If i mark the pump prior to loosening any nuts & dont try turning the engine from the current position it is in, won't this same position be the same when i go to reinstall
the pump? Would i still need the locking tool for the flywheel? Would i not have the same timing as at removal?
I take it that you are going to send the pump for service/repair. If any parts are changed that may inflict on timing, you must re-time the pump at installation, and would need the tool that 'locks' the fly-wheel in TDC position.
the indicator guage should read as per the
adjustment data in service bulletin. What is this data? I don't have this? Again i ask if this can be achieved by marking pump prior to removing?
From time to time engine producers may change data, even those originally stated in the workshop manual. The do it by issuing 'service bulletins' to dealers. You may have to check with an authorized dealer to get the latest data. If the workshop checking the pump is an authorized Bosch shop, they should have the data as well.
The manual also states pump can be late or early, can you explain the actions of both of these instances?
A 'worn' pump may be 'late' in timing, often noticed by heavy smoking.
A defect in timing mechanism may change to timing to 'early'. This however is often noticed by increased 'diesel-knock' in the engine.
In both cases the pump needs to be run in test bench and correctly adjusted/repaired before being re-timed on the engine. I have however quite some times 'adjusted' pumps without both tool and setting info 'by ear' in emergency cases. I'll not recommend it unless you are a bit experienced.
If you decide to get a mech doing the timing and installation job, be sure he has both the needed tools and the latest data before starting. If not, you might as well do it yourself!!