Removal cylinder heads (cylinder head) on Nissan Almera - a task that owners face when overhauling an engine, replacing a gasket or eliminating an oil leak. The procedure requires caution: errors during dismantling can lead to surface deformation, thread damage, or debris entering the cylinders. In this article we will analyze the process step by step, indicate critical points for GA16DE, QG15DE and HR16DE engines, and also give advice on diagnosing faults before starting work.

Important: the instructions are universal for models Almera N16 (2000–2006), Almera Classic (B10, 2006–2012) And Almera G15 (2012–2019), but there are nuances for each motor. For example, on HR16DE (1.6 l, 110 hp) you will have to remove the additional intake manifold bracket, and on QG15DE — take into account the features of the VVT system. If you are not confident in your abilities, it is better to entrust the work to professionals: the cost of correcting errors often exceeds the price of the service itself.

When is cylinder head removal required on a Nissan Almera?

The cylinder head is dismantled not only during major repairs. Here are typical cases when the procedure is inevitable:

  • 🔧 Burnt out cylinder head gasket — signs: white smoke from the exhaust, emulsion in oil, engine overheating. On Almera N16 with motor GA16DE this is a common problem after 150 thousand km.
  • 💧 Oil or antifreeze leak from under the head. For example, on QG15DE Oil channels often leak in the area of the 4th cylinder.
  • 🔨 Cracks in the cylinder head — diagnosed after water hammer or severe overheating. On Almera G15 with HR16DE Cracks often appear between valve seats.
  • ⚙️ Replacing guide bushings or valves. For example, with increased oil consumption due to wear of the valve stem seals.
  • 🔥 Repair after a broken timing belt - on Almera Classic with QG15DE this almost always results in bent valves.

Before removing, be sure to carry out diagnostics. For example, if you suspect a blown gasket, check the compression in the cylinders and the presence of gases in the cooling system using leak tester. On Almera G15 with HR16DE The symptoms of a burnt gasket are often confused with a thermostat malfunction - in both cases the engine overheats, but the reasons are different.

⚠️ Attention: If the dashboard lights up Check Engine with an error P0300 (multiple misfires), do not rush to remove the cylinder head. First check the spark plugs, coils and high-voltage wires - for Almera N16 this is a common cause of false diagnoses.

Preparation for removal: tools and materials

To work you will need a specialized tool. Don’t skimp on quality - for example, cheap torque wrenches They often lie by ±10%, which is critical when tightening the cylinder head bolts. Here's the full list:

Tool/material Purpose Notes
Torque wrench Tightening the cylinder head bolts Range 20–100 Nm, error no more than 3%
Set of sockets and extensions Dismantling fasteners A 10, 12, 14 mm head is required
Screwdriver with magnetic tip Removing small parts Prevents bolts from falling into the pallet
Valve spring puller When replacing valve stem seals For HR16DE you need a puller with an adapter for small plates
Sealant Loctite 574 or Permatex Ultra Black Surface sealing Do not use silicone sealants!

Additionally prepare:

  • 🧴 Carburetor Cleaner — to remove carbon deposits from the surface of the cylinder head.
  • 🧲 Magnetic tray - so as not to lose small parts (for example, valve cotters).
  • 📐 Flat probe 0.05–0.1 mm - to check the flatness of the head.
  • 🔧 Special key for timing belt tensioner - on Almera G15 this is KV10118300.
📊 What engine is installed in your Almera?
  • GA16DE (1.6 l, N16)
  • QG15DE (1.5 l, Classic)
  • HR16DE (1.6 l, G15)
  • Other

Step-by-step instructions: removing the cylinder head on a Nissan Almera

Let's look at the process using an example Nissan Almera N16 with engine GA16DE. For other models we will indicate the differences. Opening hours: 6–8 hours for an experienced master, 10–12 hours for a beginner.

