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6902m 6hp fisherman no spark

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daveman927

New member
I just picked up a 69 6hp Evinrude fisherman and I need some help.

the plug wires are generating voltage to the plug however the plug is not sparking. I purchased new plugs and confirmed they were grounded to the motor when testing.

I pulled the flywheel and everything looks good on the magneto. I did clean everything up to make sure it wasn't a contact issue.

Is it possible its not delivering enough voltage to create spark on the plug?
Is there a way to test what's actually making it through the plug wire?
 
That magneto in good condition can generate up to 28,000 volts.----Make sure points are clean and set properly.-----Make sure coils are not burned through and grounding to the magneto plate.-----Replace condensers.----Replace plug wires.-----Those magnetos were installed from 1950 to 1990 and very good , simple and reliable.
 
Great little motors. You should take all of Racers advice as well as view spark with a simple spark gap tester. Spark should be able to jump about 1/4 to even 5/16 inch and then you know you have a good magneto. Condensers rarely fail but points can get pitted and if there is any sign of pitting on the points they should be replaced. Some replacement coils are not as good as others and I have seen where the hard plastic, most commonly in a mint green color, will crack again and sometimes arc down through a small hole into the stator plate, shorting out your spark. Be sure to set your coils at the back edge of the chamfer at the top of the mounting posts. This will provide adequate clearance between your coil face and the flywheel magnets. When you install the points make sure they are property aligned and put just a tiny bit of high quality grease on the stem where the points pivot. If the small wick which holds the oil is deteriorated or missing you don't have to worry but put a little bit of that high quality grease, I use Amsoil synthetic, on the cam follower. If you must change the wires make sure you use a very high quality copper core which are flexible and soft. Make sure they are pushed completely into the coils and clamped down securely under the stator plate. Gap points at .020, take your time and get it accurate. After all this you probably won't have to do anything for about another 20 years. Just go fishin'. You might want to consider replacing the head gasket as well, especially if it hasn't been replaced yet. The replacement gaskets are an improvement over the original units which tended to burn across between the two cylinders causing low compression.
 
Ensure the spark plug gap is correct, and check the kill switch, ignition coil, condenser, points, and timing. Confirm the ignition switch is functional.
 
There is no ignition switch on a 69 model.-----There was no kill switch installed when new.-----That magneto was used for many years.----Should be an easy fix.-----There are many u-tube videos to guide you. some better than others.
 
Thanks everyone for the insight. I went a head and changed everything on the magneto plate. Coils, Condensers, points (checked gap), timing, plug wires, & plugs (checked gap). I was able to get it running briefly and only with the throttle wide open. I cleaned the carb and replaced the float, needle and gaskets. The problem I'm having now is the carb intake floods out but only while running so now I'm getting too much fuel.

Thanks,
 
Edchris177 said:
If the carb floods out, check the float needle & seat. Replace them as a matched set.
Click to expand...
A new needle and seat came with the carb kit. I'll open it back up and reinspect everything again.

I was looking at a diagram of the carb and was wondering if someone could shed some light on this lead shot. Where is it on the carb and what is it for?
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It’s from the manufacting process. The lead shot is to seal small passageways drilled during manufacturing. There was a thread here yesterday about that exact bit.
Is your float set at the correct level? With the float bowl upside down, the float should be level.
You can test the needle valve before installing carb. Put a piece of tube on the fuel inlet. With carb right side up, you should be able to gently blow through- the needle is open allowing fuel in). Turn it upside down, you shouldn’t be able to blow any air in- the needle is closed, blocking fuel in.
 
Edchris177 said:
It’s from the manufacting process. The lead shot is to seal small passageways drilled during manufacturing. There was a thread here yesterday about that exact bit.
Is your float set at the correct level? With the float bowl upside down, the float should be level.
You can test the needle valve before installing carb. Put a piece of tube on the fuel inlet. With carb right side up, you should be able to gently blow through- the needle is open allowing fuel in). Turn it upside down, you shouldn’t be able to blow any air in- the needle is closed, blocking fuel in.
Click to expand...
Thanks for the clarification on the lead shot.

