Sputters, but won't start - not sure what to do

[Gas Giant]

Engine is a '61 Evinrude Lark III, 40hp, Model #35524

Long story short, the entire ignition system has been replaced. (points, condensers, coils, spark plug wires, spark plugs). Points were gapped to 0.020". Spark was verified with an automotive spark tester set to 7/16".

All of the engine's other wiring has been replaced.

The entire fuel system has been replaced, except for the fuel pump. (All new fuel lines and filter). Fuel pump was disassembled and cleaned out, and the diaphragm appeared to be in good condition with no holes or tears.

The carburetor was torn completely down, welch plugs and all, and soaked in a bucket of carb cleaner. When I took it out of the bucket I blew out all the passages with a can of carb cleaner. It was then rebuilt using an OMC carb kit P/N 439074.

However, I can only get the engine to sputter when I try to start it. I am using the pull starter as the electric starter still needs a solenoid, and after a few hours of tinkering and pulling, I am pretty darn tired. I tried it in the Choke On position, the Choke Off position, and the Automatic position (even though the automatic position is essentially the same as the On position when starting). The longest it ran was about 3 seconds, but for those glorious 3 seconds, it seemed smooth.

So, I'm not sure what to check first. It seems like a fuel delivery problem, but I'm open to ideas. The place I got my spark plugs didn't have Champions, so I have AC Delco in there for now - I doubt that could cause this problem, could it?

Anyway, any ideas as to what I should check or try next are appreciated. I'm not sure what to do at this point, and my arms feel like rubber.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Just ran a compression check - I got 70 psi on one cylinder and 72 on the other. Certainly not spectacular numbers, but they are very similar......is this too low for it to run with the lower submerged?

I did notice that the plugs were wet from cranking when I pulled them out.

 

[lindy46]

Re: Sputters, but won't start - not sure what to do

70 and 72 by hand-pulling is a little low, but not unreasonable. If you can get her to fire, try pumping the fuel line bulb and see if she stays running. May be the fuel pump. I wouldn't even try to pull-start a 40hp motor - especially if it hasn't been run in years. Sometimes it just takes a lot of cranking to get them to eventually turn over and keep running. I'll bet if you get the starter working, you'll get her running.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

I don't think I CAN try pull starting it anymore.......I can barely move!

What you said makes sense, because most of the time it wouldn't sputter until the 3rd or 4th pull, and by then I was running out of wind. (yea, I need to spend more time on the treadmill......)

The starter problem is a strange one, because every now and then it turns the motor over nice and strong...but such instances are rare, and it usually baaaaaarely moves it......one slow pulse at a time. I'll do some more investigating on this circuit and report back.

 

[kfa4303]

Re: Sputters, but won't start - not sure what to do

Sounds like you've done everything right up to this point Gas Giant, so I'm inclined to agree with lindy46's suggestion to get the (a) starter working, or call a buddy and get him to pull it for you My 20 hp isn't the easiest thing in the world to pull start, so I can't imagine what and old 40 hp is like. I would also run Champion J6C or J8C spark plugs rather than the AC Delco ones you currently have, just to be safe. These old OMC's were designed with Champion plugs in mind and there can sometimes be tricky trying to find equivalencies in other brands. Are you using copper core s'plug wires, or graphite automotive ones by accident? You may also want to try putting some fuel/oil mix in a spray bottle and squirting some into each cylinder prior to start up. That may help "prime the pump" so to speak, and help get it started. Then, you can also it to spray mix into the carb while the motor is running. If the motor picks up when you spray in your mix then you have a fuel delivery issue. From what I've heard, the old starters aren't too difficult to rebuild, if need be. You might even be able to get on e off of a donor motor, for cheap, if you're lucky. Keep us posted.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

All good suggestions. The spark plug wires are copper core wires; I got them from a local marine supplier. The shame of it was I had enough Accel spark plug wire left over from car projects to do this outboard, but I couldn't use it!

I did try spraying pre-mix down the carb throat before some pull starts - when I did that, it would usually sputter right away, instead of waiting 3-4 pulls to start sputtering. I didn't try shooting it directly down a spark plug hole.

I'll look more closely into the starter and see what I come up with. Its gonna be a day or two before I can pull that hand starter again...

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Two slight updates:

I experimented with the starter today - I hooked it directly up to the battery for a moment. Even without the solenoid, it could barely turn the engine. So I am going to pull it apart and see what I can find inside the starter.

And, I think I may have made a mistake rebuilding the carb. In the bowl, there is a high speed jet. Well, I never took it out. I can't actually get it to come out. However, carb cleaner does spray through it.....so I doubt this plays into my problem? Its not going to be easy to remove...

 

[kfa4303]

Re: Sputters, but won't start - not sure what to do

Hi Giant. The hi speed needles should screw out. Take your time and try not to strip or bend it in any way. A pit of PB plaster may help free it up too. The hi speed needle setting is important for hi end performance (obviously) and for start up, sthat may be why you're having trouble getting and keeping her going. It doesn't take much goop to keep a carb from working properly. These links may help some.

http://www.duckworksmagazine.com/06/columns/max/index10.htm
http://www.outboard-boat-motor-repa...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm
http://forums.iboats.com/showthread.php?t=16735

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Well, I think I made a mistake in my last post - the high speed nozzle is the one that is in the center of the carb, according to the parts breakdown I saw online - I DID get that part out and was able to clean it out - the part I couldn't get out is referred to as an "orifice plug" and is in the bottom of the float chamber behind a screw.

