Owner manual
Form # 147459  Issue 11/06 Web Rev_01 
108 
  MAINTENANCE/SERVICE 
Cab Air System 
RETURN AIR FILTERS
Clean return air filters every 100 hours
, more often 
in dusty conditions. 
To clean: 
1. Remove filter covers at both sides of cab rear 
wall by removing two nuts (A). 
2. Remove foam filter elements and clean with 
compressed air. 
3. Replace filter elements and covers. 
EVAPORATOR CORE
If air conditioning system produces insufficient 
cooling, a possible cause is clogged evaporator 
fins. Fins will clog up starting at the back side of 
the evaporator core (against cab wall). 
Evaporator core access and cleaning: 
1. Remove R/H console side panel (A). 
2. Remove nut securing seat support panel to 
mount on door side. 
3.  Release air suspension to fully lower operator's 
seat. Tilt seat (B) forward while tilting seat-back 
(C) rearward until seat is vertical. 
4. Lift the acoustical foam (E) at top of evaporator 
core and remove two nuts securing retainer (F). 
Remove retainer. 
5. Tilt evaporator core forward and vacuum off 
back side of core (at cab wall). Use a fin 
straightener to loosen clogs. 
6. Blow compressed air through core at an angle 
parallel to tubing alignment as shown. To 
prevent fin damage, blow air directly at fin 
edges, not at flat face. 
7.  If the compressed air can not be felt at the back 
of the core, proceed as follows: 
•  Remove foam filter (D) from drain tray and 
clean with warm water. 
•  With filter (D) still out, pour warm water down 
through the core and leave it to soak. (The  
drain tray will catch and remove run-off.) 
8. Blow compressed air through the core as in 
step 6. Repeat warm water soaking as required 
until air blows through evaporator core freely. 
9. Straighten any bent fins and reassemble. 
WARNING: To avoid cuts from 
evaporator fins, do not use bare 
hands to brush away clogs. 
A 
REMOVE FOR ACCESS TO
RETURN AIR FILTER 
EVAPORATOR CORE ACCESS & CLEANING 










