Bailey V5, User Manual

Page: 15 / 18

Bailey V5 Engine Manual V1.0
Page 13
Maintenance Procedures – Drive Belt Tensioning
Maintenance Procedures - Valve Clearance Adjustment
The ideal drive belt tension is the minimum required to
prevent any slippage. Some slipping (slight chirping noise)
at idle is quite normal. We recommend an optimum belt
deflection of 5-8mm (as shown in picture below)
There is a simple test to tell if the drive belt is slipping;
From cold allow the engine to briefly warm up and then
hold at full power for 10 seconds and stop the engine. If
the drive belt is cold to touch, then the tension is correct, if
it feels hot then it may be slipping and will require
adjusting. The belt will be pre-tensioned at the factory and
is checked at the free 10hr service we offer.
We have often found that even after 200 hours, no drive
belt adjustment has been necessary.
Firstly ensure the master switch is off.
Disconnect engine breather hose and remove cam
cover. Rotate propeller until inlet valve (nearest the top
of the engine) is fully closed and the cam lobe is 180º
from the cam follower. Using a suitable feeler gauge,
inserted between the valve top and the cam follower
adjusting screw, check and/or adjust by loosening the
9mm lock nut (see specifications on page 2 for valve
clearances)
The same procedure is used on the exhaust valve
(nearest the exhaust), however, be aware of the easy
start actuator positioned on the exhaust cam base
circle. Make sure the cam follower is clear of this in
order to get a correct measurement.
After adjustment ensure both lock nuts are tightened and re-fit cam cover and engine breather hose. Wipe off
any excess oil from the lower cylinder head fins.
The drive belt can be adjusted by slackening the two M6 bolts on the top of the reduction pylon, wedging
the pylon apart slightly at the split using a small screwdriver and turning the eccentric drive belt adjuster,
with an 8mm Hex key inserted into the centre of the large reduction pulley, a slight clockwise rotation will
tighten the belt, anti-clockwise rotation will loosen the belt. After adjustment re-tighten the two M6 bolts
and test the belt deflection.
N.B. Do not over-tighten belt – This may lead to premature bearing failure and reduction in available thrust.