71 Johnson 40 hp now this is a smoking motor any ideas on troubleshooting?

[Toolbag0125]

Hey guys I'm new to the forum I just finished fixing my 1960 tomahawk and just picked up a motor for it. I thought I would be able to handle getting it going by myself but I really need some help from someone smarter then me when it comes to outboards.
The motor is a 40el71g. I replaced the fuel filter/ pump and plugs which allowed me to get it fired up. This thing smokes like a freight train and I am not sure what to do from here. It seams like there is excess fuel at the plugs but I cannot find any adjustments on the carb. I have 2 separate manuals for this motor and none of them say anything about carb adjustment just removal and install. There are 2 knobs on the carb needles labeled slow rich/ lean and fast rich /lean. I have tried adjusting those with no apparent change in smoke.
I have read a lot of post on here and watched a few YouTube clips but the clips are not smoking any where near as much as mine is. I also read something about a thermostat but again my books do not say anything about where the stat is. I ran the motor for a while with the old plugs and when I pulled the plugs they were soaked and black which is why I changed them thinking they were not hot enough. I put the factory plugs ( had to cross reference) back in.

Below is a YouTube link so you can see what I am talking about. It is my first you tube clip so forgive me for the shaking.
Any help would be greatly appreciated.

http://youtu.be/n-95L3mWOgo

 

[racerone]

Does primer bulb go hard when you fill the carburetor with it ?-------There is no thermostat on that motor.------Hopefully you are mixing fuel at 50:1 on it.----Try putting carburetor needles all the way in gently.--Then turn the low speed jet out 1 1/2 turn and the high speed jet out 1 turn for initial start.

 

[steelespike]

Be sure the choke is opening all the way.

 

[steelespike]

When making the final idle mixture adjustment the motor needs to be warm, at about 700 rpm in gear and free to move.You are mixing
fuel at about 2.6 ozs per gallon?

 

[Toolbag0125]

Yes primer bulb is hard. I mixed exactly 6 gallons of 89 gas with 16 oz of oil and mixed it just like the book said. Adding all the oil to one gallon of gas mixing it throughly and adding 5 more gallons of 89.
Choke is open all the way. I just borrowed buddy's compression gauge and am getting about 130-135 on top and about the same on bottom give or take one or 2 psi

I will try moving the needle but I donot have anyway to see what RPMs i and running

 

[Toolbag0125]

I just went to try and adjust the needles but the appear to be all the way in. I tried to turn them some more but it's pretty tight and don't want to break it. I can turn them out no problem am I missing something?

 

[Will Bark]

Turn the needles in GENTLY till they stop; then turn each out as per Racer's post above. Don't force them tight because you will ruin the needles.

 

[nwcove]

no mention of a proper carb cleaning and rekit?

 

[Toolbag0125]

Ok the needles needles didn't not seam to help.

Nwcove you are correct I have not touched the carb yet. Reading the manual it said 9/10 times its not the carb. If you guys think that should be my next step I will do it but i didn't want to rebuild carb prematurely. I was also hesitatant because I have not been able to find the high speed needle. I have been looking for the parts if it came to that.

 

[F_R]

In the first place, it is supposed to smoke. But your main problem is you are running it in that barrel. Get it out of there and out on the lake so you can adjust it properly. You can't do that in a barrel. Once adjusted and "blown out", I think you will find it is much nicer to live with.

The carb needles Have to have some effect. You just don't even have them close. Again, get it out on the lake.

 

[Toolbag0125]

Ok so when I was messing with the needles I didn't see any difference in smoke but the motor did sound different and run rough I put the needles back and it was the same. I checked plugs and realize one was crooked. I think when I checked compression I screwed the gauge in to far and the valve hit the end of the gauge which messed up my threads. The plug is not going in. I will have to get a heli coil to fix.

In the mean time I also noticed that my slow valve is not in as far as the fast. There is a brass peice that is sticking out on the slow valve but not the fast ( as seen in pic) is this the way it's susposed to be or do I need to try and get that brass peice on the slow valve all the way in like on the fast valve?

 

[racerone]

Facts for you.-----The lower needle is the high speed and to be out for about 1 turn for start-up.---The upper needle is the slow speed mixture adjustment and out about 1 1/2 turns from seated.-----These adjustment are for start-up only after carburetor work is done.-They must be adjusted by the operator after warm up for proper operation.----The brass nuts you see are packing jam nuts and they are there to be tightened so that mixture needles do move from vibration.-The packing nuts have nothing to do with actual mixture.-----You might want to post a picture of the end of the high speed needle , as folks have been known to get these 2 needles mixed up.

 

[steelespike]

You need too unhook the linkage on the high speed; gently turn in to lightly bottomed , back it out one turn and install the linkage so it gives you room to adjust in both directions.