When I pull the carb I will do this exact test.

Now something I just noticed. I went outside and pulled the plugs just to check. The top cylinder is firing and the bottom isn't so I'm going to rerun the plug wire for the bottom plug. Is it possible that the motor could briefly run on a single cylinder and then eventually flood itself out?

The carb is only flooding when its running. Once the motor stops so does the fuel so maybe its flooding because both cylinders aren't firing...
 
Very common for those to only run on one cylinder.-----And the design allows them to run on 1 cylinder all day long !----And the flooding has nothing to do with a cylinder not firing.-----Also check / replace the fuel pump diaphragm.-----Easy and cheap to do that little pump.
 
racerone said:
Very common for those to only run on one cylinder.-----And the design allows them to run on 1 cylinder all day long !----And the flooding has nothing to do with a cylinder not firing.-----Also check / replace the fuel pump diaphragm.-----Easy and cheap to do that little pump.
Click to expand...
thanks for confirming. I bought a new fuel pump for it. I missed that one in my list of items I replaced.

Thanks,
 
I would never buy a new fuel pump.----Certainly not an Amazon " special " .----A new factory diaphragm would fix it for many more years of super reliable operation.------These motors are elegantly simple / reliable / cheap and easy to maintain.----Check the thermostat as they are often stuck open.----Installed a new impeller ?
 
I kept the original fuel pump so I'll look into some diaphragms for it. I did get an Amazon special fuel pump. I haven't checked the thermostat but I'll check and see if its stuck open. I did replace the impeller on the water pump.
 
You can test the thermostat easily. Put it in a pot with a couple inches of water on the stove. Borrow your wife’s meat thermometer. T Stat should start to open at 140-145F. It should be fully open as water goes over 145F ish.
Turn the heat off, slowly add some tap water, T Stat should close as soon as water temp decreases.
Before you open up that fuel pump, look up Leroy’s Ramblings, & maybe a couple other good You-tube rebuilds. Leroy’s has an entire section on the 6hp, & a dedicated fuel pump rebuild.
Then start by throwing your Amazon parts in the trash, I’ve never read of anyone having good service with those diaphragms.
 
I'll try and check on the thermostat tomorrow if i have time. I have new plug wires coming in tomorrow.

I did pull the carb off this afternoon and confirm the float was set correctly per the service manual. The needle valve sat correctly. With the needle completely seated, I couldn't blow compressed air at 30psi into the carb. when I flipped the carb over and the needle was open I could blow air in. I reinstalled the carb and as I pulled on the starter, the intake barrel started to have fuel flow out of it.

I don't understand why I cant get it to crank on start setting but can get it to temporarily start at wide open throttle.

Like earlier just going to throw something out there. Is it possible the Amazon fuel pump is forcing fuel into the carb?
Is it possible for the fuel pump to overcome the float in the carb?

Is it possible that even with 95psi of compression that there could be some air leak on the intake side not pulling air into the motor directly through the carb that would also carry fuel?
 
I wouldn’t ever subject the float valve to 30psi. The pump will not overpower that valve, check your service manual,they only put out about 1psi at idle.
Are you starting it with the throttle cracked? The markings on the twist throttle may be way off. Owners manual states that throttle closed kills motor.
Is the throttle cam set correctly? There is a mark on it, it should just start to open the butterfly when the cam follower, (#16) is at that mark.
i currently have a ‘69 on the stand. It had been “worked on” & had the wrong cam, even at hard idle the follower was pressing on it.
 
The fuel pump runs with CRANKCASE pressure pulses.-----Not the same as the compression in the cylinder.-----Lot of guess work being done here in my opinion !
 
Edchris177 said:
I wouldn’t ever subject the float valve to 30psi. The pump will not overpower that valve, check your service manual,they only put out about 1psi at idle.
Are you starting it with the throttle cracked? The markings on the twist throttle may be way off. Owners manual states that throttle closed kills motor.
Is the throttle cam set correctly? There is a mark on it, it should just start to open the butterfly when the cam follower, (#16) is at that mark.
i currently have a ‘69 on the stand. It had been “worked on” & had the wrong cam, even at hard idle the follower was pressing on it.
Click to expand...
With the handle set on start it moves the throttle probably a 1/4". If I move the handle to shift then its completely off the throttle meaning the butterfly would be 100% closed so I might need to adjust that. I did purchase the service manual so I will go through that section and see if I can get it set properly.

