Why the Lifan engine does not start: a complete analysis of the reasons and solutions

Introduction: what to do if the Lifan engine refuses to start

If Lifan engine does not start - the starter is silent, turns over without grabbing, or the engine stalls immediately after starting - first check the obvious: the presence of gasoline in the tank, the position of the fuel valve and the serviceability of the spark plug. In models like Lifan 168F-2 (installed on walk-behind tractors, generators or mini-tractors) most often a clogged carburetor, a discharged battery, broken wiring or worn piston rings are to blame. Ignoring the first signs of a malfunction - for example, difficult cold starts or extraneous knocks - can lead to serious repairs, so diagnostics should begin immediately when malfunctions occur.

In this article we will look at all possible reasons why the Lifan engine does not start, - from the most obvious to hidden faults. You'll learn how to diagnose the problem yourself, what tools you'll need for repairs, and when to call a professional. We will pay special attention to models Lifan 168F, 170F and 177F, since they are most common in Russia and the CIS countries.

Important: if the engine previously worked stably, but now does not start after a long period of inactivity (for example, in winter), the reasons may differ from cases where the engine stalled during operation. We will consider both scenarios.

1. Checking the fuel system: from tank to carburetor

The first thing to rule out is problems with the fuel supply. Even if you are sure that there is gasoline in the tank, check its quality and the path to the carburetor. Chinese engines Lifan sensitive to dirty fuel and air pockets.

Start with an inspection fuel tank:

• 🔹 Gasoline level: Sometimes the sensor shows a balance, but it is not enough to start. Add fuel to the maximum mark.
• 🔹 Gasoline quality: if the engine has been standing for more than a month, the gasoline could stratify or lose octane number. Drain the old fuel and refill with fresh fuel (recommended AI-92 for most models).
• 🔹 Filter clogged: Sediment may accumulate in the tank, which clogs the mesh on the intake. Rinse the tank or replace the filter.

Next check fuel hose and carburetor:

• 🔹 Pinched hose: Inspect the hose for cracks or kinks. Sometimes it gets pinched by fastenings.
• 🔹 Air lock: Disconnect the hose from the carburetor and blow it out. If gasoline does not flow, there is a plug in the system.
• 🔹 Clogged jets: disassemble the carburetor and clean the jets with compressed air or a special cleaner (for example, HI-GEAR).

If after all the manipulations fuel enters the carburetor, but the engine still does not start, proceed to checking the ignition system.

2. Diagnostics of the ignition system: spark plug, coil, wires

Malfunctions in the ignition system are the second most common reason why it won’t start. Lifan. Start by checking spark plugs:

1. Unscrew the spark plug with a wrench (usually 16 mm or 21 mm depending on model).
2. Inspect its condition:
   • 🔥 Dry candle — fuel does not enter the cylinder (problem in the carburetor or fuel supply).
   • 💧 Wet candle — fuel overflow (the carburetor is faulty or the float is jammed).
   • ⚡ Black soot - rich mixture or oil in the combustion chamber.
   • 🔌 White soot - lean mixture or engine overheating.

Check the spark: insert the spark plug into the cap, apply it to the engine body and pull the starter. If there is no spark, the problem is in the coil or wires.

If there is no spark, check:

• 🔌 High voltage wire: Often chafed or oxidized. Ring with a tester (resistance should be within 5–10 kOhm).
• 🔄 Ignition coil: Measure the resistance of the primary and secondary windings. For Lifan 168F normal values: primary - 0.4–0.6 Ohm, secondary - 5–7 kOhm.
• 🔋 Gap between coil and flywheel: must be 0.1–0.15 mm. With a smaller gap the spark is weak, with a larger gap there is no spark.

If the coil is faulty, it will have to be replaced. For models Lifan 170F and 177F suitable coils from Honda GX200 - they are interchangeable.

