1957 Evinrude Big Twin 35, Carb crazy.

exodave

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I've taken the carb apart 3 times already and keep cleaning it. Yesterday it ran wonderfully. Today the engine is kicking, stalling, seems to be overheating, and now fuel is just rampantly pouring out of this top right hole next to the low speed needle. Shall i just clean it again, or is something else going on?

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It on earmuffs. I bought the outboard 2 weeks ago and have yet to be able to put it in the water. So far, rebuilt LU with new bearings, seal kit, water pump. New coils, whole ignition kit, new plugs, carb kit.
 

Daviet

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

If gas is coming out of that hole, the float must be stuck holding the needle open, not shutting the fuel off. Pull the carb apart and inspect.
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

Yeah, I had forgotten to put back the plastic washer under the float needle valve, making it too high to close... and I'm guessing I shouldn't have put that cellulose washer around the base of the jet? It seemed like the only place it would fit, and the kit came with no isntructions, but I do not see a washe/ring there in the diagram in my manual... so i guess I'll just go by that. One more try running it tonight...
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

So, back to the same problems I keep having with this motor: It takes some fooling with the choke for a couple minutes to start. Then, after some warming up, I can put it into gear and rev it. After about 30 seconds or so, it shakes a couple times and dies, little or no sputter, almost as if someone pulled the choke. And it's very difficult to get it to idle.
 

Daviet

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

Have you checked the spark? It almost sounds like you are dropping a cylinder or plugs are bad.
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

I replaced the plugs, coils, points, condensers, and adjusted according to the manual, and checked for voltage to the plugs. I had to buy two different brand of plugs, and one is shorter, but they are both supposed to replace the originals. I guess it's worth popping the flywheel again and checking everything. I also have not checked the compression yet.
 

Daviet

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

Do you have a spark checker, you can get them at most auto parts stores. No need to remove the flywheel again if the spark is good.
What type of plugs are you running, they should be the same lenth.
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

I can probably pick up a checker. The old plugs were Champion J-8C and don't look too terribly bad actually. Of the new ones, one is a Champion J-8C and one is a Master Mechanics MM1, says suitable for J-8C. I guess I could switch back to the old plugs and see what happens?
 

Daviet

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

I would put the correct plugs in and see how it runs.
 

lindy46

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

Use Champion J4C or J6C. J8C is probably a little too hot. Also check that your pressure tank is pressurizing and feeding gas ok. How is compression?
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

I'll see if I can find a gauge to check compression, and buy some 4 or 6Cs after I put the old plugs back for the hell of it. Then, this little girl needs to get her butt in gear and get me out to some perch.
 

tx1961whaler

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

If those are original fuel lines, they may need changing. Sounds like junk is breaking off of the inside and re-clogging the carb. One of the joys of ethanol fuel is that it is an extremely good fuel system cleaner and it will break down old lines.
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

going to harbor freight for the tools today, and will pick up a good pair of plugs.

Quick question while I'm thinking about it: when I installed the new ignition (one of the coils had literally fallen apart), I was confused about two things. First, how to be sure the wire is correctly seated in the coil. Second, the kit came with two capsules of red stuff and had no idea what to do with it.

I'll take some pics and video today while I'm working on it, and try to post as I go.
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

I'll start a new thread with the video, and because I think we're over the carb problem and on to something else with at this point.
 

lindy46

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

going to harbor freight for the tools today, and will pick up a good pair of plugs.

Quick question while I'm thinking about it: when I installed the new ignition (one of the coils had literally fallen apart), I was confused about two things. First, how to be sure the wire is correctly seated in the coil. Second, the kit came with two capsules of red stuff and had no idea what to do with it.

I'll take some pics and video today while I'm working on it, and try to post as I go.

Plug wires sort of screw into the pins on the coils - just push them in as far as they will go. Capsules are cyanide to be taken if you get completely frustrated working on the motor:D No, actually they are grease for the cam. There should be a pad-like piece of felt that rides on the cam to lubricate it. Put a little grease on the felt. New kits usually come with a pre-greased felt pad.
 

Chinewalker

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

And yes, the thick round washer DOES go at the base of the main jet in the carb bowl... It has to be there for the carb to work properly...
 

rjezuit

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

Where's the packing nut for the idle top (low speed) needle? Rick
 

exodave

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

they were mysteriously missing when I took it (unknowingly until I got a manual) so I put some brass compression fittings in while the new packing nuts ship from Seattle.
 

rjezuit

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Re: 1957 Evinrude Big Twin 35, Carb crazy.

You will suck air and lean out without a tight seal on the high and low speed needles. Rick
 
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