Thanks,
 
racerone said:
The fuel pump runs with CRANKCASE pressure pulses.-----Not the same as the compression in the cylinder.-----Lot of guess work being done here in my opinion !
Click to expand...
You would be correct on the guess work. In all honesty I don't know anything about outboard motors. I am mechanically inclined don't get me wrong there but I just have never worked on outboard motors or really any small motors.... With that being said I'm defiantly not a master mechanic but when it comes to vehicle motors I'm much more knowledgeable. I do feel like I can get this motor running I just don't think I can do it without yall's help. Folks here know a lot more about this then I do and I really appreciate the help.

Any advice any of you can give me I will defiantly look into and reference the service manual for extra guidance.

again thanks everyone for the directions. I picked the outboard up for $200 and its close to running.
 
daveman927 said:
Is it possible that even with 95psi of compression that there could be some air leak on the intake side not pulling air into the motor directly through the carb that would also carry fuel?
Click to expand...
The 2-stroke intake is a different cat than 4-stroke. In your motor, every bit of air/fuel goes through the carb & into the crankcase. As the piston cycles, the crankcase sees positive & negative pressure pulses, that’s what powers the fuel pump, & moves mixture into the cylinder.
The butterfly stays closed during the first portion of throttle twist. Adjust if it is not as described above..
 
One thing we may check here is to ensure that that the little donut gasket is making its seal at the base of the float bowl. Sometimes they are not thick enough to properly make a seal, or the tabs on the float bowl get slightly bent and the float does not pull itself as tightly as it should to the aforementioned donut. If this seal is allowed to leak fuel, then you have unmetered fuel dumping into the carburetor, but only when it's running or if you are trying to start it. This can be checked by removing the float bowl and quickly looking at the donut to see if there are marks from where the stem has squeezed it.
On another note I worked on an outboard motor similar to yours where a fellow put an Amazon fuel pump on and it still would not get fuel. So upon removal of the fuel pump I found that the output stem had not been drilled out yet. Ha, pretty crazy, so I just drilled out the stem and everything was fine.
 
Thanks everyone for the advise. Last night I spent a good deal of time going back through everything as well as putting new plug wires on. I will be checking out the thermostat very shortly.

I was able to get it to run for a good 5min and I was able to get it to idle as well until it died however I am able to get it to fire back up pretty quickly so that's very encouraging.

Something I noticed as it ran/idled that I didn't see happening in videos I watched is the armature plate where the cam throttle control is mounted appears to move side to side.

I wish I could upload a video to show what I'm seeing but the throttle cam and the plate is moving left to right as the motor runs instead of staying perfectly still and only moving as I twist the handle.

Other then that the only thing I've noticed is there is a slight oily substance coming out the exhaust as well as what appears to be carbon. As I have gotten it to run more it has become less.
 
The oil out the exhaust is normal.---A worn out bushing on the magneto plate may be the reason for the wobble.-----Folks rarely grease that bearing.----And at 4000 RPM the vibration / shaking causes wear.
 
so just to provide an update.

I checked the thermostat and it was stuck open so I just ordered another one.
I put a new water pump on but noticed it wasn't pumping water like it should. Pulled the lower unit off and realized I missed the water tube so I got that fixed.

I finally found a good video on the idle control knob..... I'm basically missing the tip so I think thats my idle issue. I also learned how to properly install that piece with the washers so now its more air tight.

Currently it runs great. I can get it to crank and run. It doesn't like to idle but that should be fixed when I get the new needle.

Seeing how this thing has sat for a couple years, you think its a good idea to run seafoam through the gas?


Thanks everyone for the advice and direction on getting this far.
 
If the tip was missing / broken on the slow speed needle you have to look into that.----Might be stuck in the carburetor.----Need to remove that broken piece.-----I can not see / touch your carburetor , i am just going by little bits of information posted.
 
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