HISSEN brings reconditioning of four stroke cylinder covers to a higher level by welding the corroded or worn seat pockets, sealing face and bring back to standard dimensions.
 
After a certain lifetime cylinder heads are subject to corrosion attacks in exhaust seat pockets and starts cooling water leaking to the engine, exhaust gases to the cooling system.
 
For slight corrosion, the pockets can be oversized by machining, to first, second or even third oversize, but finally it comes to an end.
 
If done properly, then the repaired area is liquid ad gas tight. We have successfully applied water pressure up to 12 bar (174 psi) to a test piece that was repaired by metal stitching.
 
We have developed a procedure to weld the pockets, bring them back to standard size again and with full functionality.