I am a faculty member in an engineering department and I tend to defer a lot of 240 maintenance until the breaks between the semesters. In a week or so I need to begin the following jobs spread over four different 244s:

- Two AW70 tranny swaps (along with external seal and tailshaft bushing replacement).
- Three rear main seal replacements.
- One blower motor replacement.
- One heater control valve replacement.
- One rear suspension overhaul.
- Two front suspension overhauls (new bushings, tie rod ends, ball joints, shocks, and wheel bearings).
- Miscellaneous aesthetic work.
- In-tank prepump replacement.
- Intermittent signal from rear speedo/anitlock break pickup.

Big ambitions, huh? Re the blower motor replacement, is there anything I can use to clean out the heater core as a preventative maintenance measure? The current heater works perfectly and I'm simply not wealthy enough to preemptively replace everything that might eventually fail.

Thanks.