stumped on an 88 hp Johnson problem

[jbkk]

I posted a while back about my 1993 88hp outboard motor and its running problem. The motor has a noticeable miss at idle speed, then when trying to get on plane it takes off very slowly, until you get up at which time she'll take off. It's sounds like its not running on all cylinders and then at full speed it does. I have replaced the coils, plugs, plug wires, cleaned/checked the carburators (sp), fuel line, and still can't get rid of the problem. Just looking for suggestions if anyone has one on where else to look - thanks in advance for any help.

 

[Bear]

Re: stumped on an 88 hp Johnson problem

 

[DJ]

Re: stumped on an 88 hp Johnson problem

No mixture screws on that one.<br /><br />jbkk,<br /><br />How many rpm's will it achieve. A V-4 will plane a boat on three cylinders, but it will not reach full rpm. 4500-5500.<br /><br />When it is idling, remove one plug wire at a time. That may tell you which cylinder is not contributing.

 

[w@rboat]

Re: stumped on an 88 hp Johnson problem

HEY JBKK,<br /><br />I have that exact same problem. my motor is a 75 model 85hp Johnson v4. the method of pulling the plug works. MY number 3 cylinder is not firing hardly at all. I did the same things with the plugs, wires, and coils; and had the same results. And the boat does plane on 3 clinders but rpms are down. Top speed is now only 30mph.<br /><br />I am currently working on fixing that problem. i have narrowed it down to either the stator assembly or the power pack. I am going to run an output test on both of these as soon as i find the information on minimum output voltage from the charge and sensor coils along with the power pack. By the way you wouldn't happen to know the output ratings for those coils or power pack would you? or anyone?<br /><br />jbkk i will keep you posted on my results as soon as i get them so maybe you can save a little $$$.<br /><br />Get back with you soon!

 

[elisa191]

Re: stumped on an 88 hp Johnson problem

Hay guys I will save you the time of running the stator and power pac tests. If one bank of the v-4 runns then the stator is fine as neather side will fire right if it is bad. Replace the power packs... there cheap do both of them and then have fun. <br /><br />P.S. Save the good pack and keep it on the boat so you have a spear!<br /><br />Love Ya...

 

[jbkk]

Re: stumped on an 88 hp Johnson problem

Thanks everyone for the advice . I am going to try pulling the plug wires and then get power packs if neccessary as suggested - are they easy to install ? I am not even sure where they are but will hopefully figure it out and get back to catching some redfish.

 

[ledgefinder]

Re: stumped on an 88 hp Johnson problem

Sounds more like an intermittent sensor on your timer base to me. In any case, I think you're on the right track to measure the voltages and diagnose the problem, rather than just throwing expensive parts at it until it runs right.