3. Air problems: filter, dampers, leaks

Engine Lifan it will not start if there is no air entering the cylinder or there is too much air (suction). Start by checking air filter:

• 🌬️ Clogged filter: If the filter is clogged with dust, the engine suffocates. Wash it or replace it (original filters for Lifan are inexpensive - approx. 200–300 rub.).
• 🚪 Closed air damper: If the choke does not open at startup, the mixture is over-rich. Check the cable and damper mechanism.
• 🕳️ Air leak: Inspect the pipes from the carburetor to the engine. Cracks or loose connections lead to a lean mixture.

To check the tightness, you can use spraying method:

1. Start the engine (if it runs even a little).
2. Spray WD-40 or soap solution on the joints of the carburetor and intake manifold.
3. If the engine speed changes, there is an air leak.

How to check the carburetor for air leaks without starting the engine?

Disconnect the pipe from the carburetor and blow air into it (for example, with a compressor or pump). If air escapes through the joints, there is a leak. Seal the joints with caulk or replace the gaskets.

If, after eliminating the choke, the engine still does not start, proceed to checking the compression.

4. Compression and mechanical failures

Low compression is one of the most serious reasons why it won’t start. Lifan. It may fall due to:

• 🔧 Piston ring wear (especially after 500+ hours).
• 🔨 Coked rings (if the engine has been running for a long time on bad oil).
• 💥 Damage to valves (for example, after a water hammer).
• 🔩 Burnt cylinder head gasket (often accompanied by white smoke from the exhaust).

To measure compression you will need compression gauge. Verification algorithm:

1. Remove the spark plug.
2. Insert the tip of the compression gauge into the spark plug hole.
3. Pull the starter 5-7 times and record the maximum value.

Engine model	Normal compression	Minimum allowable
Lifan 168F-2	8–9 kg/cm²	6 kg/cm²
Lifan 170F	9–10 kg/cm²	7 kg/cm²
Lifan 177F	10–11 kg/cm²	7.5 kg/cm²

If the compression is below normal, try decarbonization:

1. Fill the cylinder through the spark plug hole 20–30 ml decarbonizers (for example, LAVR ML202).
2. Leave for 1-2 hours.
3. Crank the engine with the starter to remove any remaining product.
4. Change the oil and try to start the engine.

5. Starter and electronics: why the engine doesn’t turn over

If when you try to start the engine Lifan does not show signs of life (does not click, does not spin), the problem may be in the starter or electrical circuit. Let's look at the main reasons:

• 🔋 Low battery (for models with electric starter): check the voltage (12.6 V - normal, below 11.5 V - requires charging).
• 🔌 Oxidized contacts: Clean the battery terminals and starter wires with sandpaper.
• 🔄 Faulty starter: If you hear clicks when you turn the key, but the engine does not turn, check the retractor relay and starter brushes.
• 🔧 Winding break: if the starter does not respond at all, test the windings with a tester.

For recoil starter (rope), check:

• 🎣 Cable integrity: often breaks or gets chewed.
• 🔄 Return spring: If it breaks, the starter does not return to its original position.
• 🔧 Starter pawl: If it is broken, the starter cranks idle.

If the starter is working, but the engine does not turn, check fuses and ignition relay. Some models Lifan The fuse may blow due to a short circuit.

6. Sensors and electronics: hidden faults

Modern engines Lifan (for example, 177F or 190F) are equipped with sensors that can block the launch. If all previous checks have failed, pay attention to:

• 📡 Oil level sensor: If the oil is below the minimum, some models will block starting (for example, Lifan 188F).
• 🌡️ Temperature sensor: If it is faulty, the ECU may not adjust the mixture correctly.
• 🔄 Hall sensor: responsible for the moment of sparking. If it is broken, the spark will be weak or absent.
• 🔋 ECU (electronic control unit): rare, but fails after power surges.

To test the sensors you will need multimeter. For example, for a Hall sensor:

1. Remove the distributor cover.
2. Connect the multimeter probes to the sensor contacts.
3. Rotate the crankshaft (by hand or with a starter). The voltage should vary from 0.4 V up to 12 V.

How to trick the oil level sensor to start the engine?

If the sensor is faulty, but the oil is normal, you can temporarily close its contacts (for example, with a piece of wire). However, this solution is only for diagnostics - after starting, the sensor must be replaced!

