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9.9 1974 Johnson Heavy Black On Plug

patiolatern said:
Thanks!
I will be back on this motor in a couple hours.
I do the blow test on the inlet every time I take it apart and I do have the retainer clip on the inlet valve connected to the float but will double check if/when I take it apart.
Does anyone have the specifications on float position for this motor? It’s a pretty shallow bowl.

I will double check the fuel tank venting as well as the other ideas you had.
Click to expand...
Ok here is the result of todays activities:
Raised the fuel tank to about 12” above motor and started the motor. Started pretty good. Warm it up and give it some throttle and it did the same thing EXCEPT it sort of saved itself from stalling. Wasn’t pretty and I may have squeezed the bulb but nowhere as much. Brought engine down to slower speed where it would run smoother. I then elevated the fuel tank about 2’ above motor and made sure there was no sag in hose. The motor again bogged down but then caught up and continued to run. I did not have to use the bulb(maybe once). I had to lower the speed since it was running a little to fast in the barrel.
I do not see or hear any air leaks on fuel lines.
I did vent the tank and there were no changes to the issues.
I did disconnect the fuel line running from pump to carb and pulled the rope/starter. Very little fuel came out. I did this a few time pulling 10x on the rope with same results no fuel or very little fuel.
Squeezing the primer and fuel flows out of pump very well.
Checked the mesh screen and it seems clean and fuel flows from it easily.

Going to take carb off to maybe change that welsh plug I missed and to triple check the inlet valve and the float setting.
What about the height of the float at low fuel this carb seems shallow?

Thinking I probably need a fuel kit?
Any recommendations besides OEM? Do I just buy the kit or the housing too?
Thanks!
 
Have you tried a completely different fuel tank?
Yup, we all started out just like you. Only difference is we had to go to our mentor at the Johnson/Evinrude shop for advice and instruction. My mentor was a Bill Swanson at Bay View Boat works. My big mistake was not buying his shop and home, right on L. Superior's St. Louis Bay. He left it to a stupid idiot nephew that destroyed the wonderful business because he wasn't capable. Bill was another "Racer" or "Joe Reeves". He would instruct and let me help when I was in my teens. Fell in love with outboard motors.
 
Seems you may need some direct help. Did you look behind the fuel pump? If the diaphragm is bad, that will cause low fuel pressure, low volume and mimick your symptoms. You will have fuel in the "pulse port" behind the pump.
 
timguy said:
Have you tried a completely different fuel tank?
Yup, we all started out just like you. Only difference is we had to go to our mentor at the Johnson/Evinrude shop for advice and instruction. My mentor was a Bill Swanson at Bay View Boat works. My big mistake was not buying his shop and home, right on L. Superior's St. Louis Bay. He left it to a stupid idiot nephew that destroyed the wonderful business because he wasn't capable. Bill was another "Racer" or "Joe Reeves". He would instruct and let me help when I was in my teens. Fell in love with outboard motors.
Click to expand...
I have tried another fuel tank as well. My main motor ran on both of these tanks with both fuel lines with no issues
 
Low temperatures in combustion chamber means that plugs go black.----Look into that fact or keep cleaning the carburetor a few more times.
 
It does sound like you have a malfunctioning fuel pump. I would think a fuel pump rebuild kit would probably do the job. Perhaps others have some thoughts.
 
optsyeagle said:
If you decide to rebuild your fuel pump this link can be quite helpful. It's easy to get a confused with all the parts and how they are oriented and of course, there is only one right way to do it and as always, many wrong ways. Good luck.

Click to expand...
Great instructions and yes I am ordering the fuel pump kit. I love the idea of a fixture which I may use.
FYI:
I did take the carb apart and changed out the welsh plug. No issues were found but I sprayed the areas and blew them out.
Float looked to be in the right position and functioned correctly when held upright and upside down
I tried to remove the Center jet(high speed) but it would not budge and I didn’t want to damage it. I believe the same thing happened when I first rebuilt this carb.
Other than that it was clean as usual.

Reassembled and motor has same issue(no surprise)
I consider a fuel pump kit a consumable and am ordering it but the old one does not look rough or old. It will be interesting to see what happens in a couple days once the kit arrives.

In the meantime I will be able to give my arm a rest. The motor is on my boat so starting it with my left arm is awkward and I am getting old. Lol

Thanks again for all the help and support and let’s keep our fingers crossed!!
 
Note to Racer. Post #9 covers the operating temperatures. If you keep taking apart the carburator, it can not be doing it any good....
 
