Evinrude Speeditwin 6039 Starting Help

[gearhead4]

So after one nasty blister from the pull chord, 4 days tinkering/thinking/trying to start my 1939 6039 Speeditwin, I’m looking for a refresher/any tricks I should look into. This engine, when I ran it last, was easy to start and I agree with other posts that once dialed in, they run awesome! That was when I had a "Club" foot on it which has been updated to the later fishing lower unit that I’d really like to test out with a speed prop.

What I’ve done so far:

– Followed starting instructions to the "T" (Gary had an old post I found in the forum)
– Pulled carb twice and nothing stands out, everything is clean and clear
– New carb base gasket (I cut it from material since the original was leaking slightly)
– Checked the mag, she’s hot and points are freshly cleaned which produces a nice spark (Newer Champion D9’s which I have not swapped to test a separate set of plugs)
– Fuel flow is good and getting into engine from carb
– Compression is superb, my right arm is definitely stronger after the past week of playing with this thing

When attempting to start, the most I’ve gotten is about 3-4 sputters before it cuts out. Most of the time it would backfire which means lean so I’d open the low speed in small increments to adjust this but still it just doesn’t want to catch. Also to note, this is all being attempted dry hanging on the transom of my boat, if I can’t start it in the driveway easily then why bother at the ramp! Sorry for the Merriam Webster post, takes a lot of words to hopefully make it understandable. Any thoughts/suggestions or a run through of how you run yours would be appreciated. I may just be rusty since it has sat for several years, properly put away and drained but I’m eager to get her back out on the lake. Thanks in advance.

[Tom]

Sputtering a few times has been, to me, and indication that a condenser is going or gone. One or two sparks at hand cranking speed is an indication of coil condition, not condenser health. Exact symptoms wore me out on a Johnson last month. You have a two cylinder motor with only one condenser. That sounds like a time saving opportunity!

When you start with the needle valve closed, and open it in increments, do you run the carb dry first? If the float is hanging up, or the seat is leaking, the carb will flood. Try it with the tank valve off.

Best of luck!

Tom

[ftruntz]

Make sure the primer is working. Also that the tubing connecting the primer to the cylinder is clean. My experience with ny 6039 is if the primer dosen’t work you will have great difficulty starting the motor.

Regards;
Fred

[gearhead4]

Thanks for the responses. Tom, how do you go about testing a condenser? I’ve searched and tried a couple things but not 100% sure if I’ve got it correct. I’m definitely leaning towards ignition being the issue with this engine. Checked spark late last night in the dark and found only occasionally did I get a good snap across the plugs, it wasn’t every revolution. I have OMC condensers from modern stuff I could throw in but wanted to know what’d work. OMC part #: 580321 is what I have, I got over-shipped when I ordered 1 several years ago so there’s a few spares in my parts bin. I’ll start with a condenser test then go from there. Since we’re on the topic, I believe you’ve measured the coils before, anything I can do to "Check" the one I have out with a Fluke meter?

Your carb questions: The needles move smoothly and the float needle valve stem does move cleanly with the bowl cover installed, had to align it a certain way but it does not hang up.

Tom, it may be worth catching up in person sometime since you’re close by. I started a new job so I’m no longer flying down 95 daily but we aren’t far apart.

Fred, the primer works well and pushes plenty of fuel into the crankcase so that’s okay. I’ve rechecked the fuel system again last night and ruled it out, there’s no issues I can find other than the needle packing gland being loose. That’ll get resolved later, more important is to get the old girl to fire up.

Looking forward to hearing back with some advice.

[Tom]

Gearhead,

(Is this Matt?) We can test all the condensers and coils you have. Call me at 509 three three nine, 3546 after 7:00.

A little background here… The condenser needs to store energy, then release it when the points open. Think of it like a gas can with an inlet and an outlet. The can has a certain size. The inlets and outlets can restrict flow if they are too small. And the can may leak. OK, hold that thought…

There are a few parameters that are important for use in a magneto. One is how much energy to store. That’s the capacitance (like the size of our gas can). Anything from 0.1 to 0.3 uF will probably get the motor going.

