3.5hp Mariner carb dumping gas

I've got a 1982 Mariner 3.5 (Yamaha I'm told). It would start briefly with full choke, then die out quickly. I figured stuck float so I pulled the carb apart and hosed it out. Parts for this motor are obsolete, so it was reassembled with the old stuff. Anyway, it fired right up and ran like a champ.

I let it sit for a week and tried to start it, and it was back to dying out, so I whacked the carb bowl a couple of times with a screwdriver handle and shook the heck out it. Well, it started and ran fine, but gas was pouring out of the carb throat--not a drip but a stream. So now I'm guessing the float is stuck open.

Anyway, to get to the question part of the program:
-It's a sticky float, right?
-If Gumout didn't fix it, what will?
-Is there an equivalent carb from another model or model year that would have suitable parts for the carb?

Thanks,

Chris

Re: 3.5hp Mariner carb dumping gas

Look at the sealing surface of the needle valve. Some are metal and others are rubber. Any definite deformation of that is your enemy, i.e. any ring around the point. Other than that possibly your float isn't adjusted properly. A good rule of thumb is, with the bowl off, invert the carb and look at the float. With the carb horizontal, the float should be parallel to the surface where the bowl mates.

I'm guessing needle valves are pretty much the same size....like valve stems on tires. You might be able to get a carb kit for a newer similar hp engine and fix your seat if it is leaking. Changing the needle and seat works best.

Mark

Re: 3.5hp Mariner carb dumping gas

Thanks much.

The cartoon in my head shows the float itself not moving freely on the pivot rather than the needle not sealing well, does that make sense?

thanks,

Chris

Re: 3.5hp Mariner carb dumping gas

When the parts lists show NLA, you have to take the p/ns and go looking:

P/N 80077M

http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=200625654466+&item=200625654466

Gerry

Re: 3.5hp Mariner carb dumping gas

Look at me, livin' and learnin'...

Thanks much!

Chris

Re: 3.5hp Mariner carb dumping gas

null said:

Thanks much.

The cartoon in my head shows the float itself not moving freely on the pivot rather than the needle not sealing well, does that make sense?

thanks,

Chris

Click to expand...

Certainly! Anything that would keep the float from exerting pressure on the needle seat and sealing.

Mark