Engine won't start
If the starter motor doesn't crank the engine, the fault is electrical: neutral, kill switch, main power, battery. If it cranks but the engine doesn't fire, look at fuel, air and glow plugs.
Manuals
Check step by step
Select your engine on its model page to see the relevant steps and part numbers.
- DIY
Does the starter motor crank the engine? If not: is the control in neutral, the kill switch reset and the main battery switch on?
Volvo Penta's starting table splits faults into a starter motor that doesn't turn and an engine that cranks but won't start.
Action: Put the lever in neutral and reset the emergency stop as described in the manual. If the diesel has a mechanical stop control, it should be pushed in.
- DIY
Measure the battery with a multimeter. A fully charged 12 V battery reads around 12.6 V at rest. Feel the cable lugs.
A flat battery or poor connections can stop the starter motor from turning, or make it turn slowly.
Action: Turn off the main power before you clean or tighten cable lugs. Charge the battery according to the charger's instructions. Never bypass the engine's relay or ground relay.
- DIY
Is there fuel in the tank and are the valves open?
The starter motor cranks as usual even when the fuel has run out.
Action: Fill up with the right fuel and open the valves. Check for leaks before you start again.
- DIY
Drain the pre-filter or water separator into a clear jar. Replace the filters if you find water or dirt.
Water, dirt and clogged filters are listed in the manufacturers' troubleshooting guides.
Action: Replace the filters as described in the owner's manual and catch any spillage. On a diesel, the low-pressure side must be bled after the system has been opened.
fuel filterpre-filter - Workshop
Diesel: is the stop control pushed in, the air filter clean and the preheating sufficient?
The D1/D2 table lists a pulled-out stop control, too short a preheat and a clogged air filter. Not all diesels have glow plugs.
Action: Start with the cold start procedure for your model and replace a clogged air filter. If you suspect the glow system, have the workshop test it. The TAMD40 and MD2010 have different systems.
glow plug - Workshop
Petrol engine that has fuel but still won't start: spark plugs and ignition system.
Sooty or damaged spark plugs, ignition faults and low voltage prevent starting.
Action: Follow the manual for your model. Never do a spark test in an engine compartment full of petrol vapour.
spark plug - Workshop
Starter motor still not turning? Check the fuses the manual points to. Relays and the starter motor are workshop jobs.
The fault can be in the fuse, relay, cable or starter motor.
Action: Only fit a fuse with the correct amp rating and never bypass a protective device. If the fuse blows again, or the engine is mechanically stiff, stop trying to start it.
When to call a workshop
Call a workshop if the engine doesn't start after these steps, if the fuse blows again or if fuel is leaking. If the engine stops with a metallic bang or turns unusually stiffly, make no further attempts to start it.
Frequently asked questions
My TAMD40 won't start despite changing the filter and bleeding the system. Should I replace the glow plugs or the pump?
Don't replace parts on a hunch. First check that fuel is getting through, that the stop function has been reset and what cold-start equipment your particular engine has. The D1/D2 table applies to the D1/D2, and the TAMD40 has a different glow system. Let the workshop take measurements before you buy expensive parts.
Can I bypass the ground relay and ground the starter motor directly?
No. The starting table is about measuring the battery, cables, fuses and relays. The grounding system should be left as it is. Have a workshop measure the starting circuit.
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