peanutbay1
Petty Officer 3rd Class
- Joined
- Jun 4, 2009
- Messages
- 91
Re: OMC 5.0 surges after 4100 rpms (6/12 UPDATE)
Re: OMC 5.0 surges after 4100 rpms (6/12 UPDATE)
Engine compression is 165psi all 8 cylinders and vacuum is steady @19.My mechanic now sais the engine is fine but I have fuel or electrical issues.DAh!! thats why I paid him to dyno and tune the engine. Any way the bottom line is he is saying my new seirra electronic ignigtion conversion sucks and he would take it off and go back to points. I have discovered that when I put the new ignition in to the exact position of the original that it is in the clockwise position rather than CC which is how my distributor rotates. If I switch it to where it should be it wont run which proves the previous owner installed and timed the ignition incorrectly. I am going to position the trigger plate to CC and have the motor timed. The other issue I found out was that sierra sais you can NOT install there ignition with an OMC with shift interupt. I replaced exactly what ignition was in the boat but that does not make it right. Will this affect WOT or just shifting in and out of gear. On the fuel side I have watched the carb as the boat is under way and pushed the choke shut and it actually bogs the motor down which I would think means the boat is not to lean. I also would describe the plugs as grey ,not white (lean) or black (rich) just kind of in the middle. Any thoughts ???
Re: OMC 5.0 surges after 4100 rpms (6/12 UPDATE)
Engine compression is 165psi all 8 cylinders and vacuum is steady @19.My mechanic now sais the engine is fine but I have fuel or electrical issues.DAh!! thats why I paid him to dyno and tune the engine. Any way the bottom line is he is saying my new seirra electronic ignigtion conversion sucks and he would take it off and go back to points. I have discovered that when I put the new ignition in to the exact position of the original that it is in the clockwise position rather than CC which is how my distributor rotates. If I switch it to where it should be it wont run which proves the previous owner installed and timed the ignition incorrectly. I am going to position the trigger plate to CC and have the motor timed. The other issue I found out was that sierra sais you can NOT install there ignition with an OMC with shift interupt. I replaced exactly what ignition was in the boat but that does not make it right. Will this affect WOT or just shifting in and out of gear. On the fuel side I have watched the carb as the boat is under way and pushed the choke shut and it actually bogs the motor down which I would think means the boat is not to lean. I also would describe the plugs as grey ,not white (lean) or black (rich) just kind of in the middle. Any thoughts ???
Anyway, I'm not sure that pertronics would work with an OMC shift interupter, because I think it temporarily shorts out certain spark plugs when shifting? (maybe someone else can help with this?) It sounds like your plugs are firing fine, when they fire? One more thing, is your mechanical spark advance under the breaker plate working ? Can you turn the rotor any direction by hand with the engine off, it should rotate a bit, then rebound back under light spring pressure.