Tweet
Friend of a friend bought 2 Yamaha 250 HPDI engines surplus/ used from Charlseston, SC PD. Had a blown 225 OX66 he wanted to replace. Swapped one of the engines he was told was in running condition to his boat. Would not start. Used Yamaha diagnosis computer- got message not connected to EMC. All connections fine. Pulled rear shroud off to inspect ECM and found that 5 of the 6 coils were " exploded". They had been so hot they had cracked open housing and pushed out and leaked potting material. Went ahead and swapped out entire frame with ECM and injection con*****ers from second engine. Still will not start - still get diagnostic message that computer is not conected to ECM. No blown fuses- relays in spec- no visual damage to wiring harnesses . Any Ideas what could cause this ?