mthompson10744
New member
Hello to all , I'm currently having an issue with my 1989 Johnson 40hp . Boat struggles to start occasionally but my big issue is that I can't hold WOT for more than 30-45 seconds. Coming out of the no wake around 1k-2k rpm it is fine but as soon as I push past 4k rpm the engine will run strong for that 30-45 seconds and then spit and sputter sometimes it will die if I don't back out of the throttle. Sometimes the engine will just "pulse" and "lag" around 2k rpm if I stay in the throttle and it doesn't die.
Just bought the boat in June and I've had the problem since first time out on the water. So far I changed fuel tank(brand new 12gal), new fuel filter and primer bulb, rebuilt carbs(floats are adjusted properly) and I replaced the plugs. I inspected reed valves while carbs were off they were fine. I just ordered a new ignition coil, plug wires and new plugs.
I'm wondering if something inside the VRO pump could be causing this ? The engine was converted to premix long before I got it. The oil tank is gone and everything appears to be sealed up air tight I don't believe I'm sucking air . I plan on replacing all the fuel lines on the carb/vro as they are still old. I'm not sure how old the VRO pump is so I'm curious as to if it could be playing a factor ? I plan on also doing a compression test this weekend .
Any else wanna throughout suggestions? I greatly appreciate it!
Thank you
Just bought the boat in June and I've had the problem since first time out on the water. So far I changed fuel tank(brand new 12gal), new fuel filter and primer bulb, rebuilt carbs(floats are adjusted properly) and I replaced the plugs. I inspected reed valves while carbs were off they were fine. I just ordered a new ignition coil, plug wires and new plugs.
I'm wondering if something inside the VRO pump could be causing this ? The engine was converted to premix long before I got it. The oil tank is gone and everything appears to be sealed up air tight I don't believe I'm sucking air . I plan on replacing all the fuel lines on the carb/vro as they are still old. I'm not sure how old the VRO pump is so I'm curious as to if it could be playing a factor ? I plan on also doing a compression test this weekend .
Any else wanna throughout suggestions? I greatly appreciate it!
Thank you