Drain the antifreeze and oil|Disconnect the battery terminal|Remove the air filter and pipes|Install the piston of the 1st cylinder to TDC-->

Step 1: Removing the Attachment

Start by disconnecting all pipes and connectors:

  1. Remove intake manifold (6 bolts x 12 mm). On HR16DE additionally disconnect the absolute pressure sensor (MAP-sensor).
  2. Disconnect the sensor connectors:
    • 🔌 Coolant temperature sensor (ECT).
    • 🔌Camshaft position sensor (CMP).
    • 🔌 Injectors (marked with harnesses with clips).
  • Remove accelerator cable (on Almera Classic with QG15DE it is attached to the throttle body).
  • Disconnect the system hoses crankcase ventilation And adsorber.

    • Step 2: Removing the Timing Belt and Camshafts

    This is the most critical stage. Errors here will lead to disruption of the valve timing.

    Algorithm for GA16DE:

    1. Secure the crankshaft pulley using special stopper (or screwdrivers through a hole in the block).
    2. Loosen the timing belt tensioner with a 14 mm wrench and remove the belt.
    3. Unscrew the fastening bolts camshaft gears (use an extension to avoid stripping the threads).
    4. Remove the camshafts, having previously marked their position with a marker (on QG15DE the shafts are asymmetrical!).
    What happens if you mix up the camshafts?

    On QG15DE The intake and exhaust shafts have different cam profiles. If they are mixed up, the engine will run rough and the valves may collide with the pistons at high speeds.

    On Almera G15 with HR16DE additionally you need:

    • Remove phase regulator (3 bolts per 10 mm).
    • Disconnect the sensor connector VVT (located on the front cylinder head cover).

    Step 3: Unscrewing the cylinder head bolts

    Cylinder head bolts on Nissan Almera disposable — they must be changed after removal! If used repeatedly, they may burst when tightened.

    Unscrewing order (for all engines):

    1. Loosen the bolts in reverse tightening sequence (see diagram below).
    2. Use a torque wrench to control the force.
    3. If the bolt does not budge, do not apply excessive force - wet it WD-40 and wait 10 minutes.

    Cylinder head bolt tightening diagram (for GA16DE/QG15DE):

    10  6  2  4  8
    

    1  5  3  7  9

    Tightening torque:

    • 1st stage: 20 Nm
    • 2nd stage: 40–50 Nm (in 2 approaches)
    • 3rd stage: turn 90° (only for HR16DE)

    💡

    Before unscrewing the bolts, clean their heads with a wire brush. Dirt under the key can lead to breakage of the edges, especially on the bolts near the exhaust manifold, where carbon deposits accumulate more actively.

    Step 4: Removing the cylinder head

    After unscrewing all the bolts, carefully pry the cylinder head plastic installation tool (not metal, so as not to damage the surface!). If the head does not budge, check that all the bolts are unscrewed - they often forget about the 2 bolts under the intake manifold on QG15DE.

    Place the removed cylinder head on clean wooden surface (not on concrete!). Cover the engine cylinders with a clean rag to keep debris out.

    ⚠️ Attention: On Almera G15 with HR16DE installed in the head hydraulic compensators. Do not turn it upside down - the expansion joints may fall out of their sockets.

    Common mistakes and how to avoid them

    Even experienced craftsmen sometimes make mistakes when working with cylinder head. Here are the most common:

    • 🔩 Reuse of cylinder head bolts - on Almera N16 this leads to breakage of the bolt in the block. New bolts cost ~500 rubles, and drilling out a fragment costs from 3000 rubles.
    • 🧹 Dirt getting into the cylinders — even fine dust can scratch the cylinder mirror. Always cover the openings with a clean cloth.
    • 🔧 Incorrect bolt tightening - on HR16DE The tightening torque of the 3rd stage (turn by 90°) is often missed, which leads to gasket leakage.
    • 💦 Using silicone sealant — it cannot withstand temperatures and pressure in the cylinder head. Only anaerobic type sealants Loctite 574.
    • ⚡ Failure to check head flatness - even a slight deformation (0.05 mm) will cause the gasket to burn out. Check with a ruler and feeler gauge.

