centerline
Member
we Have a Daewoo G30E dual fuel, conventional forklift that starts and runs great, UNTIL it gets ran hard/travels at higher speed for a couple minutes, then it begins to slowly start misfiring.
if we stop and let it return to an idle, it misfires and sometimes dies, and sometimes stays running... when it dies, when we attempt to restart it, it seems as if there is no compression except on one cylinder.... but within a couple minutes it will restart with a miss, and then pick up all 4 cylinders again and run fine, until it gets ran hard again.
when the engine remains running but badly misfiring, it will begin firing on all 4 cylinders within about 30 seconds and run fine again.... until it gets ran hard again.
I have thought it may be a tight valve train that is heating up and holding the valves open too far, but this seems like kind of a stretch of the imagination, considering it has hydraulic lifters and it runs so good when the rpms are at the lower end of the tach...
the the machine does not have to be moving for the engine to act up, as it will do the same thing while setting in neutral and pegging the throttle against the governor..... it does NOT over rev, but will run fine for a little bit and then start misfiring, and yet still run great after having a chance to cool down for a few seconds...
the mis-fire/fault is dependable and reproducable everytime....
we have replaced the oil and filter, fuel filter, engine computer, O2 sensor, crank position sensor and the distributor pick up coil, spark plugs and plug wires but without any change in performance...... where should I look next?.... thanks
if we stop and let it return to an idle, it misfires and sometimes dies, and sometimes stays running... when it dies, when we attempt to restart it, it seems as if there is no compression except on one cylinder.... but within a couple minutes it will restart with a miss, and then pick up all 4 cylinders again and run fine, until it gets ran hard again.
when the engine remains running but badly misfiring, it will begin firing on all 4 cylinders within about 30 seconds and run fine again.... until it gets ran hard again.
I have thought it may be a tight valve train that is heating up and holding the valves open too far, but this seems like kind of a stretch of the imagination, considering it has hydraulic lifters and it runs so good when the rpms are at the lower end of the tach...
the the machine does not have to be moving for the engine to act up, as it will do the same thing while setting in neutral and pegging the throttle against the governor..... it does NOT over rev, but will run fine for a little bit and then start misfiring, and yet still run great after having a chance to cool down for a few seconds...
the mis-fire/fault is dependable and reproducable everytime....
we have replaced the oil and filter, fuel filter, engine computer, O2 sensor, crank position sensor and the distributor pick up coil, spark plugs and plug wires but without any change in performance...... where should I look next?.... thanks
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