fastjeff
Gold Medal Contributor
After five years running a total of three Edelbrock 1409 carbs in my 32 Marinette, I have come to the following conclusions:
They do NOT flood (unless one ignores proper fuel filtration methods).
They do NOT backfire when the throttle is juiced (unless the idle mixture is too lean—see below).
Perhaps it is just my boat, but after sitting a week or so both carbs are empty of fuel; I had to install an electric boost pump system to avoid cranking the starters and ring gears to death.
After years of running all three of these carbs slowly developed a lean idle mixture condition that enrichening the idle mixture screws could not alleviate. From the customary 1 ½ turns out to 4 plus (and it makes no difference after that many turns out) each of the 3 carbs (one used, two new) exhibited this trend. The result is stalling, rough running at idle in gear, and frustration.
Port engine: On my used carb, I drilled the .060 inch holes the idle mixture needle goes into out to about .092. That cured the problem, but that carb had other issues so it became spare parts. Its replacement—the newest of the three--is struggling to maintain a proper idle at 3 ½ to 4 turns out, so it will need help soon.
Starboard engine: This, the oldest of my carbs, is running so lean it stalls every time I shift it into gear. (Runs perfect above 1,200 rpms, however.) I pulled her down for a thorough cleaning and was stunned to see black sediment—a lot of it—in the floor of the carb. I suppose it was also plugging the tiny idle feed passages as well; we’ll see.
Jeff
They do NOT flood (unless one ignores proper fuel filtration methods).
They do NOT backfire when the throttle is juiced (unless the idle mixture is too lean—see below).
Perhaps it is just my boat, but after sitting a week or so both carbs are empty of fuel; I had to install an electric boost pump system to avoid cranking the starters and ring gears to death.
After years of running all three of these carbs slowly developed a lean idle mixture condition that enrichening the idle mixture screws could not alleviate. From the customary 1 ½ turns out to 4 plus (and it makes no difference after that many turns out) each of the 3 carbs (one used, two new) exhibited this trend. The result is stalling, rough running at idle in gear, and frustration.
Port engine: On my used carb, I drilled the .060 inch holes the idle mixture needle goes into out to about .092. That cured the problem, but that carb had other issues so it became spare parts. Its replacement—the newest of the three--is struggling to maintain a proper idle at 3 ½ to 4 turns out, so it will need help soon.
Starboard engine: This, the oldest of my carbs, is running so lean it stalls every time I shift it into gear. (Runs perfect above 1,200 rpms, however.) I pulled her down for a thorough cleaning and was stunned to see black sediment—a lot of it—in the floor of the carb. I suppose it was also plugging the tiny idle feed passages as well; we’ll see.
Jeff
