Background to The Repair
Our customer had a failure of a Jenbacher engine block where a con rod had rattled around the engine damaging a bearing cap, an oil gallery and a lower liner land. Nicol & Andrew were called in to carry out a dimensional survey to establish the extent of damage and to recommend a repair procedure.
Caption; Damaged Oil Gallery
The oil gallery had been crushed and cracked whichwould require an extensive repair. The lower liner land area had large areas of impact damage and would require boring oversize and sleeving. Two cam bearing pockets were also damaged and required boring and sleeving.
Caption; Damaged Lower Lining Landing
Repair to Oil Gallery
We ground out the oil gallery to remove the damaged section. We then reamed the bore to produce a good size and finish to accept a precision thin wall tube. We manufactured the thin wall tube in our workshops (with a slight interference fit), pressed it into position and secured it with Loctite. The surrounding area was then built up with liquid metal to match the existing profile.
Caption; Refurbished Jenbacher Bearing Cap
Repair to Lower Liner Landing
We mounted a line boring machine (Climax BB5000) in the top liner landing utilising a special precision mount referencing the undamaged bore. We then bored the landing oversize and fitted a precision sleeve (grub screwed) into position.
Repair to Caps
The caps were welded, stress relieved, machined, optically aligned and re-bored to standard size.
Repair to Cam Bearing Housing
We mounted a line boring machine (Climax BB5000 with small bore kit) referencing the original cam bores either side of the damaged locations. We then machined the bores oversize and manufactured and fitted make up sleeves.
Caption; Repaired Landing & Oil Gallery