Nissan Almera is one of the most popular budget sedans on the Russian market, but even this reliable car requires engine repair over time. Tightening the cylinder head (cylinder head) bolts is a critically important procedure on which the tightness of the combustion chamber, the life of the gasket and the engine itself depend. The error is all 0.5 Nm can lead to gasket burnout, antifreeze getting into the oil, or even deformation of the head surface.

In this article you will find current data on cylinder head tightening torque for all generations Almera (including N16, G15 And B10), a detailed diagram of the tightening order, recommendations for tools and typical mistakes that even experienced craftsmen make. We will also look at why old bolts should not be used, how to check their condition and what to do if the torque has been exceeded.

Why is the correct cylinder head tightening torque important?

Cylinder head bolts operate under extreme conditions: high temperatures (up to 120°C), vibrations and constant heating/cooling cycles. If they are tightened less than normal, the cylinder head gasket will not provide a tight seal, which will lead to:

  • 🔥 Gasket burnout between the cylinders or in the area of the cooling ducts.
  • 💧 Antifreeze getting into the oil (emulsion in the pan) or oils in antifreeze.
  • ⚡ Loss of compression and unstable engine operation.
  • 🚗 Engine overheating due to impaired coolant circulation.

On the other hand, over tightening no less dangerous: it can:

  • 🔧 Break the thread in the cylinder block (especially important for aluminum blocks GA16DE And QR25DE).
  • 📉 Deform the cylinder head surface, which will require grinding or replacement.
  • 💥 Cause bolt breakage (a common problem when using old or poor quality bolts).
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If after assembly the engine begins to “trouble” or bubbles appear in the expansion tank, first check the tightening torque of the cylinder head. Often the problem lies in uneven reinforcement of the bolts.

Cylinder head tightening torque table for Nissan Almera all generations

Tightening torques depend on engine modifications, cylinder block material and bolt type (standard or TTY — Torque-To-Yield, "stretching"). Below is a current table for the most common motors Almera:

Engine model Years of manufacture Bolt type Tightening torque (Nm) Tightening order Notes
GA14DE (1.4 l) 1995–2000 (N15) Standard 69–75 (in 2 stages: 50 → 70–75) From the center to the edges Bolts used M10×1.25
GA16DE (1.6 l) 1998–2006 (N16) Standard 95–105 (in 3 stages: 50 → 80 → 95–105) Crisscross Bolts M11×1.25, elongation check is mandatory!
QR25DE (2.5 l) 2006–2012 (G15) TTY 45 + 90° + 90° Spiral from the center Bolts disposable! Replacement is required.
HR16DE (1.6 l) 2012–present (G15, B10) TTY 25 + 60° + 60° From the center to the edges A torque wrench with an inclinometer is required.

Important: For engines QR25DE And HR16DE with bolts TTY The tightening torque is indicated in the format "preliminary torque + rotation angle". For example, 25 Nm + 60° + 60° means that after reaching 25 Nm, the bolt is turned 60°, then another 60°.

📊 What engine is installed in your Almera?
  • GA16DE (1.6 l, N16)
  • QR25DE (2.5 l, G15)
  • HR16DE (1.6L, B10)
  • Other (specify in comments)

The procedure for tightening cylinder head bolts: diagram and rules

No less important tightening sequence bolts It ensures uniform distribution of the load on the gasket and the block head. For most engines Nissan Almera used spiral pattern (spiral from center) or criss-cross.

Below is a universal diagram for 4-cylinder engines (for example, GA16DE):



10   6   2   4   8


7   3   1   5   9

Tightening order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 9 → 10.

For QR25DE (2.5 l) different scheme (10 bolts):



10   4   1   5   9


6   2   3   7   8

Order: 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 9 → 10.

Clean the threaded holes in the block from oil and dirt|Check the bolts for deformation (length no more than 95 mm for GA16DE)|Apply a thin layer of engine oil to the threads (except TTY bolts)|Install a new cylinder head gasket (Nissan or Febi original)|Use a torque wrench with an accuracy of no more than ±3%-->

Tools for tightening the cylinder head: what is needed and what should not be replaced

To properly tighten the cylinder head bolts you will need:

  • 🔧 Torque wrench with range 20–150 Nm (for TTY-bolts require a wrench with a protractor).
  • 🔨 Socket head on 10 mm or 11 mm (depending on the engine).
  • 📏 Vernier caliper to check the length of the bolts (critical elongation is a sign of wear).
  • 🧴 Thread cleaner (For example, WD-40 Specialist) and a lint-free cloth.

What not to do:

  • ❌ Use impact wrench - he is not in control of the moment.
  • ❌ Tighten the bolts by "eye" or by feeling.
  • ❌ Apply universal keys with ratchet without dynamometer.
  • ❌ Lubricate the bolts TTY oil - this distorts the tightening torque.
Why can't I use old cylinder head bolts?

Cylinder head bolts are subject to plastic deformation when tightening, this is especially true TTY-bolts When used repeatedly, they do not provide the necessary force, which leads to:

- uneven positioning of the gasket (risk of burnout);

- spontaneous loosening of bolts over time;

- increased risk of breakage when tightening.

Exception - standard bolts GA16DE, but it is recommended to replace them every time the cylinder head is dismantled.

