1993 Mercury 115 4cyl Issue Help!!!!

nolawall

Recruit
Joined
Oct 26, 2015
Messages
4
Hello new to the group here in this forum and looking for some help. I was on a deployment for 8 months and just got back. I left my boat up the entire time. In the gas I put fuel treatment to make sure that it wouldn't go bad while I was gone. So the other day I take it out and run it. The boat ran fine for a little while. even took it out and opened her up and she got up to speed no issue sounded really good. We then go to go fishing and while we are fishing I have the motor off. When I try to start her up she sound like ass and wont start. When I put it in gear it would just die. It would pop and sputter and just sounded like something was not firing. So I take it home and remove the inline fuel filter, the water separator filter and rebuild the fuel pump. Still no change its back firing a little and will not rev. When I rev it it just bogs down. I am not sure where else to go but to the electrical side. I don't think its the carbs because it was running fine 20 min before I turned it off. So now I am thinking ignition coils. Can someone please help me with this. What test can I do to eliminate all the things it could be and fine the issue.
 

xdescrubx

Recruit
Joined
Oct 27, 2015
Messages
2
easy first step would be to check if you have spark at all the cylinders, auto parts stores sell an in-line tester, around 10$. if you have spark, smell the spark plugs after trying to run the engine. if one smells like gas, your not burning all the fuel at that cylinder. might be bad spark plugs/wires.
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Welcome aboard.

Are you still using 8+ month old gas? I would start with fresh gas.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,782
Welcome aboard.

Are you still using 8+ month old gas? I would start with fresh gas.

+1. But before you dump what you have, pour some into a container and look at it and smell it. Let it sit overnight and see if you have water at the bottom or a milky slime floating around in it which is homogenized water and additive.....that displaces water. Really don't think your spark sources would just up and go bad like you mentioned, but fuel problems, you bet. I use an automotive timing light to test for spark. On that engine, even at idle, the sensor doesn't even need to be on the plug wire...just get it close and it should light off....mine does and connects to the engine 12v power.
 
Top