pepperjackdaisy
Recruit
- Joined
- May 18, 2015
- Messages
- 1
Hi all. Just "married into" a 2003 Mercury 90 ELPTO that has been neglected for a few years. I'm a self-taught mechanically-minded guy, but by no means formally trained. Tinkering with old BMW's is my hobby, and have done a motor swap with the help of many online diy forums, so I can say my knowledge is above average. My only experience with 2 stroke motors is cranking the weed eater and chainsaw. The boat is running terrible at the moment. Here's where I started...
Originally, idling all over the place, too high, too low, surging, smoking, stalling, etc.
Removed and cleaned carbs, new plugs, new fuel filter, rebuilt fuel pump, replaced a couple of fuel lines, new primer bulb, fresh gas in tank.
Compression test, all 3 cylinders within 2 psi, 112-114.
and where I am now...
After all was completed, at first start, it was idling at 2000. I have bottomed out the main "idle adjustment" screw to get the idle down to manageable, but its still at 1000. Under load in water, it drops to around 700-800. This doesn't seem right, as the screw is literally bottomed out, can't turn it any more. Carbs are set 1.5 turns out from lightly seated.
Now I am getting a strange backfire every 10-20 seconds, sending a puff of smoke out from somewher behind the starter. This happens at any rpm. I'm at a loss. Any advice would be greatly appreciated. I have searched this forum and google using different word combinations and terms, but can't seem to find any information on this problem.
Originally, idling all over the place, too high, too low, surging, smoking, stalling, etc.
Removed and cleaned carbs, new plugs, new fuel filter, rebuilt fuel pump, replaced a couple of fuel lines, new primer bulb, fresh gas in tank.
Compression test, all 3 cylinders within 2 psi, 112-114.
and where I am now...
After all was completed, at first start, it was idling at 2000. I have bottomed out the main "idle adjustment" screw to get the idle down to manageable, but its still at 1000. Under load in water, it drops to around 700-800. This doesn't seem right, as the screw is literally bottomed out, can't turn it any more. Carbs are set 1.5 turns out from lightly seated.
Now I am getting a strange backfire every 10-20 seconds, sending a puff of smoke out from somewher behind the starter. This happens at any rpm. I'm at a loss. Any advice would be greatly appreciated. I have searched this forum and google using different word combinations and terms, but can't seem to find any information on this problem.
