Home › Forums › Bass Cat Boats › Mercury 200 EFI, no power.
Common power loss problems with Mecury 200 EFI? (Your vote has been cast.)Total votes: 8 Fuel pump? 1(13%) ignition Coils? 3(38%) Fowled spark plugs? 4(50%)I recently purchased a 2003 Pantera classic with a 2003 200 mercury EFI. The motor required overhauling, had the pistons replaced and bored out. Took it out the first time and it ran fine. Now I cant get it on a plane. It idles good and revs up good in neutral and out of water. Tried to accelerate and it just bogs down, not getting over 2500 rpms. Had it in the shop and mechanic checked the computer and was unable to see any senors or alarms that could be detecting the problem. The problem seems to happen only under a load. Any ideas what the problem could be?
Forgot to add that I replaced the fuel line from the tanks to the motor. Fuel lines under the cowling appear to be good and see no crimps or kinks. Also replaced the fuel/water separator filter.
Was acting up before I changed the line and bulb. U know if there are any more fuel filters on the fuel lines anywhere? The new gas line I installed connects to a metal, prob brass, gas tube from both tanks so those cant be crimped.
Id take it to a trusted well known Mercury tech. Even if you have to tow it a long way, it will be worth it. If I had issues with my Merc…Id drive the 5 hours to Regal Marine, or go all the way to Sherms, 13 hours from here. You cant put a high enough value on a top notch outboard tech.
Just went througgh this last week found one reed block busted up
Had the exact same problem, mine turned out to be the wiring harness had a “loose/shorted” out pin that went to the fuel pump. you could start it fine, rev it up as much as you wanted to but when in gear and moving the “vibrations” would cause the pin to “short out” and not send the signal to the fuel pump. Wouldnt get on plane and if you stayed on it, it would almost die. This was on a 150 (small block) and was told that the wiring harness for the small blocks were made in mexico. Your Signature …
Catmantwo, wouldd u do to fix it?
The Merc tech at my Bass Cat dealer diagnosed the problem when he couldnt find any problems on the computer. He took the boat out on the river with the computer hooked up and ran it.It did exactly what I told him it would do. He said it was definitely a fuel delivery problem. I had them change the fuel lines (3 months earlier). Since fuel flow was good at idle, he looked at other possible problems. When he examined the wiring harness he noticed the bad pin, and replaced the pin himself. It has run great since, that was 7 months ago.They were kind enough to not charge me for their work (Performance Plus Marine).It might not be whats wrong with yours, but its worth looking at since is sounds real similar.Jim Your Signature …
Get a spray bottom with 50/50 mixSpray the premix fuel into hole in the EFI air silencer (the cast box on the front of the motor).If the motor takes off, it would be a fuel delivery problem.I have once pinched a fuel hose to a carb when reassemble a power head. It is easy to do.Another time I modified an engine so that 55D jets would not put enough fuel to the motor.I held my hand over the carb bores (like a choke butterfly) and choked off air to get it to run.With a few trial and error I found that I need #72 jets.
If you havent already, check the cannon plug. Some times they will virate/loosen up.
© 2026 Bass Cat Boats

