I just bought a 1982 (I think) 25 hp Seahorse, that the seller told me idled fine but wouldn't rev out on the water. Carb, fuel pump and lines are done. Tank appears like new and the bulb pumps up hard. Plugs are new.
Sure enough; when I fired it up in a barrel I could get it to run and idle, but when I put it in gear it would bog down, sputter and stall.
I tore the carb down thinking the high speed was clogged, but everything was spotless. Put it back together and got the same result. Scratched my head a bit and unplugged first the top plug wire then the bottom. The top wire stopped it dead, the bottom made no difference at all. I switched the plugs and then the wires with no change what-so-ever. It took awhile but I eventually found my compression tester and spark tester. Compression is fine, and there is no spark on the bottom with the tester at 1/2 inch or so.
Here's the weird thing, that I discovered mostly by accident. Although it will run with the bottom wire off, it won't start with the same wire off. That has me baffled, but its perfectly repeatable.
What do I do or try next?
Sure enough; when I fired it up in a barrel I could get it to run and idle, but when I put it in gear it would bog down, sputter and stall.
I tore the carb down thinking the high speed was clogged, but everything was spotless. Put it back together and got the same result. Scratched my head a bit and unplugged first the top plug wire then the bottom. The top wire stopped it dead, the bottom made no difference at all. I switched the plugs and then the wires with no change what-so-ever. It took awhile but I eventually found my compression tester and spark tester. Compression is fine, and there is no spark on the bottom with the tester at 1/2 inch or so.
Here's the weird thing, that I discovered mostly by accident. Although it will run with the bottom wire off, it won't start with the same wire off. That has me baffled, but its perfectly repeatable.
What do I do or try next?