If you suspect a faulty ECU, try resetting the errors by disconnecting the battery at 10–15 minutes. If this does not help, the unit will have to be reflashed or replaced.

7. External factors: weather, fuel, oil

Sometimes the engine Lifan does not start due to external conditions, not breakdowns. Let's consider typical cases:

• ❄️ Cold weather:
  • Use winter oil (5W-30 or 0W-40).
  • Warm up the engine with a hair dryer (do not direct hot air at plastic parts!).
  • Add a cold start additive to your gasoline (e.g. LIQUI MOLY Start Fix).
• ☀️ heat:
  • Check to see if the engine is overheating (touch the cylinder head - if it burns, let it cool).
  • Make sure the radiator is not clogged with dust.
• ⛽ Bad fuel:
  • If you refuel at a questionable gas station, drain the gasoline and wash the carburetor.
  • Add fuel system cleaner to the tank (Wynn's or Lavr).

Pay special attention oil:

• 🛢️ Incorrect viscosity: if the oil is too thick (for example, 15W-40 in winter), the starter will not be able to crank the engine.
• 🔥 Oil overflow: If the level is above the maximum, oil can enter the combustion chamber and “flood” the spark plug.
• 💀 Old oil: if the oil has not been changed again 100 hours, it loses its properties and can cause jamming.

8. When to contact specialists: signs of serious damage

Not all problems can be fixed on your own. Contact the service if:

• 🔧 Engine jammed: if the starter cannot turn the crankshaft, and it also does not rotate manually, this is a sign of scoring or destruction of the bearings.
• 💥 Knocks are heard in the engine: A metallic knock indicates destruction of the connecting rod bearings or piston.
• 🌊 White smoke comes out of the exhaust: This could be a sign of a blown head gasket or a crack in the block.
• ⚡ There is a spark, fuel flows, but the engine does not start: the valve timing may be disrupted (the timing belt has broken or the chain has jumped off).

The cost of repairs in the service depends on the breakdown:

Type of repair	Cost (RUB)	Deadlines
Replacing piston rings	3 000–5 000	1–2 days
Cylinder head repair (replacement of valves, lapping)	4 000–7 000	2–3 days
Replacing crankshaft bearings	6 000–10 000	3–5 days
Major repairs (liner, crankshaft grinding)	12 000–20 000	5–7 days

If your Lifan is under warranty, do not disassemble it yourself - this may deprive you of the right to free repairs. Contact an official service center (their list can be found on the website Lifan Russia).

FAQ: Frequently asked questions about starting Lifan engines

❓ Why does the Lifan engine start and immediately stall?

This is a typical sign carburetor malfunction (clogged jets, leaky float) or air leak through the gasket. Also check Hall sensor - if it gives the wrong signal, the engine may stall immediately after starting.

❓ Is it possible to start a Lifan engine without an air filter?

Short-term - yes, but only for diagnostic purposes. Prolonged operation without a filter will lead to dust entering the cylinder and accelerated wear of the piston group. If the filter is clogged, it is better to wash it or replace it.

❓ Why does the starter turn, but the engine does not catch?

There are several reasons:

1. No spark (check spark plug, coil, Hall sensor).
2. No fuel flows (carburetor or fuel hose is clogged).
3. No compression (worn rings or valves).
4. The valve timing is off (the timing belt has slipped off).

Start by checking the spark and fuel supply.

❓ What oil should I pour into the Lifan 168F engine?

The manufacturer recommends semi-synthetic oil SAE 10W-30 or 10W-40 (for example, Lukoil Lux or Shell Helix HX7). Suitable for winter use 5W-30. Oil volume - 0.6 l.

❓ What kind of gasoline should I fill in Lifan 170F?

The best option is AI-92. AI-95 also suitable, but does not provide noticeable advantages, and is more expensive. It is strictly forbidden to use AI-80 or diluted gasoline - this will lead to detonation and accelerated engine wear.

If your question is not covered in the article, study operating instructions to your model Lifan or use forums (eg Honda-Club, where there is a section on Chinese engines).