2003 Johnson 150 problem

tcooper

Recruit
Joined
Jul 7, 2003
Messages
2
Ran fine for about 3 weeks. Has developed a problem when running over 4,100 rpms engine will lose power. Never stalls or misfires, just slows down like the timing is retarding. When engine slows down fuel ball is normal, tried pumping it, no change. Put vac gauge on fuel supply line, never exceeded 2 inches. Tried pushing key to prime position when problem is occuring, no change. Looking into carbs when problem starts, no visible change in the amount of fuel being drawn. Attached inductive timing lite to each plug wire when problem is happening, flashes on all cylinders. Suspect module is retarding timing, but the problem is quite predictable and seems to occur at all engine temps, from cold to hot. I am an automotive tech, and most module type failures I have encountered have not been as consistant and are usually affected by temp. Any help would be great. My local dealer has a four week backlog before he can even look at it, I'm hoping I can speed up the process.
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,657
Re: 2003 Johnson 150 problem

You may want to try emailing Johnson/Bombardier directly. They may have a tech bulletin on it. Or may be hearing about same problem from others.
 

rabidfish

Senior Chief Petty Officer
Joined
Oct 3, 2000
Messages
788
Re: 2003 Johnson 150 problem

To what rpm does the engine slow down to? Does your warning horn beep when you turn on the key?<br />Does any lights come on on your "system check" gauge? Do you have a system check gauge?
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: 2003 Johnson 150 problem

Is this a BOMB or OMC buildt engine?
 

MIKE F

Petty Officer 1st Class
Joined
Aug 30, 2001
Messages
313
Re: 2003 Johnson 150 problem

clanton, you're slipping :D <br />You've got to know, that since this is a 2003 engine, it has to be a Bomb. ;)
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: 2003 Johnson 150 problem

You never know, and I have not looked at many 2003, and I dont know all of the changes the BOMB made. I am working on new information sources to bring self up to speed on the new stuff. IF this was 2000/2 engine, I would look for trash in the float bowl, needle and seat. You can drain the carb fuel into cup, look for small black spec and small aluminun shavings. I still dont know where the aluminun shavings come from, VRO pump, fuel tank, and the filter should catch it comming from both points. Check coils for arcing to metal plate that covers power pack. You could put meter on input to coil and check voltage while running at the problem rpms. I for get the specs, but all 6 cylinders should be with 8-10 volts of each other on the AC scale. Pack and sensor is probley bad.
 

tcooper

Recruit
Joined
Jul 7, 2003
Messages
2
Re: 2003 Johnson 150 problem

If I leave the throttle at full, the engine will slow down to about 2500 to 3000 rpm. If I reduce throttle to about 1500 then accelerate, engine will run normally until it reaches above 4100 for a few seconds. All lites and warning horns seem to be working in a normal fashion, beep and flash when I turn on the key, then remain off. After checking for spark with the timing lite, I replaced the plugs, thinking I may have fouled them during the breakin period. I also checked the fuel filter in the engine, no problem found. Could the module be breaking down When the load on the primary increases? Seems strange that the problem is not progressing. Anyway, thanks for your thoughts, I guess I'll have to wait for my local dealer to take a look.
 
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