6D24 Diesel Used Engine Blocks For Excavator HD1430 - 3 SK480 -6 ME152652

Specification

Description

repair technique

Small porosity leaks in aluminum can often be easily plugged with a single pin or tapered plug. Cracks in an aluminum head or block, on the other hand, are much more difficult to repair by pinning because aluminum is a softer metal than cast iron so the pins and plugs can’t achieve as much “bite” as they do in an iron casting. Pinning can provide a satisfactory repair on small cracks in non-stressed areas but are usually not recommended for large cracks or cracks near the valve seats. Welding is usually the preferred repair technique because aluminum is relatively easy to weld compared to cast iron. A TIG welder with an argon or helium gas supply can fill in most cracks easily and quickly.

Another cold repair technique that can be used on areas that are outside the combustion chamber or on exterior casting surfaces is to fill cracks with a high temperature epoxy. Many epoxies can provide a strong and long-lasting repair. Metal-filled epoxies may even be drilled and tapped to restore broken bolt bosses. The key to using epoxies correctly is to make sure the surface of the metal is perfectly clean, dry and free of any oil or coolant. The surface should also be slightly roughened by grinding or sand blasting so the epoxy can adhere to the surface. Most epoxies will set fairly quickly (15 minutes or less) but typically take 24 hours to fully cure.

Pinning Techniques

diesel_repair_2Different types of threaded pins or tapered plugs can be used for crack repairs. Use aluminum pins on aluminum heads and blocks, and cast iron or steel pins on cast iron heads and blocks.

Straight threaded pins are installed by drilling, tapping and screwing in overlapping pins. The holes for adjacent pins are drilled to overlap slightly, which helps lock each pin in place. The best results are often achieved by starting in the center of a crack and working towards the end of the crack as opposed to starting at one end of the crack and working towards the other end. Starting in the center helps spread the stresses outward as you work toward each end of the crack.