Hello Mr. Tore,
I change the Oil and filter on my car every 3,000 miles... Do you remember how often they changed the 2 lube oil filters on the Type VII C diesel engines?
Regards,
Don_
Don.
I don`t think you can compare a disposable car luboil filter with a complex large marine diesel luboil filter. Normally a marine luboil cleaninginstallation have sentrifuges. Such installation add weigth and require space which make it difficult to accommodate in a submarine. When the VIIC/41 was introduced weight become a problem as the increased diving depth required a heavier steel plating and every possible excessive weight had to be removed. The lubeoil sentrifuge and the reversing of the diesel engines were sacrificed and a large sofisticated lubeoilfilter was installed. Such a filter do not have a disposable insert as on the car engines, but are of a "selfcleaning" type, either by means of a reversible oilflow,back wash type, flushing the contaminations to the dirty oil tank or a "knife filter" which has a long rotary steel knife ( brush) along steel steel filter insert which skims off the contamination dropping it to the bottom of the filter where it is drained to the dirty oil tank. I guess the VIIC had the first type for the lubeoil- and for the fuel the "knife" type filter after the fuelfilters. In your text showing the filters on the front of the engines it seems to me you are mixing up the double fuelfilters with the lubeoil filters. The VIIC lubeoil filters are single, much larger, some 400 mm diameter and 600mm long, and not generally visible, placed under the floorplating forward engineroom in the area where the sentrifuges used to be.
As to the fuelfilters attached on the front , you have a port and starboard fuel knifefilter placed behind the hp fuelinjection pumps as shown on the image below.
The drawback with lubeoilfilters is watercontamination, quite common on a submarine. You had to rely on a certain settling in the systemtank, however if the lubeoil emulsified you are lost, it happened once in three year with me.
Otherwise I believe the text is OK.
Tore