 

[AlTn]

Re: Sputters, but won't start - not sure what to do

the orfice plug is the high speed jet...all fuel flows through it....do a search and you'll find the dimensions for a jet removal tool or part no. 317002 < looks like a thin shanked screwdriver with a head that fits the jet precisely >...if you have to try to clean it in place, twist some copper wire together so that it's smaller in diameter than the jet opening and gently twist it in as you would a drill bit while alternating with carb spray. < you don't want to distort or enlarge the jet orfice >..this jet and the area behind it need to be spotless for the carb to work properly

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Great! Thanks for the info, the differences in terminology between my manual and the parts breakdown confused me.

The machinist at work made me a tool to get the jet out. For now, I took the float bowl off and I put a small lake of PB blaster in the bowl, filling the area where the jet resides from both sides....going to let it soak for a day or two before attempting to remove it.

Also pulled the starter apart, but I am going to have to read more about what it says in the manual before I go asking questions on the forum.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Got the orifice plug out. It was clear, but I cleaned it and the passage it was in really well with carb cleaner and compressed air. Didn't see any particles or anything in the passage or the plug when I shone a flashlight down them.

Got it back together, and gave it a few pulls - same story, sputter but no run. But this isn't an accurate test; I think I may have actually hurt myself last Saturday because the few pulls today really hurt my shoulder. So I am going to have to fix the starter, however I can't seem to find anything wrong with it based on the manual other than that the commutator is a little dirty. Well, that and I don't have a growler.....

 

[AlTn]

Re: Sputters, but won't start - not sure what to do

not familiar with that carb....does it have 2 needles to adjust or just 1, which would be for the low speed mixture?...finally looked at a 1961 not 1968 and found the model no. you listed <bad eyes>...did you install part no. 307778..float chamber to carb body boss gasket?...idle mixture needle is set at how many turns out?.....float was parallel to carb body when the carb was inverted?

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

This carb has one adjustable needle, for the idle/low speed. That needle is kind of frustrating me, as I am not entirely familiar with them. The manual I have says to:

"Start the low-speed needle valve packing nut into the opening. DO NOT tighten the nut at this time. Thread the low speed needle valve into the low-speed opening. Continue threading until it barely seats. After the needle valve seats, back it out 1 1/2 turns counterclockwise. Now tighten the packing nut until there is drag on the needle valve, but the valve may still be rotated by hand, but with a little difficulty."

The part that is giving me a little trouble is that where it "seats" seems to vary quite a bit based on how much you threaded the packing nut in before starting the needle valve.

What I did was thread the packing nut in a few turns, and then followed the directions from the manual. Hopefully that's the right way to do it. However, I did try threading the needle valve out more, or in more, when attempting to start it on Saturday...nothing seemed to have an effect on the no-start condition.

The high-speed jet is in the fuel bowl and is a fixed orifice that I took out and cleaned yesterday.

I'm going to try and get the starter back together - I couldn't find anything obviously wrong with it, other than being a little dirty inside. I don't think I can hand crank this thing for awhile.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

AlTn: You must have edited your post as I was writing mine!

To answer your questions:

1) Yes, I replaced that gasket. The old one was not recognizable as a gasket anymore!

2) Idle screw was set at 1 1/2 turns out, per the manual. Attempted a few other settings as well. See above post for some frustration regarding this thing

3) Float was parallel to carb body when inverted.

 

[lindy46]

Re: Sputters, but won't start - not sure what to do

There is a threaded bushing/sleeve that the needle screws into which could be turning in the opening. Make sure the packing nut is pretty tight, as that is what keeps the bushing from spinning. If it's not tight, it's impossible to adjust the needle.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

I think I have that part sorted out now....thanks!

As for the starter, cleaned up the commutator and got it back in. Unfortunately, the battery I was testing with was low - I could have sworn I checked for that, but maybe I am mixing that up with another project I'm working on. Tried it with a different, unknown-condition battery, and it seems to spin a little faster....not fast enough to start the engine, but faster than the other battery....so I have the original battery on the charger now and I'll check it out tomorrow.

 

[AlTn]

Re: Sputters, but won't start - not sure what to do

as Lindy stated in post #3....once everthing gets wet again, it'll probably start....once the starter is straightened out things should go better

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

I think I'm throwing in the towel.

I put a fresh battery with a full charge on it today, and again it barely cranked the motor. To make sure I didn't have a bad battery, I used a multi-meter while cranking and the battery voltage didn't drop below 10V while cranking. All the wiring in the boat is new: battery cables, key switch wiring, everything.

After a few attempts, I touched the starter case, and it was blazing hot.

I can't afford a starter at this point, heck I can't even afford to have it rebuilt. So I guess I'm done with this boat for the near future. Thanks for the help, and sorry this one had to end in failure.

 

[Gas Giant]

Re: Sputters, but won't start - not sure what to do

Here's an update for those that responded:

I was in a better mood today, and the weather was favorable, so I tried it again. This time, I used the battery out of my Bel Air, which I know is a good battery. The starter did it's usual sometimes-work-sometimes-not game, but.....

I set the throttle to fast-idle, gave it a healthy dose of pre-mix down the carb, and hit the key. By chance, the starter decided to cooperate, and flung the flywheel around like never before, and low and behold - the engine fired up!

It only ran for about 10 seconds, but it ran! Subsequent attempts with the starter didn't work, but it would fire right up with the pull start without the need for additional pre-mix or causing me bodily harm. So, you guys were right, it just needed to be convinced to wake up with a lot of cranking.

So, it runs, but its far from water ready. It runs rough, but I assume some tuning will clear that up. What concerned me was the brown, muddy-ish stuff floating on the top of the water in my water barrel I was running it in. I don't think it came from the lower unit; I changed the oil in that before I tried starting the engine.

But, those are questions for another topic - I just wanted to say thanks to Altn, lindy46, and kfa4343 for helping me get this thing going, even if it isn't running right yet.