Hi All,
I've been lurking for years and am usually able to find any and all info I need without posting my exact situation but that seems to have changed with this latest motor.
1996 Johnson 50hp 2 stroke 3cyl J50DTLEDC
So here's the issue. I bought the boat at the end of last season, ran fine for the two times I had it out that year, did some regular maintance on it (plugs, lower end fluid, fuel filter) and took it out again....no issues. Went on a fishing trip, and by this time I had finally ran the old gas out of it so I filled it back up with 91 (ethanol free) and headed 4 hours up north for my trip. Boat ran fine for the first day and then half way into the second day it decided it didn't want to rev past about 3k. After some fiddling around trying to fix it on the water the only luck I had was that when I hit the primer button on the key it would hop up on plane and run fine for a few seconds. If I held it too long though it would stumble (flooding I assume).
At that point I assumed the issue was a plugged main jet or something on one or all of the carbs and didn't have time to deal with it so I took it too a marina kinda local to me and figured I'd let them deal with it.
I checked compression prior to bringing it in and all cyl were within 5% of each other
After two weeks I got the boat back with 3 rebuilt carbs and a new water impeller (old one was getting weak so I asked them to replace it while it was in), new fuel filter, and they apparently "checked the plugs"
Now yesterday I put it in the water, and immediately on startup I get a check engine light on the tach and an about 10 second alarm. The check engine light went off a minute or so later as I was deciding whether or not I wanted to take it out so I figured it was a reset issue. Passed through the no wake zone and throttled up, it jumped on plane so I thought all was good and then immediately stumbled to 2k - 3k rpm and the same crap that was happening before started again.
Once I stopped cursing the marina that obvously didn't actually diagnose the effing thing and just threw parts at it I started tearing into it myself. First thing was that I went out and got a portable fuel tank and new line and bulb to rule out an anti-syphon valve that could be in the onboard tank causing issues and took it back out....same issue.
Brought it back home, took off the top carb and opened it up thinking maybe I was lied too and they didn't actually do any work but it looks good, blew through the main jet and it seems to be clear but I don't have a screw driver small enough to remove it and really check. I removed the VRO and checked both diaphrams for any cracks, leaks, or rubber coming apart but it looks brand spankin new inside. I checked the fuel lines and there doesn't seem to be any cracking or weathering (new lines on order)
So now I have the same d*&n problem but with the addition of a check engine light on the tach that comes on as soon as the key is turned (prior to cranking) and an approximately 10 second long solid alarm after the engine starts but if I hit the primer it will still run great for a few seconds.
Help me please!!
I've been lurking for years and am usually able to find any and all info I need without posting my exact situation but that seems to have changed with this latest motor.
1996 Johnson 50hp 2 stroke 3cyl J50DTLEDC
So here's the issue. I bought the boat at the end of last season, ran fine for the two times I had it out that year, did some regular maintance on it (plugs, lower end fluid, fuel filter) and took it out again....no issues. Went on a fishing trip, and by this time I had finally ran the old gas out of it so I filled it back up with 91 (ethanol free) and headed 4 hours up north for my trip. Boat ran fine for the first day and then half way into the second day it decided it didn't want to rev past about 3k. After some fiddling around trying to fix it on the water the only luck I had was that when I hit the primer button on the key it would hop up on plane and run fine for a few seconds. If I held it too long though it would stumble (flooding I assume).
At that point I assumed the issue was a plugged main jet or something on one or all of the carbs and didn't have time to deal with it so I took it too a marina kinda local to me and figured I'd let them deal with it.
I checked compression prior to bringing it in and all cyl were within 5% of each other
After two weeks I got the boat back with 3 rebuilt carbs and a new water impeller (old one was getting weak so I asked them to replace it while it was in), new fuel filter, and they apparently "checked the plugs"
Now yesterday I put it in the water, and immediately on startup I get a check engine light on the tach and an about 10 second alarm. The check engine light went off a minute or so later as I was deciding whether or not I wanted to take it out so I figured it was a reset issue. Passed through the no wake zone and throttled up, it jumped on plane so I thought all was good and then immediately stumbled to 2k - 3k rpm and the same crap that was happening before started again.
Once I stopped cursing the marina that obvously didn't actually diagnose the effing thing and just threw parts at it I started tearing into it myself. First thing was that I went out and got a portable fuel tank and new line and bulb to rule out an anti-syphon valve that could be in the onboard tank causing issues and took it back out....same issue.
Brought it back home, took off the top carb and opened it up thinking maybe I was lied too and they didn't actually do any work but it looks good, blew through the main jet and it seems to be clear but I don't have a screw driver small enough to remove it and really check. I removed the VRO and checked both diaphrams for any cracks, leaks, or rubber coming apart but it looks brand spankin new inside. I checked the fuel lines and there doesn't seem to be any cracking or weathering (new lines on order)
So now I have the same d*&n problem but with the addition of a check engine light on the tach that comes on as soon as the key is turned (prior to cranking) and an approximately 10 second long solid alarm after the engine starts but if I hit the primer it will still run great for a few seconds.
Help me please!!
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