Nissan KA24DE Head Bolt Torque Sequence and Five Stages

How to use this specification correctly

1. 01

   Record model, model year, VIN, engine stamping and installation layout. Positively identify the DOHC KA24DE and exclude the SOHC KA24E; identify any swapped 240SX/truck head, aftermarket gasket or stud kit.

2. 02

   Set the crank and camshafts to the application manual's service position. Paint-mark the upper chain, cam sprockets, lower-chain/idler relationship and engine-front orientation before separating timing components.

3. 03

   With the engine cold, loosen head bolts in Nissan's published removal order over two or three gradual steps. Nissan warns that using the wrong order can warp or crack the aluminum head.

4. 04

   Clean the head and block without cutting the deck. Check the cylinder-head sealing surface with a reliable straightedge and feeler gauge in the specified directions; the cited Frontier data gives less than 0.03 mm standard and 0.10 mm service limit.

5. 05

   Clean and dry every bolt hole, dowel and oil/coolant passage. Verify the new gasket and any front-cover liquid-gasket bead against the exact vehicle manual; the 240SX and truck front/timing assemblies are not interchangeable instructions.

6. 06

   Inspect production fasteners for damaged threads, corrosion, necking and bearing-face damage. Replace questionable or unknown hardware. If using studs, stop here and change to the kit maker's lubricant and tightening sheet.

7. 07

   Apply a uniform light film of new engine oil to the factory bolt threads and seat surfaces. Hand-start all bolts and assign physical numbers from the correct Nissan illustration.

8. 08

   Tighten the complete numerical order to 29 N·m (22 lb-ft), then repeat it at 79 N·m (59 lb-ft). Log each completed position without adding a final torque check outside Nissan's procedure.

9. 09

   Loosen every main bolt completely as stage three. Reseat all bolts in the same tightening order to 25–34 N·m (18–25 lb-ft); choose and document one target within Nissan's range for consistent tool technique.

10. 10

    Using an angle wrench, repeat the order and turn each bolt 86–91 degrees clockwise. If using marks, place the initial line on the engine-front side and verify the final measured rotation. Install cams with dowels at 12 o'clock where specified, torque cam brackets in their separate order, restore the upper chain/idler and hand-verify timing.

Why Nissan tightens, releases and retightens

The first two torque stages seat the gasket, head and fastener interfaces under meaningful load. Releasing all bolts resets the joint after that initial seating cycle; the lower reseat torque establishes the baseline for the controlled final rotation.

This is one complete method. Do not omit the release because the bolts ‘already reached 59 lb-ft,’ and do not torque them back to 59 lb-ft after the angle. Both changes depart from the FSM and alter clamp load.

Using the 86–91 degree angle correctly

An angle wrench should be zeroed separately at each bolt after stage four. Keep the extension short and rigid, maintain socket alignment and complete the turn smoothly. A paint line gives a visual cross-check but should still be measured rather than judged casually.

Some older service summaries print a torque alternative when an angle tool is unavailable. The cited later truck manuals direct marking and turning through the angle, so that measured angular method is the safest common procedure for the applications documented here.

240SX versus Frontier and Xterra boundaries

The main five-stage values match in the cited S14 240SX and D22-era truck/SUV manuals. That agreement does not make the whole installation identical: timing-cover sealing, chain access, intake/exhaust removal and brackets differ with chassis and longitudinal packaging.

A transverse KA24DE or hybrid engine requires its own confirmation. Use matching service information for front-cover RTV placement, gasket interfaces, cam brackets and timing-chain marks even if the main-bolt stages prove the same.

Camshaft, idler sprocket and chain control

The truck manual places both camshaft dowel pins at 12 o'clock for cam installation, then torques cam brackets in a separate two-stage numerical order before restoring the upper chain and idler sprocket. Mixing caps or tightening them unevenly can damage the cam or head.

Preserve valve lifters and cam brackets in their original positions, lubricate sliding surfaces and verify colored/painted timing references after tension is applied. Hand rotation and a second timing check must precede starter operation.

KA24DE head-installation checklist

• Vehicle/year/layout and KA24DE code confirmed
• KA24E and unsupported variants excluded
• Application FSM sequence figure visible
• Engine-front orientation marked
• Timing chains and sprockets indexed
• Head bolts released in gradual correct order
• Head/block measured for flatness and damage
• Bolt holes and passages clean and dry
• Correct gasket/front-cover sealant procedure selected
• Factory bolts inspected or replaced
• Threads and seat surfaces uniformly oiled
• 29 N·m pass logged
• 79 N·m pass logged
• All bolts fully released
• 25–34 N·m reseat pass logged
• 86–91° pass measured and logged
• Cam caps and chains completed separately
• Engine hand-rotated and timing rechecked