1992 120 Johnson not getting up.

[James R]

Has a new power pack nice blue sparks. Starts and idles nicely. Motor is rebuilt with new fuel pump etc. Goes up to around 2000 and then sputters out. Below 2000 runs fine. Tach dies around 2000.
Need help guys.

 

[Will Bark]

Re: 1992 120 Johnson not getting up.

Hi speed jet clean? Link and sync correct? Tach sounds electrical. CDI website may give some direction. Gurus should chime in. Good luck

 

[James R]

Re: 1992 120 Johnson not getting up.

Thanks for the response WB. Carbs are clean and rebuilt.
Further research shows that this motor, if it goes to overheat or if a sensor is defective, will slow down and not permit more than 2000RPM.
This I need to look at when the boat gets back to me.
I note that there is a different water hose arrangement on this one compared to others. Perhaps someone can explain what the aspirator, aspirator valve and water intake hose system does and how it works. This may have an effect on water flow and temperature.
Also noted that there appears to be no water coming out of the two rear vents. I would expect to see some.
Thanks all.

 

[boobie]

Re: 1992 120 Johnson not getting up.

What happens If you hit the choke when this happens ??

 

[James R]

Re: 1992 120 Johnson not getting up.

Checked the motor and no overheat. Learned that there was no charging evident and that the Tach would not come up.
Replaced the rectifier/regulator with a new CDI unit and all is well. We did the choke test earlier with no change.
I have found out that this motor has the " high pressure cooling system" whatever that is but as there is no overheating my concern that there is little water coming from the rear two vents is of no consequence. Thermostats open normally. Motor runs very well.
Thanks for all the help and interest guys. Keep it coming.