Yamaha 3SF anyone? Not an antique but I thought I would ask

[bullie]

Has anyone worked on a Yamaha 3SF? I have been staring at this thing for 30 min and cannot figure out how to remove the carb. Someone left it for a long time with gas in the carb. It smells pretty skunky but would probably run if I could just figure out how to take off the carb.

[retiredoz]

Looks like it’s held on by two thru-bolts. Here’s a sketch :

http://www.marineengine.com/parts/yamah … 0304230002

[billw]

Yeah, #44 holds it on, bolted right through. I have to admit that I like the way they do that. Yamaha orifices are small, so be meticulous with it.

Long live American manufacturing!

[bullie]

Yeah, I see the bolts. The problem is that they are up against the lower cowl. I was hoping there was some secret to it that didn’t involve disassembling a lot of stuff.

[retiredoz]

‘Design for assembly’ strikes again ! Sometimes all you can do is determine the assembly sequence and work your way backwards..

[billw]

It would be very unlike Yamaha to make a carb that you can’t get off. (Somebody would have to fall on their sword for THAT one.) Remember that all you have to do is back off the bolts enough to clear the threads, then lift to whole thing up and out with the bolts still lose in the carb.

Long live American manufacturing!

[bullie]

Thanks for the help guys. Usually if something is hard to do, you are doing it wrong. LOL I was doing it wrong. I finally saw a seam and realized the front of the lower cowl is a separate piece. From that point it was just figuring out which fasteners I needed to remove. A very nasty carb with completely blocked jets and some kinda gunk growing in it was the issue. Started right up after a cleaning. And even ran pretty good after a second cleaning. LOL The hole in low speed jet is slightly smaller than tiny. Another learning experience. Thanks again.

[bullie]

This is a shot of the carb from above with the starter rope bracket removed. You can see the bolt on the right clearly. It can be loosened easily enough. Possibly it could be loosened enough to back out of the block, I didn’t check. As you can see the air silencer is nearly touching the lower cowl so there is no access to the left side bolt from above or the side. The lower cowl is 2 pieces held by clips and bolts at the top (above the shifter and tiller arm) and bolts underneath. When those are removed there is easy access to the carb bolts for removal or any other necessary maintenance.

Thought I would add a picture and a brief explanation in case someone searched this motor or issue as there is very little information about it out there on the world wide interweb. Might help someone out down the road.

[Author]

Posts