Another outboard question

[Joeytier]

I picked up a nice condition 1970 viking 6 hp outboard a couple weeks ago for my 12 footer. The first time I had it out it would run quite well at speed but idled very rough with lots of sputtering. I did some research on the motor and adjusted the premix and added seafoam and lead substitute, and had it out again for a night trolling. I was impressed by how well it idled, and trolled down beautifully all night, however my top end has dropped drastically (close to 50%). I consistently noticed that if I throttled up too fast it would struggle to find gas and sputter out, but if I go slowly it will eventually find the gas, but certainly not where it should be. Any idea as to what is causing this? I am guessing it is fuel delivery issue?

[Bernie]

The Seafoam most likely loosened up some debris and it ended up in the high speed fuel circuit in the carb partially blocking fuel supply.

[Freshtrax]

i'd pull the carb and clean it out propper..

[chris.brock]

Bernie's a good guy to have around here for sure

 

let's see a picture of this beast Joey

[Sinker]

I'd taker for another good rip and see if it will blow out. Sometimes the seafoam takes a while to work things out of the system. No doubt, there is lots of crud worked out of it. If that fails, its time for a proper carb clean and set up.

 

S.

[ecmilley]

How olds the fuel line? Had a few real old ones disintegrate inside and plug up everything hows the glass bowl fuel filter look under the cover. If ok what bernie said

[Old Ironmaker]

If I had a 44 year old wall hanger and it started I would over the Moon. Neat find, super bonus she runs at all. I wonder if it's worth more to a collector. Sell it for big money and buy something newer. I wouldn't. Man it is so cool when I see an oldie but goldie pushing a 50 year old Sears car topper. Please be gentle to her. Heck she must be 80 in outboard motor years!

[Joeytier]

Fuel lines are fine(look damn near new actually), haven't checked for weak spark but I suspect thats a nonissue and that it's a high speed jet issue. Funny that I have the exact sane goddamn problem on my big bear now. It's a shame that I hate tinkering with old motors, or else I might be having a little bit of fun with this...

[Big Cliff]

Once it "finds it's fuel" as you put it, does it seem to be ok on the top end (other than slower). I am just wondering if when you adjusted the low speed you leaned it a bit too much. I would try turning the low speed jet back out about 1/8 of a turn and see if that improves it.

[Joeytier]

I haven't had the carb apart at all.

[Freshtrax]

Clean the carb out proper, or risk burning it down. No fuel and two stoke = melted pistons.