1957 35HP Big Twin (hitting hard Knocking)

[nwcove]

Re: 1957 35HP Big Twin (hitting hard Knocking)

What are you using for oil? Modern oils usually mix well and do t separate from the gas.
Jmo, but i would get rid of the cork float. Ive never reused one no matter how good it looked or how light it felt.

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

OMC oil from walmart.. ok, will do on the float....

 

[itsaboattime]

Re: 1957 35HP Big Twin (hitting hard Knocking)

The block is part of the powerhead. The biggest part. It is the aluminum casting that everything goes in or bolts to. The engine itself(block, pistons, carbs, flywheel, etc..) is called the powerhead. The powerhead bolts to the leg which has the driveshaft run through it to the lower unit. The lower unit holds the gears and runs the prop.
There were LOTS of these outboards made. They are still out there. Very solid motors.

 

[HighTrim]

Re: 1957 35HP Big Twin (hitting hard Knocking)

They dont make a modern style float for the 35hp actually. The new ones you order will be the same cork style.

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

I noticed the plugs have a lot of oil on them? Will that keep it from sparking or is that normal?

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Something wrong with the choke? It has no effect on the cranking? Does this mean float stuck? reason why flooding?

 

[nwcove]

Re: 1957 35HP Big Twin (hitting hard Knocking)

They dont make a modern style float for the 35hp actually. The new ones you order will be the same cork style.

never would have thunk it!!! no modern plastic float will fit?... like with the smaller motors?

 

[kfa4303]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Hi bigballer. Lack of spark is due to a faulty ignition component. It's well worth the effort to get a $20 "tune-up" kit and replace the points and condensers. The spark plug wires themselves may also be bad, in which case you'll need to replace them with some 7mm copper core wires. Most autoparts/small engine shops sell it for a few $ a foot. Be sure you're using Champion J6C plugs as well.
As for the choke not having an effect, are you pulling it manually, or is it and electric choke? While you do need to pull the choke upon cold start, you shouldn't need to use it much beyond that and engaging it while the engine is running will usually flood the engine and cause it to stall. Make sure the lo/hi speed needles are dialed in properly as well. Here are some links that can walk you through a carb and ignition rebuild. They're for slightly different models, but all of the steps are the same.


3 HP Evinrude Lightwin Ignition System Tune-Up 1952-1967
5.5 HP Evinrude Johnson 1954-1954 Carburetor Tune-Up Procedure

 

[HighTrim]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Nope, it is a different, better type of cork material though with different coating though. The new replacements have a lighter tinge to them.

Evinrude Johnson OMC 0375792 - Float & Arm A @ MarineEngine.com

 

[nwcove]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Something wrong with the choke? It has no effect on the cranking? Does this mean float stuck? reason why flooding?

if the choke is stuck closed it will cause flooding or running very rich. but that would have nothing to do with pumping the primer ball and having fuel pour from the front of the carb .

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Pouring from carb is most likely stuck float right?

 

[nwcove]

Re: 1957 35HP Big Twin (hitting hard Knocking)

could be a piece of something stuck in the needle seat not allowing it to close when the bowl fills and the float comes up, or the float has absorbed gas and wont float, or the float is set to high and wont close the needle all the way.

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

OK, got it. Will look into issue as described. Thank you!

 

[bigballerg]

Re: 1957 35HP Big Twin (hitting hard Knocking)

UPDATE! So, i took apart the carb and noticed that the carb kit I purchased that was compatible with mine was actually not. The brass piece (arm) that holds the actual CORK was about 3mm longer than my original one. At the time of installation I didn't even check as it looked exactly the same. The float would get stuck once in a while rubbing on the edge of the bowl... Anyway, swapped the brass pieces out to my original that fits perfectly centered in the bowl. Now i have IDLE.... Boat engine running great! Until the next crisis hits.....

 

[kfa4303]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Schweeeeeeet!!!!! vroom-vroom!

 

[Willyclay]

Re: 1957 35HP Big Twin (hitting hard Knocking)

Great catch, it's usually the little stuff that gets you! FYI, the OEM carb float was made out of cork and coated with shellac. Modern ethanol-laced fuels will dissolve the shellac, saturate the float and cause it to not float anymore. Plastic foam replacement floats are available. Good luck!