is in the suggestion that when  
it's time to add the oil back in during an oil change, put in ten or  
eleven quarts, let it settle, mark the dipstick, and then add the  
last quart or two and mark the dipstick.  This will give you a better  
idea of how much oil the engine is using, if it's using any.

I suppose if your engines are mounted at a fairly extreme angle it  
might make sense to put in less than 12 quarts to keep the rear oil  
seal from sitting immersed in oil.  But this would be on an  
individual boat basis.


____________________
C. Marin Faure
GB36-403 "La Perouse"
Bellingham, Washington