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'96 Merc 25 2 stroke help.

A

Alex from GA

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It's a manual start. Serial # 0G322xxx Come off plane and it quits. The lower plug is fouled. Change the plug and clean it out and it runs. This happens several times a day.
 
According to the book the correct plugs are NGK BP8H-N-10 and the Autolite replacement is # 4092. I used both, and yes I'm carrying several new ones with me. I even tried hotter plug. The float level isn't adjusted by the method you suggested; it's not connected to the needle. I'm setting it about 3/4". As far as slow speed use, I don't do too much if I can help it. I don't know the full throttle RPMs because of no tach; but it seems in the proper range. Top speed, by GPS, is 29 mph with a 13" prop. I just bought 4 more plugs, two NGK and two Autolites and am going to try it.
 
I found a problem today and remedied it. There are 2 small hoses from the cylinder block to below the carburetor and one was leaking. It still didn't do the job. I reset the float level to 1" and it ran worse so I put it back to 3/4" and tried it. Now it won't idle at all until I keep pressing the primer. I have another carburetor kit that I'm going to install tomorrow. My take is the fuel pump part isn't working correctly and it's running very lean. Good way to hole a piston. Can you think of anything else? Thanks.
 
It's blue. I ran it on a hose today but couldn't get it idleing. I'm taking it home where I have more tools and can test more thoroughly. It's still dying. I can restart it if I hold the throttle open. Thanks kimcrwbr1 for all the help. I'll write when I get into it again. The fishing wasn't too good anyway.
 
Alex from GA said:
It's blue. I ran it on a hose today but couldn't get it idleing. I'm taking it home where I have more tools and can test more thoroughly. It's still dying. I can restart it if I hold the throttle open. Thanks kimcrwbr1 for all the help. I'll write when I get into it again. The fishing wasn't too good anyway.
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Take a good fuel sample and look for any water/debris in it. If it looks nice and clean, you probably need carb work. If it doesn't look clean, then you'll need both new fuel and carb work.
 
What kind of carb work do you recommend? I already installed a carburetor kit after I boiled it out, washed it in hot water, blew it out and adjusted the float level.
 
Met a guy online that knows Merc 25s. Turns out he lives 25 miles from me. Took the engine there and it was fixed in a couple of hours. It has a high and low speed trigger and the low speed wasn't working. I tried many forums and finally found the right one. Johns old mercs. I had to buy a Merc 200 that needed parts to find that forum. Anyone need a perfect running 200?
 
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