Specifications

Service Training
Section 4.9
Page 54
12.05
ADJUSTING THE CO CONTENT
Prerequisites for adjustment:
- Firing point checked and if necessary corrected: desired value 18 ± 2 ° before TDC
(from 01/2005: 8 ± 2 ° before TDC).
- With truck warmed up, hydraulic oil at 60 – 70 °C, operating hydraulics pressure relief valve set to 265
bar.
- Parking brake locked in braked position.
Adjustment:
- Turn idling mixture adjustment screw (3) to its limit stop and then unscrew by three turns.
- Connect CO meter.
- Start engine and when truck is warmed up at a low idling speed (750 – 800 rpm) determine CO value.
Target value: CO ≤ 0.1 % by volume
If CO > 0.1 % by volume, unscrew screw (3) more, engine must be running in idling mode
but clearly regularly.
- Place full-load mixture adjustment screw (2) in the middle between L and R (the screw is located at the
gas intake in the mixer).
- Connect CO meter.
- With the footbrake on, bring the engine to maximum running speed, activate tilt control lever fully to the
limit stop and hold there, at the same time turn the steering to the limit stop too, and hold, thereby applying
a load to the engine.
- Determine CO value of the engine under this load.
Target value: CO ≤ 0.1 % by volume
Correction: To reduce CO value = turn adjustment screw in direction L.
To increase CO value = turn adjustment screw in direction R.
(to enhance engine performance)
NOTE: The engine cannot be set to this setting with a running speed lower than 1750 rpm.
In models with catalysers, the speed cannot go below 1850 rpm.
- Screw in limit stop screw (9) against limit stop (8) to the point that when pressing the magnet axis up to
the limit stop, the running speed is kept at about 500 rpm.