Johnson '93 9.9 surge

[ba_50]

What would cause a 92 Johnson 9.9 to surge? It seems to be the worst when going at slow speed. It comes and goes. Sometimes real bad and sometimes not.

Thank, Bob

 

[jbjennings]

Re: Johnson '93 9.9 surge

I've had a similar problem before and it was a bad coil, or it could just be a fouled spark plug. At worst, a bad power pack, but in my case I just had to replace the coil.
An expert will check in soon, hopefully, and they can probably give you a very accurate answer.
Your problem is intermittent, right? Sometimes it runs fine?
I'll be curious to hear your solution,
JBJ

 

[HighTrim]

Re: Johnson '93 9.9 surge

Have you done a spark test? You could have a faulty coil , PP, etc... as stated, and the surge you feel is the cylinder kicking in. When running, pull each spark plug wire, 1 at a time, with insulated tool of course, and listen to the RPMS. You should hear a noticable difference, if you dont, that cylinder is dead and the problem. You will then need to trouble shoot the reason you are losing spark. Or you could try in the driveway with an inline spark tester set to 7/16 of an inch. The spark should jump the gap with a stong blue ZAP!! The lack of spark will be either a faulty power pack or ignition coil. Extremely rare causes include a weak trigger magnet in the flywheel or a timer base. Start with swapping the coils , if the problem follows the coil, that is your problem and needs to be replaced. If the problem doesnt follow the coil, your PP may be to blame and would need to be tested as per your manual. Good luck.

 

[ba_50]

Re: Johnson '93 9.9 surge

The fellow we bought this motor from got it new and only used it about 3 times as a kicker motor. I cleaned the carb and put a new fuel pump on it last year. I have put 10-15 hours on it. I was running it too rich, but even so, the plugs weren't fouled. I swapped for two used plugs and I thought that solved the problem but it came back. It has a inline fuel filter. I have run sea foam through it too.

I don't know why there would be anything wrong with the power pack or coils unless sitting out in the Florida sun would damage them.

I can't seem to adjust the low speed needle and knob in the end of the throttle by sound. Sometimes it dies at idle and other times it won't. I assume that if it dies at idle, the mixture needle is too low. The only way to shut this one off is to pull off the safety switch. This should be another topic I guess.

Will try what you mentioned.

 

[mikesea]

Re: Johnson '93 9.9 surge

You say the only way to kill the engine is with safety switch.Its possible you have a problem with the kill switch grounding,disconnect the kill switch and the saftey lanyard,run and see if the performance is better,the kill switches do go bad,there should be easy disconnects

 

[ba_50]

Re: Johnson '93 9.9 surge

Mikesea

I can't find a kill switch on it. The knob on the end of the throttle is empty so I assume one goes in there?

Put two new plugs in this morning and it still surges.

 

[jbjennings]

Re: Johnson '93 9.9 surge

I'm not sure how your '93 is but my kill switch on my '99 30hp is the button the lanyard clip goes on. I just press mine in. The end of the throttle grip on mine is only an adjuster for the idle stop. It very well could be where your kill switch goes, however. The coils don't have to have a reason to go bad, they just do. Sitting out in the weather and having constant temp. changes like we have in the south from super hot out in the sun to quick cool downs at night can cause the darned things to mess up after a while. Like I said, mine's a '99 model and already had to have a coil. You do need to get your kill switch problem fixed. It very well could be grounding out as stated above.
Let us know when you solve it, I'm interested.
JBJ

 

[HighTrim]

Re: Johnson '93 9.9 surge

Bob is this a new motor to you? Do you have a manual? If not, it is a wise investment, and will pay for itself many times over. Check ebay or outboardbooks.com for a reprint. Im confused a little. First you said that the only way to kill it was to pull the safety switch, then said that you could not find it??? Test the spark first. The black /yellow wire is the kill wire. I believe you may have more than 1 problem here.

 

[mikesea]

Re: Johnson '93 9.9 surge

There have been many changes in the 9.9 -15 over the yrs.But,whatever kill switch(s) you have,disconnect them,test carefully ,see if problem is still there,use the choke to kill the engine if necessary,it sounds just like a ground leakage thru the switch,you should find 2 disconnect connectons where the wires from the switch enter the motor,you can also trace to see where it picks up the ground,one wire will connect to ground,but I lie to totally disco.the switch.It is a common problem.

 

[ba_50]

Re: Johnson '93 9.9 surge

Yes this motor is new to me and it is a 1992 J10Rena, not a 93. I checked out the parts on the evinrude website and it shows a kill switch on the right hand side of the motor. It looks like a black button that is flush and it doesn't work.

I tried the spark jump of 7/16". It arced all the way across on both plugs and the color was blue / orange.

I also pulled the plug wires and the power dropped about half on each.

Since I plan on keeping this motor I will get an OEM manual for it.

 

[ba_50]

Re: Johnson '93 9.9 surge

I believe I have solved the SURGE problem. It kept getting works, so I took the fuel pump apart. The diaphagms were ok but I noticed lots of fine granular dirt pieces on all the parts. I cleaned it up, put it back together and tightened the bolts.

The motor ran fine after that. I believe air was being sucked into the fuel pump through the sides, causing erratic operation. Hope this helps someone.