louisvillefisherman
Cadet
- Joined
- Oct 13, 2012
- Messages
- 29
Hello. I recently acquired a 1988 Johnson 9.9 short shaft. I knew when I purchased it that it had an issue staying running.
I tested the motor on the sellers boat. It would start fine, but only run for about 30 seconds, and then would die, unless the primer bulb was pumped and the choke had to be all the way out the whole time.
I immediately suspected the fuel pump. Having to squeeze the bulb was what clued me into that, so I took a gamble and bought the motor. It looks great, clean and other than the staying running part (I know, pretty important part) I thought it was a safe gamble and am willing to do the work to get her running right.
It has been unseasonably cold here in N.E. Ohio so I did not get a chance to run the motor again for a few weeks.
When I finally got the chance, I found that I was unable to start it without first squirting some 50:1 into the breather even though I primed the ball till hard. When it did start, it was the same deal as before. Run for very brief time, die unless pressure is put on the bulb. Choke must remain pulled all the way out the whole time. Push it in and the motor dies instantly. (I have motor in barrel for testing)
The gas tank is good. Hoses/connectors are brand new. (old metal tank, been cleaned and inspected and new gasket around gauge so I am confident about everything "off motor")
Ok..so I decided to start with the fuel pump and the hoses. Replaced the longer hose from the tank line connector to the fuel pump, and replaced the smaller line from the pump to the carb. Also replaced the pump itself with a new pump.
I did test the original pump by pulling the fuel hose from the carb and gave the rope a small pull. Gas squirted right out so it was pumping, but I thought perhaps when connected it was unable to push it all the way into the carb. I was still praying for it to be just a simple fuel pump issue. One of the easiest repairs, so like I said, I replaced it.
That did not help at all. Same problem. When I was at the marine shop I picked up a can of Sea Foam carb spray and a can of Sea Foam fuel additive. I used the spray by squirting it into the air intake (after I removed breather). (did not use additive so far) Turns out I am able to keep the motor running, albeit very rough and with crazy smoke, by spraying the Sea Foam cleaner into the throat. I did not do this a whole lot because I did not want to risk damage due to possible lack of lube in cylinders. I then let the motor stall, sprayed more cleaner, let sit, ran through, no help.
Now I have taken the carb off and am waiting for a rebuild kit to arrive. I got the one with a float included.
QUESTION: Does the 1988 originally come with a cork float? The one that has been in this carb is black and does not appear to be cork like the ones I have seen on older models. I am wondering if this carb has been redone before.
The carb that I have is the plastic top and plastic bowl. In the bottom of the bowl there was a slight film of sludge, nothing I would consider gritty. There are some darker colored areas here and there (shall I call it varnish?) inside the body but not bad.
The float needle seat was probably the most colored. Varnish all around it. The needle had some color to it as well. I am hoping this was the problem. The needle perhaps getting stuck in its seat once the float pushes it in and preventing fuel from entering. I dunno, wishful thinking I guess.
I am soaking the body now for 24 hours in carb cleaner. I am also looking for some diagrams so that I can locate each of the holes that I need to clean. I read that a thin piece of wire works well. I do not have an air compressor but I am considering getting a small can of compressed air (the kind you would clean a computer with) to blow in the holes.
I will post back with the results of the carb rebuild once it I am done (parts are due Friday or Monday if eBay seller fills the order as descibed).
My main concerns at this point:
Obviously worried that this wont fix the issue and that it is a greater problem, worst case scenario I have read is that a leaking "lower crank seal?" may not be allowing a vacuum to pull fuel into system.
Also read something about bad piston skirts creating a lack of fuel. I don't mind rebuilding a carb (kinda fun) but not sure about pistons and cranks. That makes me a little nervous.
You know...they say when you are sick, never look up the symptoms on the internet because by the time you are done reading you will have convinced yourself you only have 3 days to live. I am trying my best not to do that with this motor.
But just in case, tell my family I love them. (ok...now the post just got a little creepy!)
