ENGINE HEAD REBUILD

This part of the engine usually suffers from breakdowns once they occur. We provide complete overhaul services for all types of cylinder heads, from passenger to industrial types of engines heads.

What is a cylinder head and what is its role?

Cylinder head is the upper part of the engine. It rests on the engine block to close the compression space of the cylinder, the place where the engine burns fuel and produces power. Engine head contains valves that are responsible for the flow of the air. The intake valves draw in the fresh air, and on that occasion, combustion occurs, and then the exhaust valves allow the mixture of burned air to come out of the combustion chamber.

The difference with cylinder heads can be primarily in the materials used to make them. In newer types of engines, aluminium is the most commonly used material, while in older types of engines, cast iron was the more popular choice.

How does a hazard occur and how is it resolved?

The causes of engine head breakdowns can be different and most often occur:

As a consequence of poor maintenance of the vehicle. Not servicing your vehicle at the scheduled time or not changing the timing set when it needs to be replaced can lead to severe consequences. Timing belt or chain make the connection between the lower part of the engine (block) and the upper part of the engine (head). They may break due to wear, and then, by closing the connection (phase), the pistons located in the engine block hit the valves located in the engine head, bend or break them. In such situations, the engine shuts down.

Due to poor engine lubrication. Poor engine lubrication can be the result of irregular oil and filter changes. As a result, we can see the oil channels and oil pressure regulator in the engine become dirty, or the oil pump malfunctions. As a result, moving parts in the cylinder head such as the camshaft, valve lifters or rocker arms may get damaged.

If a breakdown occurs, what are the symptoms and what are the next necessary steps?

In the event of major and instantaneous engine head failures, the engine will stop running. The causes of accidents can be different. Therefore, the symptoms are the same. We can recognize some cases that gradually lead to damage of parts in the engine head, and later to accidents. These are different changes in engine operation. They are sometimes manifested by a loss of engine power, often by a change in the sound of engine operation in which various “knocks, taps, etc.” can be recognized. If we recognize any of these changes, it is necessary to inspect the vehicle by a service technician(mechanic) to determine further procedures.

Available operations are:

Pressure testing
Surface grinding
Valve seat cutting
Valve seat replacement
Production and replacement of injector seats
Thread replacement

Valve guide and seal replacement
Valve adjusting
Alloy welding
Broken thread rod extraction
Extraction of broken injectors
Camshaft housing line boring

Check out our processes.

WORK ORDER CREATION

In order to speed up the process of finding adequate spare parts, we advise you to prepare the engine number of your car. It can be found in your vehicle's license card. (Only for Serbian clients).

ENGINE HEAD DISASSEMBLY

The first step is to disassemble the cylinder head. During disassembly, we can see the first causes of the accident as well as damage to the cylinder head.

FIRST WASH

To give an accurate review, the process of cleaning the cylinder head is the next step. The cylinder head is washed in special machines (ultrasonic tubs) to remove deposits of crusty oil. Some heads are also sandblasted.

PRESSURE TEST

Pressure test involves testing the cylinder head for cracks in the material. If present, the head must be repaired (welded) before continuing the overhaul process. During the hydro-test, the head is immersed in the testing machine at a temperature of 90 ° C

VALVE HEAD GRINDING

Before the process of valve grinding, the wear of the stem is first checked. After that, the valve is grinded. Based on these operations, we determine whether the valves are still usable. If they are not, they are replaced with new ones.

VALVE GUIDE REPLACEMENT

The role of the valve guide is to keep the valves in perfect alignment with the valve seat. Their second role is to conduct heat during the combustion process through the exhaust valves. They change when there is too much clearance between the valve stem and the guide wall.

VALVE SEAT CUTTING

In order to obtain an ideal fit of the valve head onto the valve seat, the process of cutting (milling) of the valve seat is performed. This process achieves the ideal sealing of the valve on the cylinder head.

RESURFACING

It is of crucial importance that the cylinder head and cylinder block fit ideally one on top of the other. Sealing these two parts to have factory application is a must, thus the block surface must be ideally flat.

FINALNO PRANJE

Nakon završetka svih procesa mašinske obrade, glava motora prolazi kroz fazu finalnog pranja. Ovom prilikom uklanjaju se novonastale nečistoće od mašinske obrade i zatim sledi farbanje.

FINAL WASH

After completing all machining processes, the cylinder head goes through the final washing phase. On this occasion, the newly formed impurities are removed from the machining, and then painting follows.

ASSEMBLY

This is the final phase of the cylinder head overhaul. At this phase, all parts of the engine head are mounted, and if the head is without a hydraulic valve tappet, then it is adjusted in manually to achieve uniform engine operation.

FINAL CONTROL

After the cylinder head has been assembled, we proceed with final inspection to establish discover potential omissions if they have occurred. Firstly we check if the valves hold using the vacuum test, and then the quality of the finishing as well as the aesthetic standard we stand behind.

PACKAGING

Finally, each repaired part of the engine is packed in a protective bag to prevent foreign bodies from entering the treated part. Inside the package you can also find our warranty card / measuring sheet with the exact machining measures.