Tohatsu M25C - Won't Start?

[Ober51]

I am hoping you can provide me some advice. I know next to nothing about outboards, this is my first controlled motor. Please excuse my terminology while I try and explain.

After I spent the last two days building a stick steering setup I tried to start the motor for the first time today with no success. I followed everything the PO did (connected the fuel line, primed the ball, pulled the choke) and tried to start it with the key rather than pull start like he did. It fired up for about a second and then nothing. I had the choke out and turned the key again, and it fired up for a second and then died, it sounded like it choked out. After that the motor never engaged, only the starter (I think that's what it's called) engaged and worked. It sounded and looked like it was trying to start every time, it just wouldn't start. Like a car trying to start but won't turn over. I then disconnected the controls, and tried without them like we did at the PO's house, and use the manual/pull start, and it wouldn't start up. I don't know what to do seeing as I have never really owned a motor before. Not compression, since it was tested at 130psi each cylinder. Maybe fuel? He said the gasket in the fuel filter needed to be replaced but was fine as is (leaks minimally). I did notice some dripping from what looked to be the area above the choke inside the cowling. It was like a steady drip almost.

I tried two batteries, and the motor sounded like it was trying to start, it just wouldn't engage.

Someone suggested it could be the kill switch ground but I did push the kill switch in to make sure it was connected, so I don't know if it's that. There is one wire that is not connected to anything that comes out of the harness (or whatever it's called that houses the turn key). Could that be it? The guy didn't use the electric start when he demo'd, he just connected the wires under the cowl and the pull started it, took 2 pulls and it was running really, really strong.

Please help! I am trying to avoid bringing it to a marine mechanic!

 

[pvanv]

Re: Tohatsu M25C - Won't Start?

Ober,

Not to be negative (we all have to start at these things somewhere), but it sounds like you don't have the basic skills to diagnose fuel issues. Dripping fuel near the carb (or elsewhere for that matter) is never OK. Not even at the filter/settling bowl.

If you can get a friend to help -- one who understands these things, then you will probably be OK. Otherwise, you will either need to learn that stuff yourself, or you will want the assistance of a good outboard mechanic.

I would suggest that you have probably over-choked the motor, and/or flooded the carb with excess fuel due to an internal problem. I note this because it seems from your description that all of your cranking was done with the choke closed, and that you had fuel dripping from near the choke. Once the plugs are wet with fuel, they will definitely not fire until you take them out and dry them, or replace them. In addition, if there is a fuel drip near the carb, there is likely either a fuel line leak, or the carb is over-filling. If it is over-filling, that's a sign that you need to disassemble and clean the carb to get the float, needle and seat working right.

A Factory service manual (available at any Tohatsu/Nissan dealer) can help a lot with the fuel system. I would check on that dripping fuel filter/settling bowl as well as the carb. Once you have those things working, you are on the way to getting the rest working properly.

Since the motor started on the second pull during the pre-sale test, I'd suggest that your issues are minor, but you will definitely need a hand from someone who has a solid foundation in these principles. Also, since the motor started -- at least for a second or two -- with the electric starter (definitely nice to save your pulling arm), the remote setup is probably OK. In order to know the purpose of that spare wire coming from the key switch, it would be good to know what color it is. Some of the RC units have optional wiring, so a spare wire is not necessarily a problem.

 

[Ober51]

Re: Tohatsu M25C - Won't Start?

I realize I dont have many of the skills, so I will likely have to bring it to someone that has them. I think you are right, it makes sense, that I may have over choked the motor. I have the factory manual, so I will start there again. But I will likely have to bite the bullet and bring it to someone like you who has a clue. Thanks a lot for this information, I realize its probably annoying to have to listen or read about this stuff all the time from people who haven't a clue.

 

[Ober51]

Re: Tohatsu M25C - Won't Start?

I woke up today telling myself it was something stupid I was overlooking, something minor.

Well wouldn't you know it, it was something stupid, something minor! I simply had to move the fast idle level on the controls into the up position. It worked on the first turn after I did that. Pumped water great, etc. I am pumped to get the stick steering out there tomorrow. It feels like it should work well. Thanks again for giving me a bit of insight!

 

[pvanv]

Re: Tohatsu M25C - Won't Start?

I realize I dont have many of the skills, so I will likely have to bring it to someone that has them. I think you are right, it makes sense, that I may have over choked the motor. I have the factory manual, so I will start there again. But I will likely have to bite the bullet and bring it to someone like you who has a clue. Thanks a lot for this information, I realize its probably annoying to have to listen or read about this stuff all the time from people who haven't a clue.

We all have to start somewhere, so please don't apologize. I'm glad you figured it out. Yes, it appears that you were supplying too much fuel and insufficient air, a form of over-choking.

Still, review any fuel leaks, and get them remedied -- it will pay off in safety and convenience down the road.