Bukh DV36/48, Workshop Manual

Page: 191 / 196

009W2329.R01
T3
1. Engine does not start
SYMPTOM CAUSE REMEDY
Insufficient or very little compression Inlet and/or exhaust valves leaking Grind or replace the valves, mill the seats
Inlet and/or exhaust valves sticking
Grease valve stems with 2/3 gas oil and 1/3 lub.
Oil. If necessary clean the valves.
Insufficient rocker arm clearance
Adjust to 0.25 mm inlet and 0.3 mm exhaust when
engine is cold (turn left)
Piston rings stuck in grooves or are worn Replace piston rings
Valve springs broken or are weak Replace springs
Insufficient or no pressure from fuel pump Air in fuel system or nozzles sticking Bleed or renew nozzles
Thermo start out of order No fuel (valve leaking) Fill up (renew thermo-start)
Electric supply out of order
Check and/or replace switch and connections.
Chech fuse
Engine does not reach normal revs Unloaded battery or defective Battery to be charged or renewed
Starter motor turns engine too slowly Loose or corroded connections Tighten or clean connections
2. The engine starts, but stops soon after
The engine starts, but stops soon after Empty fuel tank Refill and bleed
Air in fuel system Bleed
Nozzle sticking Replace nozzle
Fuel filter clogged Replace filter element. Clean the tank
3. The engine does not reach maximum output
Difficult to start None or insufficient compression See ”engine does not start”
The engine revs. Is reduced considerably
when loaded
Fuel supply choked up.
Air/water in fuel system Check fuel system thoroughly
Governor incorrectly adjusted or something
in the system works sluggishly
Adjust the governor. Check governor system and
correct the error
Hot engine (smell of heat) Insufficient cooling water supply Stop engine. Check cooling water pump
Damaged cylinder liner or bearings Check bearings, piston and cylinder, if necessary
replace them
4. Knocking operation of engine
The engine runs unevenly Air/water in fuel system
Fuel filter clogged
Bleed see ”engine does not start”
Replace filter element. Clean the tank
5. Engine speed too high
Governor not working properly Governor spindle is bent or works sluggish Repair or replace spindle
Governor not properly adjusted Governor arm has turned on the spindle Adjust arm
Engine runs too fast during idling Idler spring too tight Repair or replace spring
6. Engine knocks
Hard knocking sound at the combustion Incorrect adjustment of the injection time Adjust timing
Knocking sound from engine Loose connecting rod bolts
Worn or burnt bearings
Piston and cylinder liner highly worn
Tighten bolts
Replace bearing shells
Replace piston/cylinder liner
7. The engine smokes
Black smoke Clogged air inlet filter Clean filter
Insufficient compression See ”engine does not start”
Blue smoke The lube oil passes piston and oil rings an
penetrates into combustion chamber, or
vacuum valve defective
Replace oil rings and possibly the piston rings.
Clean vacuum valve
Grey smoke Thermostart valve is leaking Replace
8. Excessive consumption of lubricating oil
Blue smoke Oil- and piston rings are worn Replace oil- and piston rings, if required
Piston and cylinder liner highly worn Replace
Defective vacuum valve Replace
Lub. oil leaks out of crankshaft bearings Worn oil seal ring Replace
9. Excessive fuel oil consumption
Lubricating oil thinned with fuel oil Leakages at the fuel lift pump Check lift pump and replace if necessary
Fuel pipes or hoses leaking Check fuel line
10. The engine gets too warm or too cold
Cooling water temperature too high
(smell of heat)
Unsufficient cooling water supply caused
by:defective water pump, choked strainer or
a defective thermostat
Investigate pump rotor for broken wings or lost
driver screw. Clean strainer. Clean or replace
thermostat
Cooling water temperature too low Defective thermostat Clean or replace thermostat
11. Insufficient or no lubrication oil pressure
Oil warning lamp lights up. Oil pressure
gauge indicates abnormally low oil pressure
Insufficient lube oil in the engine Check and refill
Leakage in lube oil system Tighten and refill
Relief valve sticking or spring too weak Clean bore and valve, stretch or replace the spring
As to defects of the fuel pump see special section on this page H13.