Another parameter is how quickly it can store or release the energy (the size of the inlet and outlet fittings on our gas tank). I think that’s the dv/dt value. Typical electronic capacitors have dv/dt values that are too low for our purposes, but special ones can be found with the right numbers. There is one you can get from DigiKey that works fine, the number is somewhere on this board.

The last value that affects use in magnetos is how quickly the energy will dissipate if the condenser isn’t hooked up to anything, the leakage rate (yep, our gas can may leak). Many meters measure leakage rate. The best ones measure it at a pretty high voltage. The homemade one with the neon light, or the one in the Merc-O-Tronic and Stevens testers, test at or near 120 volts. My Stevens tester has been a very good predictor of whether a condenser will work in a magneto. The Heathkit condenser testers, like the old C-2 and C-3 models, can test at higher voltages. I’ve found that a condenser known to be iffy will fail at 250 volts, but might appear OK at 150. So I like to test them at the higher voltage.

The stand up WICO condensers, with the screw terminal on top that were used in Scotts and Martins, are notorious for being bad. I’ve tested new ones and they failed. Every used one I’ve tested showed some leakage. Best thing to do with them is cut out the bottom, remove the guts, and put in one of the recommended capacitors from DigiKey. It’s a little bit of work, but retains the binding post on top that will keep wires and the strap from the points from getting caught by the flywheel.

I recently tested an original condenser from a ’30’s Caille, and it was fine. Well, there you go.

Testing coils is pretty straightforward. First you measure the resistance across the secondary. If it’s an open circuit, the coil may actually work by sparking across an internal gap. But that coil is doomed, as it will eventually burn away material and stop working. Then you measure the current required to throw a spark. If it’s too high, there’s something wrong with the coil. It may work, but probably not for long. There are charts available that tell us the recommended current each coil needs to work.

Hope this helps.

Tom

[gearhead4]

Thanks for the info Tom, yes this is Matt. Let’s catch up later. Finally getting caught up with projects at home – long story – which have taken the majority of my summer away. Are you going to be at the ISPE show at Gillette next week? Contemplating on going, probably will. I have several mags we could look over and you could show me how you test them. I have never really had to go into a mag too deeply other than wiring but I’d like to learn it. Rather have "Hot" reworked mags than find one fail a mile down river from the ramp. This Speeditwin and the Giant Twin mags are the first ones I’d like to review since those are my ongoing projects I’m trying to complete, Speeditwin’s much closer to running though than the Giant but that’s happening soon.

Lets catch up later.

Matt

[The Boat House]

If you find that the ignition isn’t the problem
check the primer check valve at the cylinder
that it is closing. (dirt – spring has failed)
An open valve can cause you all kinds of
starting and running problems.

[Randy in Tampa]

ditto on priming the motor if it doesn’t prime it won’t start also try some NGK AB6 or AB7spark plugs mine doesn’t like the champion D9s 😉

quote FTruntz:

Make sure the primer is working. Also that the tubing connecting the primer to the cylinder is clean. My experience with ny 6039 is if the primer dosen’t work you will have great difficulty starting the motor.

Regards;
Fred

[fmanracer]

Speeditwins love fuel. My experience with them is to hit the primer about 10 times. The other thing is there is no need to adjust the low speed valve unless you have a running motor and are trying to get it to idle. When you are pulling the motor over with your rope it’s the high speed needle that needs to be adjusted. I’d say open the high speed needle 1 turn and open the low speed needle 1 turn also. Push the primer 10 times and start pulling. After pulling 8 times with no results assume its flooded and shut off the high speed needle. continue pulling. After 8 to 10 more pulls you should add enough oxygen to lean it out enough to start.
When it starts don’t forget to quickly open the high speed needle to keep it running. Adjust the high speed needle for maximum response. Throttle the engine back to idle and close the idle needle 1 click at a time until it coughs and dies. It went lean while idling and died. Open the idle a couple clicks and restart the engine. Bring it to idle again and see how it dies. If the engine runs really slow and does not cough and die it’s either just right or slightly rich. Most folks get them to cough and die then richen them up a couple clicks and idle fine. The only time to adjust idle is with the engine idling.
You should also do all this mixture set up on a boat while staying close to help or a dock. My advise is to get it to start in your driveway if you want, kill it then get the prop in water. It is very possible to over rev an outboard with no load on the prop.

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