1992 Mercruiser 3.0 acceleration issue

gucio1

Seaman Apprentice
Joined
Aug 17, 2020
Messages
38
Hi guys,
I am back with another issue. I guess that is the part of the fun ow owning a 30 year old boat :)

I have recently replaced points ignition with the electronic one. I have put in Pertronix 91146A Ignitor II and PerTronix 45011 Flame-Thrower II 45,000 Volt 0.6 ohm Coil. I have not bypassed the resistor wire as the instructions that I could find for that kit and engine I have did not say to do so.

First time on the water the engine ran like a dream (in comparison to the points ignition), a lot smoother and more quiet. We went around the lake for about 2 hours with no issues accelerating. After 2 hours we went into a marina to admire bigger boats :) we were traveling at pretty much idle for about 15 min, engine idling well with no issues. When leaving the marina and trying to accelerate the engine just kept bogging down. I was able to push it to about 1500-2000 rpm and after about 5 min I was able to accelerate without any issues again.

Went out 6 more times after that and it worked like a dream, again no issues what so ever.

7th time out the boat launch we used was on a shallow part of the river so I needed to go at idle for about 10 min when I got to the open water and tried to accelerate the same issue happened as before. When trying to accelerate the engine would just bog down and die. I kept pushing it slowly and I could hear what sounded like a back fire a few times, then the engine woke up and worked like a dream for the rest of the day.

8th time out went around the marina again at idle for about 10 min and same issue again when on the open lake. Eventually started going but when I stopped off at another marina to look around went back to miss behaving on the open lake. Eventually it started working but ran a lot rougher now and noisier more reminiscent of the way it ran when I had points ignition.

I really hope this makes sense to someone as it makes no sense to me.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,314
rebuild your carb and clean the fuel system

BTW, electronic ignition can not make the motor run better than properly serviced points.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,627
Several have replaced points with Pertronix and many have had trouble afterwards. Check to see if your coil is getting hot. Look at your plugs to see if their fouling out.
 

gucio1

Seaman Apprentice
Joined
Aug 17, 2020
Messages
38
Several have replaced points with Pertronix and many have had trouble afterwards. Check to see if your coil is getting hot. Look at your plugs to see if their fouling out.
Hey guys, thanks for your help. Just figured I will update this in case anyone else has a similar issue. it ended up being a defective ignition coil. I put in a new one and it is working really well.
 
Top