For the owners of the cummins C8.3 (mechanical) engines, I came across this in the Bluebird Owners' forum:
Cummins C8.3 engine in BMC 37'. There are four filters you should be concerned about.
LF3000 - Lube filter which is your engine oil filter. Make sure you fill it with oil when replacing it.
There are 2 gaskets -- both should be lubricated with oil.
Fuel/Water Separator which in essence is your primary fuel filter. It's the one that's easy to get to
and is the larger of the two fuel filters. It is at the right rear of the coach mounted on the frame
rail. It has a drain on the bottom which you can open to drain out any accumulated water. Fill
with fuel and lube the gasket with oil before replacing it. There are several options for this filter:
The FS1242 and NAPA 533242 are designed for use with a clear plastic bowl at the bottom.
The FS1212 is designed without the clear plastic bowl. IE: If your coach has the clear plastic
bowl at the bottom you will need FS1242, or NAPA 533242. If your coach does not have the
clear plastic bowl you will need part number FS1212. I loaded pics of the two filters in the photo
FS1251 - This is the smaller of the two fuel filters. It is located high up on the passenger side of
the engine and is a real ***** to get to. The "special tool" used to get to it is called a long, greasy
arm. Be ready to jump in the shower whenever you finish replacing this one. Like the other fuel
filter, fill with fuel and lube the gasket with oil before replacing it.