Hi Everyone,
I'm new to the iboats forum. I have a 2004 Mercury 115HP 4 Stroke EFI outboard. I'm usually pretty good with the maintenance. I do the following every year before the winter hits:
Change engine oil and filter
Add stabilizer to any remaining fuel
Change the fuel water separator
Clean the in-line filter (before the low pressure fuel pump)
Replace the lower gear oil
Remove the plugs, add Marvel Mystery oil and manually turn the flywheel, replace plugs
Remove and regrease the prop
Grease all the fittings
Spay all the exterior metal with anti corrosion spray
I use the boat in salt water so after every trip (it's trailered) I spray the boat and engine down with fresh water, and also flush the motor with fresh water.
I do a lot of trolling (low speeds), when I travel between fishing spots I usually cruise at about 20knots (4000 RPM). WOT is about 30knots at 5500 RPMs.
This year I am having the following problem with my motor. When I first took the boat out it seemed fairly normal, started right up, idled normally, and seemed rather normal (although it seemed a little rough) cruising at about 5 mph through the extensive no wake zone.
After passing the no wake zone, I pressed on the throttle and the engine was running very rough (shaking) and the boat WOT would only get up to about 10 knots. I couldn't even get up on plane.
I brought the boat back home and checked the spark plugs. Two of the plugs looked like they may have been carbon fouled (probably all the trolling). I replaced all the plugs and took the boat out for a test drive. The performance improved (WOT about 15knots) and I was able to get up on plane, however, it was still running rough and not even close to the power it should have. My Tachometer is not working at the moment, but the engine sounded like it had low RPMs at WOT.
I tried the fast idle, it makes a lot of noise but I'm not sure if that could tell me anything.
Any help would be greatly appreciated.
I'm new to the iboats forum. I have a 2004 Mercury 115HP 4 Stroke EFI outboard. I'm usually pretty good with the maintenance. I do the following every year before the winter hits:
Change engine oil and filter
Add stabilizer to any remaining fuel
Change the fuel water separator
Clean the in-line filter (before the low pressure fuel pump)
Replace the lower gear oil
Remove the plugs, add Marvel Mystery oil and manually turn the flywheel, replace plugs
Remove and regrease the prop
Grease all the fittings
Spay all the exterior metal with anti corrosion spray
I use the boat in salt water so after every trip (it's trailered) I spray the boat and engine down with fresh water, and also flush the motor with fresh water.
I do a lot of trolling (low speeds), when I travel between fishing spots I usually cruise at about 20knots (4000 RPM). WOT is about 30knots at 5500 RPMs.
This year I am having the following problem with my motor. When I first took the boat out it seemed fairly normal, started right up, idled normally, and seemed rather normal (although it seemed a little rough) cruising at about 5 mph through the extensive no wake zone.
After passing the no wake zone, I pressed on the throttle and the engine was running very rough (shaking) and the boat WOT would only get up to about 10 knots. I couldn't even get up on plane.
I brought the boat back home and checked the spark plugs. Two of the plugs looked like they may have been carbon fouled (probably all the trolling). I replaced all the plugs and took the boat out for a test drive. The performance improved (WOT about 15knots) and I was able to get up on plane, however, it was still running rough and not even close to the power it should have. My Tachometer is not working at the moment, but the engine sounded like it had low RPMs at WOT.
I tried the fast idle, it makes a lot of noise but I'm not sure if that could tell me anything.
Any help would be greatly appreciated.