Johnson 200 Oceanrunner, check engine alarm and low rpm

[Jason Edwards]

I recently bought a 2000 23' Promaster with a Johnson 200 Oceanrunner. The boat and motor have had nearly no use with the engine only having 20 hours on it. When using this boat it seems as if it has plenty of low end power but lacks top end rpm's. I could only milk 5000 rpm out of this engine and 40 mph trimmed out. The previous owner said this boat would do 48-50 mph no problem. What should this engine be revving at, 5000 rpm seems way to low.

My second concern is when running full throttle (at 5000 rpm's) and completely trimmed out to get the most mph the check engine alarm sounds. The alarm emits a solid noise, no beeping. I pull back to an idle and within 15 seconds the alarm quits. The only time the alarm will sound is when the boat is at top speed. I only notice the alarm when the motor is trimmed up to get the most speed. Would the alarm sound if I had it trimmed up too much and it wasn't pumping water? I think maybe my alarm may be attributed to me pulling the motor too far out of the water to get the engine to rev higher than 5000 rpm. Thanks in advance for any help.

 

[rodbolt]

Re: Johnson 200 Oceanrunner, check engine alarm and low rpm

check your fuel system vacum, you have a restriction someplace,
its the high fuel system vacum that is triggering a solid tone with no RPM reduction and a check engine light and not an overtemp light.

 

[Jason Edwards]

Re: Johnson 200 Oceanrunner, check engine alarm and low rpm

A fuel restriction? What do you think I should do next and what is the best way to check my fuel system vaccum? Thank you very much!