I appreciate anyone who would like to chime in.
Thanks for reading,
Chris - LouisvilleFisherman
I tested the motor on the sellers boat. It would start fine, but only run for about 30 seconds, and then would die, unless the primer bulb was pumped and the choke had to be all the way out the whole time.
I immediately suspected the fuel pump. Having to squeeze the bulb was what clued me into that, so I took a gamble and bought the motor. It looks great, clean and other than the staying running part (I know, pretty important part) I thought it was a safe gamble and am willing to do the work to get her running right.
It has been unseasonably cold here in N.E. Ohio so I did not get a chance to run the motor again for a few weeks.
When I finally got the chance, I found that I was unable to start it without first squirting some 50:1 into the breather even though I primed the ball till hard. When it did start, it was the same deal as before. Run for very brief time, die unless pressure is put on the bulb. Choke must remain pulled all the way out the whole time. Push it in and the motor dies instantly. (I have motor in barrel for testing)
The gas tank is good. Hoses/connectors are brand new. (old metal tank, been cleaned and inspected and new gasket around gauge so I am confident about everything "off motor")
Ok..so I decided to start with the fuel pump and the hoses. Replaced the longer hose from the tank line connector to the fuel pump, and replaced the smaller line from the pump to the carb. Also replaced the pump itself with a new pump.
I did test the original pump by pulling the fuel hose from the carb and gave the rope a small pull. Gas squirted right out so it was pumping, but I thought perhaps when connected it was unable to push it all the way into the carb. I was still praying for it to be just a simple fuel pump issue. One of the easiest repairs, so like I said, I replaced it.
That did not help at all. Same problem. When I was at the marine shop I picked up a can of Sea Foam carb spray and a can of Sea Foam fuel additive. I used the spray by squirting it into the air intake (after I removed breather). (did not use additive so far) Turns out I am able to keep the motor running, albeit very rough and with crazy smoke, by spraying the Sea Foam cleaner into the throat. I did not do this a whole lot because I did not want to risk damage due to possible lack of lube in cylinders. I then let the motor stall, sprayed more cleaner, let sit, ran through, no help.
Now I have taken the carb off and am waiting for a rebuild kit to arrive. I got the one with a float included.
QUESTION: Does the 1988 originally come with a cork float? The one that has been in this carb is black and does not appear to be cork like the ones I have seen on older models. I am wondering if this carb has been redone before.
The carb that I have is the plastic top and plastic bowl. In the bottom of the bowl there was a slight film of sludge, nothing I would consider gritty. There are some darker colored areas here and there (shall I call it varnish?) inside the body but not bad.
The float needle seat was probably the most colored. Varnish all around it. The needle had some color to it as well. I am hoping this was the problem. The needle perhaps getting stuck in its seat once the float pushes it in and preventing fuel from entering. I dunno, wishful thinking I guess.
I am soaking the body now for 24 hours in carb cleaner. I am also looking for some diagrams so that I can locate each of the holes that I need to clean. I read that a thin piece of wire works well. I do not have an air compressor but I am considering getting a small can of compressed air (the kind you would clean a computer with) to blow in the holes.
I will post back with the results of the carb rebuild once it I am done (parts are due Friday or Monday if eBay seller fills the order as descibed).
My main concerns at this point:
Obviously worried that this wont fix the issue and that it is a greater problem, worst case scenario I have read is that a leaking "lower crank seal?" may not be allowing a vacuum to pull fuel into system.
Also read something about bad piston skirts creating a lack of fuel. I don't mind rebuilding a carb (kinda fun) but not sure about pistons and cranks. That makes me a little nervous.
You know...they say when you are sick, never look up the symptoms on the internet because by the time you are done reading you will have convinced yourself you only have 3 days to live. I am trying my best not to do that with this motor.
But just in case, tell my family I love them. (ok...now the post just got a little creepy!)
I appreciate anyone who would like to chime in.
Thanks for reading,
Chris - LouisvilleFisherman