I'm looking for some help please, gents.
I recently picked up a 1981 Manatee center console powered by a Johnson 115. The model number is J115TLCIM, I've been under the impression that the engine is a 1981 model, but the model number decodes as 1978. I'm not even sure that matters much though, just seems odd. [EDIT - There is no question, the engine is an '81 model]
Anyways, the engine was tuned up within a few months of transferring ownership to me, and ran beautifully the first time I took it out on the water. I put 87 octane E10 in it with additives figuring I'd be fine, and have had nothing but problems since. I suspect that the problems I have now are directly related to this fuel, but am here to hopefully gain some direction for how to diagnose and repair myself.
The engine has a hard time idling after sitting. It will fast idle, but wants to choke out when I lower the throttle lever, this is in neutral, either on the water, or on the flusher in the driveway. I was on the water a couple weeks ago headed to the first cove we like to fish at around 2/3 throttle (no tach) and it was like someone flipped a switch. Suddenly the boat slowed waaayyy down, and I wound up with the hammer all the way down just to keep the engine running. We went straight back to the launch, barely making a wake, with the engine seeming to be bogged down at around maybe 1000 RPM or so, and as soon as I brought the throttle back up to dock, the engine cut out.
I pulled the plugs at home, and felt a good puff of air out of all 4 holes. All plugs showed signs of combustion. It made me think I didn't have to worry about low/no compression and that I could rule those out as causes to the problems its giving me.
This past weekend, I pumped all of the fuel out of the main tank, and sucked it out of the line from the tank to the fitting on the engine. Filled with fresh, pure 87 octane unleaded and Johnson/Evinrude 2 stroke @ 50:1, and got the engine seemingly ready to work. The only thing that seemed off was an apparent delay in revving up to fast idle on the muffs. It eventually idled nice and smooth in the driveway. I put the boat in the water and SAME THING...it didn't want to idle. When it did finally idle, it cut out when I went to reverse away from the dock. I eventually got away from the dock, and running well enough to move forward, and same thing, it would not rev up, and would not push the boat faster than say 5 mph or so. It seems like I have carburetion problem(s), but I really have no idea.
Does this sound familiar to you? Can you offer any insight or direction to help me get this thing running right? Thanks in advance for any advice, guys...
I recently picked up a 1981 Manatee center console powered by a Johnson 115. The model number is J115TLCIM, I've been under the impression that the engine is a 1981 model, but the model number decodes as 1978. I'm not even sure that matters much though, just seems odd. [EDIT - There is no question, the engine is an '81 model]
Anyways, the engine was tuned up within a few months of transferring ownership to me, and ran beautifully the first time I took it out on the water. I put 87 octane E10 in it with additives figuring I'd be fine, and have had nothing but problems since. I suspect that the problems I have now are directly related to this fuel, but am here to hopefully gain some direction for how to diagnose and repair myself.
The engine has a hard time idling after sitting. It will fast idle, but wants to choke out when I lower the throttle lever, this is in neutral, either on the water, or on the flusher in the driveway. I was on the water a couple weeks ago headed to the first cove we like to fish at around 2/3 throttle (no tach) and it was like someone flipped a switch. Suddenly the boat slowed waaayyy down, and I wound up with the hammer all the way down just to keep the engine running. We went straight back to the launch, barely making a wake, with the engine seeming to be bogged down at around maybe 1000 RPM or so, and as soon as I brought the throttle back up to dock, the engine cut out.
I pulled the plugs at home, and felt a good puff of air out of all 4 holes. All plugs showed signs of combustion. It made me think I didn't have to worry about low/no compression and that I could rule those out as causes to the problems its giving me.
This past weekend, I pumped all of the fuel out of the main tank, and sucked it out of the line from the tank to the fitting on the engine. Filled with fresh, pure 87 octane unleaded and Johnson/Evinrude 2 stroke @ 50:1, and got the engine seemingly ready to work. The only thing that seemed off was an apparent delay in revving up to fast idle on the muffs. It eventually idled nice and smooth in the driveway. I put the boat in the water and SAME THING...it didn't want to idle. When it did finally idle, it cut out when I went to reverse away from the dock. I eventually got away from the dock, and running well enough to move forward, and same thing, it would not rev up, and would not push the boat faster than say 5 mph or so. It seems like I have carburetion problem(s), but I really have no idea.
Does this sound familiar to you? Can you offer any insight or direction to help me get this thing running right? Thanks in advance for any advice, guys...
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