SPECIALIST MACHINING FOR A DIESEL BLOCK PROBLEM

The following photos cover the repairs required after a corrosion problem at the upper sleeve registers and deck of a Misubishi 6D24 engine.

Bad Corrosion across the length of the block led to engine failure with two seized pistons, blown head gaskets, leaking injector sleeves and worn valve guides. A full job was done on the whole block assembly and the heads were reconditioned. The whole engine and head work was done in house.

The following following photos show other views of the job

Block has been surface ground to get the surface below the corrosion and fretting. All six upper sealing surfaces have been repaired and the sleeve registers dropped to provide the specified piston protrusion. This is a very exacting machining work and is only undertaken by experienced and skilled staff.

A Close up of the actual end result showing surface finishes with the corrosion damage "gone"

The weight of these large sleeves requires a great deal of care when working with them. During the machining, cleaning and trial assembly process, each sleeve is handled several times in and out of the block

The block has reached the final assembly stage showing the range of sleeve seals fitted over the sleeves ready for the careful assembly down into the block.

Sleeves successfully fitted

The CNC milling operation shown here is one of the four separate maching operations used to lower the top of the piston to match what had to come off the deck of the block. The piston crown has three valve reliefs; each with a different diameter. The amount removed has been established from a trial, or dummy, assembly of each piston into it's respective sleeve in the block . See below:

Pistons In :     

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