Nissan Cylinder Head TB42 semi assembly 171326
171326This Nissan TB42 cylinder head semi assembly (171326) fits the TB42 petrol platform and sits as a direct replacement for worn or cracked heads. It comes ready for the remaining valve gear, so workshops can set it up the way they prefer. The casting lines up well with the TB42 layout, making it easier to finish the build and get the engine running again. It suits rebuilders, fleet operators, and anyone restoring an engine that has started losing compression, misfiring, or running rough.
This cylinder head sits on the TB42 engine and takes care of the top-end issues that usually show up after years of heat cycles, gasket failures, or long-term wear. Mechanics often replace the TB42 head when it starts cracking between seats or when one side of the chamber loses shape. This semi assembly saves time because the base work is already done, and the head is ready for the rest of the parts you want to install.
The casting follows the TB42 layout, so the ports, chambers, and bolt points line up the way they should. That matters when you’re rebuilding older engines, because even a small mismatch can cause sealing trouble or uneven firing. Another thing worth noting is how clean the machined surfaces sit — it makes the gasket sit flat, which helps the engine hold compression once everything is torqued down.
Why workshops pick this TB42 semi-assembly
- Fits the Nissan TB42 petrol engine without unusual adjustments
- Works well for engines that suffer from overheating or head distortion
- Lets mechanics set up their own valve gear and timing components
- Supports consistent compression and smoother combustion
- Helpful for complete rebuilds, partial repairs, or long-distance fleet maintenance
In most cases, technicians choose a semi assembly like this when they want control over the final setup but don’t want to start from a bare casting. It works for that. Once installed, the engine usually idles steadier and runs cleaner, especially if the old head had warped or started leaking around the gasket.
Acme Impex inspects the casting and machining before dispatch. The goal is simple: ship a head that sits right on the block and supports a clean rebuild. This TB42 semi assembly gives you a practical way to get the engine back into working shape without unnecessary complications.