Cylinder Head Repair Specification Example for Dealership Service: Sealed Unit
Cylinder Head Repair Specification Example for Dealership Service: Sealed Unit
This is a worked specification for cylinder head repair in a sealed unit programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The sealed unit version exists because the duty cycle on dealership service is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually premature wear on the first batch.

Example specification
| Item | Cylinder Head Repair |
|---|---|
| Application | Dealership Service |
| Version | Sealed Unit |
| Base material | ABS Plastic |
| Controlled dimensions | 5 key dimensions, recorded per lot |
| Tolerance band | ±0.1 mm |
| Finish | powder coated |
| MOQ | 1,000 pieces per specification |
| Sampling | 10 working days, 5 days per revision |
| Compliance | IATF 16949 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — ABS Plastic, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.

Processes involved
- CNC machining
- precision stamping
- cold forging
- heat treatment
- assembly line testing
- rubber vulcanisation
Where this example applies
Programmes that run sealed unit most often specify this build for dealership service. Related applications include city buses, three-wheelers, construction equipment, municipal fleets, rental motorcycles.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 4.0 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
How is packing specified?
Individual packing, inner box quantity and carton marking are confirmed at quotation stage so the cartons arrive ready for your warehouse.
Can you match an existing sample?
Send a sample and we will reverse-engineer the specification, then produce a counter sample for approval before any bulk starts.
Can the specification be held on file?
Yes. Once approved, the specification is recorded against your part number so a reorder reproduces the IATF 16949-compliant build instead of a fresh interpretation.
How long does sampling take?
Samples leave the factory in 10 working days, and each revision round adds about 5 days once you have seen the first piece.
Ask for the current catalogue and the specification sheet for this line.



