Deep Cycle batteries not recommended for cold cranking of an engine. However, with second jump starting battery, juice is not the problem. Also doubt that starter is causing the "no start" problem. It does not take high speed turnover to start a diesel. Repeated cranking w/o time significant pauses for starter heat dissipation will ultimately buen up the starter.

1. Confirm filter connections are tight, air may be entering fuel system.
2. Bleed each injector line and confirm delivery of fuel both w/ hand pump and system pump. If fuel delivery is confirmed, it is likely that the valves were improperly adjusted preventing adequate compression.

Running before alterations (filters, adjustments) but not afterwards points to problem being caused by alterations.

__________________
Mike

82 240D 97K Original (Sweet)
96 Ford F350 CrewCab Dually,7.3 PowerStroke,144K
(a real workhorse, does anything I need)
04 VW Jetta GLS TDI, 33K (50 mpg & it's quick)
Notice a trend? All diesels

63 Chevy II Nova Convertible (wife's) awaiting restoration - Well everyboby has a little gas every once in awhile