Cub Cadet 8404 Operator's Manual page 51

When Output Is Insufficient
Cause
Carbon build-up around orifice of
nozzle piece
Compression is insufficient
Overheating of moving parts
Valve out of adjustment
Air cleaner is dirty
Fuel injection pressure is wrong
Injection pump wear
When Color of Exhaust Is Especially Bad
See your Cub Cadet dealer.
Cause
Fuel governing device is bad
Fuel is of extremely poor quality
Nozzle is bad
Combustion is incomplete
- Clean orifice and needle valve, while being very careful not to damage
the nozzle orifice.
- Check nozzle. If defective, replace with new parts.
- Bad valve and excessive wear of rings, pistons, and liners cause
insufficient compression. Replace with new parts.
- Grind valves.
- Check engine lubrication system.
- Check to see if lube oil filter is working properly.
- Filter screens or elements deposited with impurities would cause poor
lubrication. Clean Screens.
- Check to see if bearing clearances ar within factory specifications.
- Check engine timing. Adjust timing to 18° before top dead center.
- Adjust to proper valve clearance:
Intake — 0.0098 in. (0.25mm)
Exhaust — 0.0118 in. (0.3mm)
- Clean the element and dust cup weekly, and replace element after
every 100 hours of operation.
- Adjust to proper pressure of 2.000 psi (140 kgf/cm
- Do not use poor quality fuel because it will cause wear of the the pump.
Only use No. 2 diesel fuel.
- Check the fuel injection pump element and delivery valve assembly and
replace as necessary.
- Contact your dealer for repairs.
- Select good quality fuel:
Above 14°F (-10°C) — No. 2 Diesel fuel
Below 14°F (-10°C) — No. 1 Diesel fuel
- If necessary, replace with new nozzle.
- Cause is poor atomization, improper injection timing, etc. because of
trouble in the injection system, or because of poor valve adjustment,
compression leakage, poor compression, etc. Check for the cause and
repair.
51
Countermeasures
2
Countermeasures
- 13.7 KPa).