Typical mistakes when tightening the cylinder head and how to avoid them

Even experienced craftsmen sometimes make mistakes that lead to serious consequences. Here are the most common:

⚠️ Attention: If after assembly the engine does not start or runs intermittently, do not try to tighten the bolts immediately. First check the compression and the presence of antifreeze in the oil. A hot lift can deform the head!

Error 1: Failure to follow the tightening order

By tightening the bolts randomly, you create uneven pressure on the gasket. This leads to its squeezing out or burnout in weak areas. Always follow the diagram for your engine (see section above).

Error 2: Using the wrong key

Torque wrenches have an error. Cheap models (especially pointer models) can give an error of up to ±10%what for HR16DE (where the moment is critical) is unacceptable. Use a calibrated electronic key or a certified mechanical key.

Error 3: Tightening on a cold engine

For most engines Nissan the tightening torque is indicated for cold block (temperature 20–25°C). If you tighten it while the engine is hot, the bolts will loosen after they cool as the metal shrinks.

Mistake 4: Reusing Bolts TTY

Bolts type Torque-To-Yield (used in QR25DE And HR16DE) are designed for single stretch. Their reuse leads to:

  • 🔩 Insufficient effort of diligence of the head.
  • 💥 Risk of breakage when tightening.
  • 📉 Gradual loosening of bolts during operation.
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If you have removed the cylinder head on an engine with bolts TTY, their necessarily need to be replaced with new ones. Cost of a set of bolts for HR16DE - about 1500–2000 rubles, which is cheaper than repairs after a gasket burns out.

How to check the tightening torque after assembly?

After tightening the bolts, it is recommended to check their torque using 30–60 minutes (this is called "control tightening"). To do this:

  1. Set the torque wrench to 10% below normal (for example, for GA16DE — 65 Nm).
  2. Try to tighten each bolt. If the key “clicks,” the bolt is loose and needs to be turned back to normal.
  3. If the bolt does not give in, the torque is normal.

For bolts TTY No control check is carried out! They should not be re-tightened after the initial tightening.

Also after the first start of the engine (after 100–200 km) recommended:

  • 🔧 Check oil and antifreeze levels (for leaks).
  • 📊 Measure the compression in the cylinders (should be at least 12 bar in each).
  • 🔍 Inspect the cylinder head gasket for leaks (especially in the area of the 3rd cylinder, where burnout most often occurs).

What to do if the tightening torque has been exceeded?

If you accidentally exceed the tightening torque, proceed according to the following algorithm:

⚠️ Attention: If the bolt TTY was pulled by more than 15° from the norm, it cannot be reused - it must be replaced, even if it looks intact on the outside.

Step 1: Assess the damage

  • If the excess is up to 10% (for example, instead of 95 Nm it worked 100 Nm), the risk is minimal. It is enough to check the compression after assembly.
  • If the excess more than 20% — there is a high probability of head deformation or thread breakage. Requires dismantling and diagnostics.

Step 2: Check the Threads

Remove the bolt and inspect the threads in the cylinder block. If the coils are damaged:

  • 🔧 Use threaded insert (helicoil) for recovery.
  • 🚫 Do not try to “drive” the thread with a tap - this may aggravate the problem.

Step 3: Check cylinder head flatness

If the head is deformed, it must be sanded. Allowable skew for Almera - no more 0.05 mm at length 100 mm. It is better to entrust grinding to specialists with pneumatic machine.

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If, after exceeding the torque, the engine starts but runs with vibration, check valve timing. The timing marks may have shifted due to head deformation.

FAQ: Frequently asked questions about cylinder head tightening torque Nissan Almera

Can cylinder head bolts from other Nissan engines be used?

No. Bolts are selected according to thread diameter, length and material. For example, bolts from SR20DE looks like bolts GA16DE, but have different thermal stability. The use of non-original bolts will lead to their elongation and loss of torque.

Do bolts need to be lubricated before tightening?

Depends on the type of bolts:

  • 🛢️ Standard bolts (for example, in GA16DE) - lubricated with a thin layer of engine oil to reduce friction.
  • ❌ TTY bolts (for example, in HR16DE) - lubrication is prohibited, as it distorts the calculated torque.
How often should the cylinder head torque be checked?

When assembled correctly no additional verification required. Exceptions:

  • After engine overheating (risk of head deformation).
  • If you have been noticed antifreeze leaks or oil in the cylinder head area.
  • After emergency repairs (for example, replacing a gasket in the field).
How are TTY bolts different from regular bolts?

Bolts Torque-To-Yield (TTY) are specially designed for plastic deformation when tightening. They are:

  • 🔧 Stretch to the yield point, providing maximum force.
  • 📏 They have strictly standardized elongation (for example, for QR25DE - no more 0.2 mm).
  • 🚫 Not reusable.

Regular bolts operate in the elastic zone and can be reused (but not recommended).

Which cylinder head gasket is better to choose for Almera?

Recommended options:

  • 🥇 Original Nissan (part number depends on the engine, e.g. 11044-JM00A for GA16DE) - best quality, but high price (~3000 rubles).
  • 🥈 Febi or Elring - worthy analogues (~1500 rubles), meet OEM standards.
  • ❌ Avoid cheap gaskets without reinforcement (for example, "noname" from China) - they burn out after 10–20 thousand km.