Hi. This is a continuation of a thread I started in Aug 2010, but with a few more twists and turns. I really need help on this one.
First of all, I need to confirm the year of my motor, which I bought new in 1980, I believe.
The info on the ID plate is Mariner 15M, Model # 684 CS 010512, Made in Japan for: Mariner International Co. From my research I think it is a 1980 but parts suppliers can only come up with 1979 model.
Now to my problem. The engine starts great and runs great at idle and low speeds but I have no top end. Mechanic last year did compression tests, adjusted timing etc. Still no better.
I have checked compression myself and both cylinders are 115 - 120 PSI.
I have replaced diaphragms in fuel pump. Disassembled and cleaned carb. Still no better.
Now with new mechanic. Engine exhaust was badly carboned up so he cleaned that up. Checked compression, spark, timing etc. Still no better. Next visit to mechanic, he cleaned and reset points, timing etc. Still no better. Mechanic has engine again and is trying to determine if maybe coils are not providing correct resistance but he is trying to find out what the resistance for the coils is supposed to be.
My mechanic believes it to be an electrical problem and is pursuing this. My thoughts, and I'm not a mechanic but have some basic knowledge, is that it is a carburation problem. Why I think this way is that the plugs always seem very wet to me. I spend ninety-nine percent of the time trolling around fishing. The engine will troll for hours but then sometimes seems to shut down to only one cylinder operation. On checking plugs at this point they are soaked. Changing plugs and restarting engine is a fix for a while.
I'm tearing my hair out over this and could use some help.
Thanks
First of all, I need to confirm the year of my motor, which I bought new in 1980, I believe.
The info on the ID plate is Mariner 15M, Model # 684 CS 010512, Made in Japan for: Mariner International Co. From my research I think it is a 1980 but parts suppliers can only come up with 1979 model.
Now to my problem. The engine starts great and runs great at idle and low speeds but I have no top end. Mechanic last year did compression tests, adjusted timing etc. Still no better.
I have checked compression myself and both cylinders are 115 - 120 PSI.
I have replaced diaphragms in fuel pump. Disassembled and cleaned carb. Still no better.
Now with new mechanic. Engine exhaust was badly carboned up so he cleaned that up. Checked compression, spark, timing etc. Still no better. Next visit to mechanic, he cleaned and reset points, timing etc. Still no better. Mechanic has engine again and is trying to determine if maybe coils are not providing correct resistance but he is trying to find out what the resistance for the coils is supposed to be.
My mechanic believes it to be an electrical problem and is pursuing this. My thoughts, and I'm not a mechanic but have some basic knowledge, is that it is a carburation problem. Why I think this way is that the plugs always seem very wet to me. I spend ninety-nine percent of the time trolling around fishing. The engine will troll for hours but then sometimes seems to shut down to only one cylinder operation. On checking plugs at this point they are soaked. Changing plugs and restarting engine is a fix for a while.
I'm tearing my hair out over this and could use some help.
Thanks