1963 Viking Engine Sputtering at Idle Speeds

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1963Viking

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I have recently purchased a 1963 Viking Inboard/Outboard, model number 25DE21V. When I first purchased the boat, it ran fine at idle speeds when trolling. After I filled the tank, I have found that the boat is sputtering at idle speeds, and even shutting off on me. I noticed that the fuel line had broken, and have since repaired it-but the problem remains. If anyone has some clues as to where to look next, I would appreciate it.

Here are some of the things I have noticed/done:

-I have mixed the oil and gas to a 40:1 mixture

-To start the engine (this also started to happen around the same time), I now have to pull the choke out full, attempt to start it (never starts), push the choke back in, then it starts. Originally I only had to try the key once or twice.

If anyone has any suggestions or advice, please let me know.

Thanks.
 

samo_ott

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Re: 1963 Viking Engine Sputtering at Idle Speeds

Isn't that model a outboard 25? As I have the '62 model I believe.

It sure sounds like a carb issue. Has it been cleaned recently? Does high speed work ok? Is the problem only at low speed? You can try the cheap easy fix and take out the upper low speed needle and spray carb cleaner in there and maybe it will help. Then screw it all the way back in lightly seated and back it out 1.5 turns. Be careful when you remove the needle to not mess up the packing nuts (small cork type O rings on it)
 

F_R

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Re: 1963 Viking Engine Sputtering at Idle Speeds

Don't go running off fixing something until you at least do some troubleshooting. I assume the compression is OK, since it sort of started/ran/runs Next is the spark. It must jump a 1/4" open air gap with ease. Jumping a plug gap laying against the block doesn't count.

Fuel pump: remove it from the motor, lines connected, and squeeze the squeezer bulb. If it shoots gas out the backside of the pump, it is shot.

OK, the carb. It may be dirty or need repair. But that's the last item on my list.

You wouldn't be the guy that collects Vikings would you? Is this a test?
 

1963Viking

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Re: 1963 Viking Engine Sputtering at Idle Speeds

I am not the guy collecting Viking engines...I bought my first boat for fishing, and found a 1963 (outboard 25 electric start) viking outboard under a johnson (painted on) shell. I actually have the parts manual for the motor-the guy I had bought it from still had it with the boat.

The boat runs fine at high speeds. When I purchased the boat, I was told that the engine had been rebuilt-I have taken the top off, and there are many new, shiny parts in there. This problem started when I filled the tank-could be coincidence. The first few times I took the boat out, it started with ease. Now it seems I have to play a game with the engine to coax it to start.

The plugs are brand new-there is not a single spec of dirt on them...I had time to check this weekend.

I believe the fuel pump is new-I will double check tonight.

I am going to start by replacing the repaired fuel line, then I will check the fuel pump. If those don't work, I will see about using a carb cleaner...THANKS for the help-I am a novice when it comes to motors, so a starting point is GREATLY appreciated.

Dave
 
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tashasdaddy

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Re: 1963 Viking Engine Sputtering at Idle Speeds

spray carb cleaner will do nothing. it sounds to me like the new fuel, and broken old deposits loose, and clogging something, fuel pump, or carb low speeds.
 

F_R

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Re: 1963 Viking Engine Sputtering at Idle Speeds

OK, you threw me off with your "handle". Fuel pumps won't keep a motor from starting. You could take the pump clear off the motor and it would still start if there is gas in the float bowl.

Did I mention gas in the float bowl? Take the high speed needle conpletely out and see if gas runs out. If it does, put the needle back in and open it about 5/8-3/4 turn from lightly seated. But if there is no gas in there, you probably have a stuck float valve.

Then move on to the ignition. It wouldn't surprise me a bit if you find bad coils or a sheared flywheel key. But that guy may have replaced the coils. That doesn't mean he reinstalled the flywheel correctly.
 

JeffNilson

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Hi Everyone, I just purchased the same motor and not sure if you guys can figure out what it is missing based on below attached photos. Anyone can help please. It seems it is electric start as the boat has OMC thing to change gear and speed. Many thanks. Jeff
 

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F_R

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This is a 2008 thread. The mods will close it as soon as they discover the hijacking. Please start a new one.
 
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