....perhaps Racer is in a sarcastic mood. This repair has gone on way too long. If that motor was in my hands it should have been running great in a couple hours max. Have you looked in the pump pulse hole for gasoline? Have you checked for carbon deposits in the exhaust chamber? Has the high speed jet been cleaned to its correct size. Is the fuel pump providing enough fuel volume? Is there any vacuum leaks about the powerhead? Are you providing ample fresh air? Is fuel/oil mixture right at 50:1? Are the spark plug wires in good condition....no abrasions or damage that could arc out? Are kill button wires free from abrasions? If its been running rich, how are the motor mounts? How Is the ground wire from powerhead to cowling? How are the reed valves? Was there ever a mouse nest in there?
 
timguy said:
....perhaps Racer is in a sarcastic mood. This repair has gone on way too long. If that motor was in my hands it should have been running great in a couple hours max. Have you looked in the pump pulse hole for gasoline? Have you checked for carbon deposits in the exhaust chamber? Has the high speed jet been cleaned to its correct size. Is the fuel pump providing enough fuel volume? Is there any vacuum leaks about the powerhead? Are you providing ample fresh air? Is fuel/oil mixture right at 50:1? Are the spark plug wires in good condition....no abrasions or damage that could arc out? Are kill button wires free from abrasions? If its been running rich, how are the motor mounts? How Is the ground wire from powerhead to cowling? How are the reed valves? Was there ever a mouse nest in there?
Click to expand...
Well thanks for the feedback. I think optsyeagle has been doing very well guiding a rookie on outboards.
Is it taking to long? I don’t think so.
To many posts? I don’t think so.
Is it hard to communicate via a forum on everything. I think so.

We tried not to throw parts at this and figure it out. The issues go back to me being inexperienced on outboards and communicating via a forum for assistance.

Let’s wait and see once the fuel pump kit comes in and go from there.

Thanks again for everyone’s help!

FYI. I do not see much if any fuel in the pulse port. Again this is coming from zero experience examining a pulse port and any issue related to it.
 
I think I know why some posters tend to focus on the number of posts but we all need to keep in mind that the number of posts is a function of how many other posters decide to chime in, the usefulness of those posts, and whether the thread starter is courteous enough to respond to all those posters, whether their input was helpful to him or not. Also if the thread starter is interested in the theories behind why we suggest some of these tests or just wants to be pointed in some direction as quickly as possible.

As patiolantern has stated it is difficult to parlay precise information about problems and symptoms and test results on internet forums, as well as parlaying useful suggestions with the reasons they are suggested, and hence that tends to expand the number of posts as well.

I suspect if a poster had the same knowledge as some of the people on these boards they most likely would not be posting at all and this board would get pretty quiet, pretty quickly...and we need to remember that none of us were born knowing how to fix an outboard. It is an acquired skill.
 
The fuel pump is powered by crankcase PRESSURE pulses on the diaphragm.------If diaphragm has a hole it would flood one cylinder with way too much fuel.-----Fuel would leak out of pulse port ON THE PUMP when bulb on hose is squeezed.
 
Plus, he has done a cylinder drop test a few times and both cylinders are operational. I would think if one cylinder was being flooded with gas it would have a hard time keeping the motor running when the other cylinder was shut down during that test.
 
??----post #72 says he has zero experience on examining a pulse port or any issues relating to it !----Orderly trouble shooting on this motor will find the issues !!
 
optsyeagle said:
Plus, he has done a cylinder drop test a few times and both cylinders are operational. I would think if one cylinder was being flooded with gas it would have a hard time keeping the motor running when the other cylinder was shut down during of the outside wall
Click to expand...
Post 9 and 12 talk about cylinder temps along with water jacket and spark plug temps.
The confusion was caused by me scanning the cylinder walls and getting inconsistent results to what my hand felt on the bottom cylinder wall. Both cylinders felt the same temperature which I would say is hot. You can touch for a few seconds so I think the 145 degree is accurate
 
patiolatern said:
Well thanks for the feedback. I think optsyeagle has been doing very well guiding a rookie on outboards.
Is it taking to long? I don’t think so.
To many posts? I don’t think so.
Is it hard to communicate via a forum on everything. I think so.

We tried not to throw parts at this and figure it out. The issues go back to me being inexperienced on outboards and communicating via a forum for assistance.

Let’s wait and see once the fuel pump kit comes in and go from there.

Thanks again for everyone’s help!

FYI. I do not see much if any fuel in the pulse port. Again this is coming from zero experience examining a pulse port and any issue related to it.
Click to expand...
Ok kit came in and I rebuilt the pump. Blow tested it and it seemed fine. Installed it on motor and before connecting to carb I cranked the motor about 10x and fuel was flowing to carb.
Started the motor and it idled very low then put it into gear and ran at higher rpm. It did not run well. Did about the same as before where it would bog down only it never came back or caught up with the rpm’s just stayed in the poor running state. As I reduced throttle it ends up stalling. Engine smoked a lot and very hard to restart.
Top plug was wet and bottom plug was carbon black covered. Cleaned and reversed plugs and ran motor.
Top plug was covered and bottom was wet.
Tried the old plugs but ran out of time to get it started.
Late tomorrow I may have access to a computer that can read the exact output to the spark plug so this may show something.
Thanks
 
If I recall, before you rebuilt the fuel pump, you were not getting much of anything pumping when you cranked the motor with the fuel line to the carb disconnected, so I have to assume that problem has been resolved with the rebuild.