    On Almera Classic with QG15DE people often forget about intake manifold bracket mounting boltsthat pass through the cylinder head. If you don't unscrew them, the head won't come off and the bolts can break.

    💡

    After removing the cylinder head, be sure to check the condition of the gasket. If it burns out between the 3rd and 4th cylinders (a common problem on GA16DE), look for the cause in overheating or detonation.

    Checking and repairing the cylinder head after removal

    The removed head must be inspected for cracks, wear and deformation. Here's what to check:

    • 🔍 Flatness of the mating surface - use a ruler and feeler gauge. Allowable gap: no more than 0.05 mm over the entire length.
    • 💎 Valve seat condition - on HR16DE The exhaust valve seat of the 1st cylinder often wears out.
    • 🛢️ Oil channels - must be clean, without soot. On Almera N16 The channels often become clogged due to low-quality oil.
    • 🔗 Valve guides — play more than 0.1 mm requires replacement.

    If the head is deformed, it can be ground, but not more than 0.2 mm. On QG15DE After grinding, it may be necessary to replace the valves - they become too “recessed”.

    To clean the cylinder head from carbon deposits, use:

    • 🧽 Ultrasonic bath - the best option for removing carbon deposits from oil channels.
    • 🧴 Special cleaners (For example, LIQUI MOLY Motor Clean).
    • 🔨 Soft brush — for mechanical cleaning (do not use metal brushes!).

    Installation of cylinder head and first start

    Assembly is carried out in reverse order, but there are critical points:

    1. Clean the mating surfaces block and head. Use acetone or white spirit.
    2. Install a new gasket. On HR16DE The gasket is asymmetrical - follow the inscription TOP.
    3. Tighten the bolts in 3 stages (see diagram above). On Almera G15 after tightening, check the valve clearance - it should be 0.25–0.30 mm.
    4. Install the timing belt, combining the labels:
      • 🔄 On the crankshaft pulley - the risk should be looked at 0°.
      • 🔄 On camshafts - the marks should be at the top (for GA16DE).

    After assembly do not start the engine immediately. First:

    1. Rotate the crankshaft by hand 2 turns to check for seizure.
    2. Check compression (should be 12-14 bar for QG15DE).
    3. Fill with antifreeze and check the system for leaks (for Almera N16 the pump often leaks after assembly).
    ⚠️ Attention: At the first start after repairing the cylinder head on HR16DE may burn Check Engine with an error P0011 (VVT phases). This is normal - the error will clear after 2-3 warm-up cycles.

    FAQ: Frequently asked questions about removing the cylinder head on a Nissan Almera

    Is it possible to remove the cylinder head on an Almera G15 without removing the pan?

    Technically yes, but it is extremely inconvenient. On HR16DE The lower cylinder head bolts are located close to the pan, and without removing it you risk dropping tools or debris into the oil. It is better to remove the pan (8 bolts of 10 mm) and at the same time change the oil.

    Which cylinder head gasket should I choose for Almera N16?

    Original gasket - Nissan 11044-4M200 (for GA16DE). Alternatives:

    • Ajusa 10144200 (Spain, good quality).
    • Elring 443.240 (Germany, more expensive, but more reliable).

    Avoid cheap Chinese analogues - they often burn out after 20-30 thousand km.

    Is it necessary to grind the cylinder head after overheating?

    Definitely! Even if there is no visual deformation, check the flatness. On QG15DE after overheating, the surface near the 3rd cylinder often “leads”. Sanding costs ~1500 rubles, but will save you money on repeated repairs.

    What sealant should I use for the cylinder head?

    Only anaerobic sealantsresistant to high temperatures:

    • Loctite 574 (best option).
    • Permatex Ultra Black (an alternative, but holds pressure worse).

    Apply a thin layer only to the junction of the block and the head, avoiding getting into the oil channels.

    What to do if the cylinder head bolt breaks in the block?

    Do not try to drill it yourself - the risk of damaging the block is too great. Contact the service where there is special extractor and experience with Nissan. Average cost of retrieving a fragment: 3000–5000 rubles.