 

[racerone]

You need to make sure that the needles are gently seated before turning them out.---If you do not move that piece held on the end of the needle with the screw you may not be seating the needle.----It looks like the clamp on the needle might be bottoming out before the needle is actually seated !!!!!!

 

[F_R]

Those initial settings as already advised are for a place to begin. They will be too rich and need to be adjusted from there. And that has to be done on the lake. To do that, run the motor at WOT (Wide Open Throttle) and slowly turn the high speed needle to the right till it starts to falter, then turn back to the left till it regains power. Then slow down to idle and do the same thing with the slow speed needle. When you get that one too lean it will sneeze and maybe stall. Turn it back towards rich (left) till it quits sneezing & stalling. Now go through the WOT/idle procedure again to make sure you got it right. Your smoke should be much less by now, but like I said, it is supposed to smoke some. It smokes because the oil that you put in the gas is burning.......virtually all 2-strokes do that. Except a new e-tech. You can buy one for $$$$

BTW, there are no valves to contact the compression gauge (or spark plug)

 

[old islander]

Quite honestly, with a motor that old I would have started with a carb rebuild. No way of knowing it's condition without opening it up. A carb kit is under 20 bucks and then you know exactly what you are working with. Running in a barrel like that is never going to have it running right. The motor is chocking on it's own exhaust. When you do that, at the very least set up a fan to blow the exhaust AWAY from the motor while running. The needle adjustments mentioned by the guys above are only a preliminary adjustment to get the motor started and somewhat running. Grab a buddy and have him drive the boat while you sit in the back and make the final trim adjustments to the carb. I say grab a buddy because trying to do this yourself will be futile. When you hit the sweet spots with your mixture adjustments they won't be able to pry the smile off your face, but again I myself would start with a carb rebuild and VERY close inspection of the condition of those needles and their seats. A dead giveaway you need a carb kit is you have stated numerous times turning the needles is having no affect.

 

[gm280]

Obviously you do need to clean the carb and install a kit and probably a float as well. But something in your video looked weird. Or maybe it was just the angle or lighting or something . The "Smoke" actually looked like it had a lot of water vapor in it from what I seen. Yes there was the typical blue smoke, but seemed a lot of steam or water vapor in the exhaust. Maybe I'm wrong but I watched and that is what I though of... So maybe you have a water leak into the intake as well... IDK!

 

[pn]

i know you said your primer bulb stays hard but take a look at your fuel pump there may be a hole in your diaphram hole leaking gas gas gas down into your crank case.

 

[Toolbag0125]

Thank you all for the help. I am not sure what happened when I was doing a compression check but was able to get the heli coil in last night. I also pulled the low speed needle out and compared it to a picture of a new one and it is pretty jacked up. The end is slightly bent there is a grove going all the way around toward the tip and a slight indention about 1/16 from the end of the needle.
I did order a new one which should be here by the weekend. I am going to try and take her to the river this weekend and follow y'all's advice. I will let you know what happens.

 

[Medicman613]

I would just like to give my 2 cents on this issue. I have been restoring a 1957 Johnson seahorse 7.5 hp outboard and ad a similar issue. I personally don't suspect that your carb is the solution to a smoking motor. But I think you made the right move in ordering a new Jet needle. Certainly setting the screws properly will help you out a lot with your motor running smoothly at high speed and at low speed. BUT I don't think you need to get into pulling your carb completely apart.

Typically with a motor that has been sitting over time and did not have the fuel properly drained your ''jets'' (Small passage ways that run through the carb) become clogged and don't allow fuel to pass into the cylinders. Your motor seems to be starting pretty flawlessly which is good.

1. Have you looked at the actual spark that you are getting from both of your plugs? My problem was a dead plug was leading to incomplete combustion in one of the cylinders resulting in a lot of greasy/ oily build up. When I replaced the plugs and was then getting a good spark my motor was now burning off all of that incomplete combustion material resulting in LOTS of smoke for a couple of minutes running time.

2. Check your Coils under your flywheel. In a lot of older motors the plastic coils visibly crack leading to poor spark or no spark. Ensure you are getting a bright blue spark. NOT a yellow spark. This can lead to incomplete combustion and lts of smoke and a poor running motor.

3. Is your motor properly cooling? Eg. Do you have either a steady stream of water coming out of the exhaust port or is it spitting water? If your motor is not properly cooling it can lead to an overheating motor and lots of smoke. If it is not properly cooling pull your lower unit off, clean out the water pump housing which is likely clogged like mine was, Replace the impeller and the gaskets and reassemble.

I HOPE THIS HELPS!

These were all problems I encountered and now my motor is only smoking as much as any motor would.

Let me know how it goes!

Cheers,
Curtis.