Service Manual

8-6
WPM Drive Systems Manual
BBC/BOS/BCS
ControlBoxDisassembly
Note: WhenservicingtheBBCcontrolbox,be
carefulnottodisassembletheunitanyfurther
thannecessaryasitwillthenbecomedifcult
totroubleshoot.Instead,removetheright
housinghalf,thenoperatethecontrolbox
whilewatchingforproperfunctionofinternal
components.SeeStep5belowformore
information.
1. Place a piece of duct tape over the heads of the
carriage bolts passing through the handle and the
BBC control box. This will prevent them from falling
out later during troubleshooting.
2. Bend the locking tab securing the throttle control to
the control panel, then tap the throttle control out
using a rubber mallet.
3. Remove the 3 anged head screws retaining the 2
control box halves.
4. Carefully remove the 2 ange nuts retaining the
control box to the handle and remove the right
control box half. Be careful not to dislodge any
internal components.
5. Reinstall the ange nuts to help hold things together.
Determine if any of the components inside the
control box are malfunctioning.
CAUTION! Wearglovesandeyeprotectionwhen
operatinganopencontrolboxasthebuckling
springcouldyout.
Note: Thecableendsandendofthespringarenot
retainedoncetherightcoverisremoved.Be
suretouseoneofthetwomethodsbelowto
retainthem.
The rst and quickest method is to manually hold the
ends of the cable and the end of the buckling spring
while operating the control bar. However, with the
right case half removed, the leaf spring is no longer
in place and you will not be able to observe release
of the BBC cable lever.
When the control bar is released, the tip of the control
hook catches on the leaf spring causing it to rotate. This
releases the BBC cable lever, thereby causing the BBC
to declutch and apply the blade brake (Fig. 186).
Fig186 3428-0290
A. Contact point C. Flange nut
B. Leaf spring
A
B
C