jackball42
Petty Officer 3rd Class
- Joined
- Apr 2, 2011
- Messages
- 76
I have a 1977 Starcraft SuperSport with a Mercruiser 140 I/O. When I mash down on the throttle it hesitates and even dies occasionly unless I pump the shifter and sometime backfires through the carb. I have been through the carb and verifed the float settings are correct and the accelarator pump is working correctly. The timing spec is 6 degrees BTDC and the idle spec is 650-700 in gear. To get the 650-700 in gear spec the idle while on the muffs must be about 775-800 and this causes the mechanical advance to advance the timing. I backed the idle down, while still on the muffs, to 700 and then adjusted the timing to 6 degress. It no longer hesitates as bad and does not back fire through the carb.
The dwell is at 32-34 degrees per spec.
Am I all wet in my thinking and will retarted timing cause the symptons I was seeing? I also saw another thread where Mercruiser changed the sped to 8 degrees at some point. I am running 91 octane gas because the 87 octane around here has 10% ethanol in it.
The dwell is at 32-34 degrees per spec.
Am I all wet in my thinking and will retarted timing cause the symptons I was seeing? I also saw another thread where Mercruiser changed the sped to 8 degrees at some point. I am running 91 octane gas because the 87 octane around here has 10% ethanol in it.