malibu mascoma
New member
I have 200 hp mariner outboard, 1996, EFI, 6 cylinder. This spring it started acting up. Felt like it was running on 4 cylinders or only on one bank. I changed two fuel filters and rebuilt the low pressure fuel pump. Service manual suggested it was electronic. I first tried replacing one of the two switch boxes. When the new switch box made no difference I took the removed one and used it in place of the one not replaced. No change. Further diagnostic suggested it may be the stator or trigger. Replaced both. Stator was bad after running ohms tests on it. This did not solve the problem entirely. Had marine mechanic run additional tests including compression tests (all cylinder good 120-130 psi), verified all cylinders were firing at idle and high rpms. checked cylinder firing with strobe and all are firing. Mechanic felt/thought that the voltage regulators may be bad, replaced both. Runs better but no power over 2500 rpms. It will develop rpms (5000) and max speed of about 35 and occasionally take off and run perfect. Should have speed of 55 mph at 5,000 rpms. Cuts in and out ( runs perfect and then drops off). I am thinking that the timing is not always advancing over 2500 rpms. Any thoughts on what is still wrong?
