1959 omc big twin 35 runs bad.

42 Clyde

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Im restoring a 1959 omc big twin 35 Sea king electric start, electric choke. I got the motor back togeather after doing rings and every gasket i could get my hands on. New coils points condensers plugs Carb kit New fuel lines. Upper and lower crank seals. New fuel tank primer bulb and fuel lines. I went thrugh the timing and syncronization of the carb several times. You name it i took it apart, cleaned it or replaced it. It runs like garbage and i dont know why. What am i missing? Please help.
 

F_R

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Have no idea. Describe garbage, what is it doing/not doing?
 

racerone

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Need to adjust the carburetor I think.----Is this the first motor you have worked on ???
 

42 Clyde

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This is not the first motor i have worked on. This is the first outboard i have rebuild.
The motor takes alot of cranking evin when choked to get it runing. When its idling it runs and sounds good some times. Anything above idle it wants to gerk around but its not a miss. When i get it in the water it it vibrates the whole boat and doesent rev up. Only once for about 15 seconds dit it start to rev up and smooth out. But it never gets to full speed.
 

42 Clyde

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Ignition coils are brand new from the dealer. Not ebay! I have heard bad stories about ebay parts. Having the hood on or off does not help. Having the intake mufler on or off does not help either. As far as the coils.... what are the primary and secondary ohm readings suposed to be? I will check them just in case. How would the hood afect the motor running?
 

F_R

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Resistance varies with manufacturer. General rule of thumb is around an Ohm for the primary, and a few k-Ohms for the secondary. They range all over the place, 4-7 k-Ohms,

Famous "head scratcher" is people leave out the seals on top of the water pump, which causes hood to fill up with exhaust smoke, which means the motor breathes it's own exhaust smoke. We all learned that the hard way, back in "The Day".
 

42 Clyde

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Primary is 1.1 ohm on both. Secondary is 4.7K ohm on both. Dont mean to pry but.... How far back was “The Day”?
 

racerone

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Does spark jump a gap of 5/16" , yes or no.-------There are folks on here who could overhaul that motor from top to bottom without a single glance at a manual.------Motor was still " new " when some here started working on them.----Say 50+ years ago.
 

F_R

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Your coils are ok.
I started in 1954 as an after-school job. On my first day, my boss reached under the work bench and dragged out a box containing a completely dis-assembled old Briggs & Stratton engine and told me to put it back together----and I did, never having seen one before. Those were the days.
 

42 Clyde

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Yes the spark will jump the gap. I tested it with a see-through spark tester under compressed air.
I however could not overhaul this motor without reading the manual from cover to cover. If i pull either spark plug wire while its running it will compleatly change the tone of the motor. But both are Equally dedrimental.
 

42 Clyde

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So if the coils are ok. Is there something in the timing or the carb i need to look at?
 
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