Since your motor is acting the same way it did before we now can assume that pumping fuel was not the problem or not the only problem. That said, if I recall when you squeezed the primer bulb before I thought the problem went away for 30 more seconds etc. Correct me if I am wrong. Did you attempt to squeeze the primer bulb this time around to see if it had any affect on the bogging, stalling etc.?

The bogging down and eventually stalling would either be from gas not getting to the cylinders OR one cylinder failing (the bog) and then the other cylinder failing (the stall). The latter event being very perplexing since you usually lose only one cylinder or you lose two, but at the same time. The other question I have here is you say that the motor bogs down and then stalls. You then say you clean up the plugs, switch the cylinders they are in and then it all happens again. This tells me that the motor bogged down and stalled, but seems to start back up again. Does this re-starting only happen when you clean up the spark plugs or can you get it to re-start without doing anything? Do you need to prime it to restart it?

As for the state and color of the spark plugs. Either it is an observation telling us nothing or it is telling us that there is a problem with the spark plugs because the "carbon black" and the "all wet" happened to the same spark plug regardless of what cylinder it was in.
 
optsyeagle said:
If I recall, before you rebuilt the fuel pump, you were not getting much of anything pumping when you cranked the motor with the fuel line to the carb disconnected, so I have to assume that problem has been resolved with the rebuild.

Since your motor is acting the same way it did before we now can assume that pumping fuel was not the problem or not the only problem. That said, if I recall when you squeezed the primer bulb before I thought the problem went away for 30 more seconds etc. Correct me if I am wrong. Did you attempt to squeeze the primer bulb this time around to see if it had any affect on the bogging, stalling etc.?

The bogging down and eventually stalling would either be from gas not getting to the cylinders OR one cylinder failing (the bog) and then the other cylinder failing (the stall). The latter event being very perplexing since you usually lose only one cylinder or you lose two, but at the same time. The other question I have here is you say that the motor bogs down and then stalls. You then say you clean up the plugs, switch the cylinders they are in and then it all happens again. This tells me that the motor bogged down and stalled, but seems to start back up again. Does this re-starting only happen when you clean up the spark plugs or can you get it to re-start without doing anything? Do you need to prime it to restart it?

As for the state and color of the spark plugs. Either it is an observation telling us nothing or it is telling us that there is a problem with the spark plugs because the "carbon black" and the "all wet" happened to the same spark plug regardless of what cylinder it was in.
Click to expand...
Most times I can start it up again after fouling but not this time and even after cleaning it as hard to start. It may be flooded.
I am used to normal fouling of plugs so the reason I mention it is because it is more like a powder coating of black carbon so unusual to me.
 
Next time you are out in it and it starts to bog down squeeze the primer bulb and let us know what happens. Also, don't change out the plugs immediately but attempt to get it started again and if you do, do a cylinder drop test again and give us the results.
 
optsyeagle said:
Next time you are out in it and it starts to bog down squeeze the primer bulb and let us know what happens. Also, don't change out the plugs immediately but attempt to get it started again and if you do, do a cylinder drop test again and give us the results.
Click to expand...
Ok long day pulling on this thing.
Primed it choked it and pulled it pushed choke back in and pulled 3x. Started but stalled out almost immediately. Got it stated again and before it could stall I put it into gear and raised the speed. It continued to run poorly and just stayed in a bogged state with rpm’s not improving. Stalled out and primer bulb would not save it.
Started again after primer choke pull no choke and pulled about 5x put into gear right away and it ran for a bit then stalled. No saving with primer bulb. The motor would not start again for the balance of the day.
During the above we ran an induction coil on each plug wire to see if we could find any issues. Both top and bottom wires should consistent results with a repeating pattern. We did this also with the drill running the engine and same results. We also checked spark from each plug when grounded to engine as well as with a test light and everything looked strong.
We were going to do the drop test after the induction coil test but motor would not cooperate.

Nothing we did could get the engine started.
I don’t remember if I checked the fuel pump to see if fuel flowed while cranking the engine with the drill. I took off the fuel pump and there was a little fuel on the gasket and pulse port. A few drops. I disassembled the pump and inspected. Everything looked normal but when I put it back together the blow test would not work. Specifically I could not force my breath into the fuel inlet. I must have taken this apart 5x and even then it was very hard to force my breath in. Gave this a try on the motor and had flow into the pump but could not get flow out to carb while running the drill on flywheel
I want to say there was one point where I was able to get flow out and I tried to pull start but it did not start.
Plugs were dry at this point.
The instructions on videos, booklet with pump kit and Leroy’s ramblings all show the process of what I followed……a number of times
Is there anything in the base of the fuel pump that goes up agains the the pulse port that can fail?

On another note looking at some old pictures of my carburetor I see where I missed putting an orfice onto the bottom of high speed jet. I put the orfice back on and at this point I thought I had some air going into the pump (doing blow test)so I assembled it to motor and gave it a try to start.
It would not.

I will go over the pump assembly again and see if there was anything I am missing.
I will also start checking coils individually.

Thanks for reading!
 

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