140 Johnson Starting problems

[pj_elia]

Re: 140 Johnson Starting problems

Thanks for the advice. All the connections screwed into the power pack are clean. They look new. The red plug connections look clean also, no visible corrosion. I ordered a powerpack and coils from an outboard recycler. I got used units because I could not justify buying a new powerpack without knowing definately what was wrong. <br /><br />I plan to do the carbs during the winter. I need a few more weekends before I put the boat away.<br /><br />PJ

 

[pj_elia]

Re: 140 Johnson Starting problems

Yesterday, I went to start the boat again just to see if its still running like the previous 3 days. I had not touched the boat other than turning the hose on and turning the key to start it. The previous 3 days it started right up. Yesterday, it would not start, I then checked for spark and could not get any. I did not touch anything on the boat, not even primed the fuel line. This inconsistancy leads me to believe the powerpack is the cause and I can't wait for it to arrive in the mail.<br /><br />PJ

 

[Tom Scully]

Re: 140 Johnson Starting problems

Getting good spark after disconecting the red plug indicates a problem in the ignition switch.<br />Corrision can build up inside the switch which causes the engine kill wire to become "partially grounded". <br />Check for any resistance between the black/yellow wire and ground, on the ignition switch, there should be none.<br />My 1978 115hp had similar problems with intermittant spark; the cause was a corrision filled ignition switch.

 

[pj_elia]

Re: 140 Johnson Starting problems

Well, I got a powerpack from a boat salvage place. I hooked it up and now I get spark only on the #3 cyclinder. Swapping the coils around verifies that only the #3 output gives spark. I guess the used power pack is also bad. I'll call the boat recyclers place tomorrow for a refund or a replacement. <br /><br />Tom,<br />Red plug has no effect on spark problem so I've ruled out the ignition switch. Thanks though.<br /><br />PJ

 

[MCM]

Re: 140 Johnson Starting problems

Hi pj,<br /><br />Unfortunately used elec. parts are always a risk.<br /><br />Hope they treat ya right<br />Mike

 

[pj_elia]

Re: 140 Johnson Starting problems

I talked to the salvage yard and he said the part came off a running motor. He said the stator might be bad. He was going to check with another mechanic who knows older motors better and get back to me. Do you guys think the stator could be the problem if I get good spark on one coil and not on the rest.

 

[pj_elia]

Re: 140 Johnson Starting problems

The yard called back and they are sending another power pack. He said if one bank of coils are sparking and not the other, than it could be the stator. I'll let you know in a few days how it goes.<br /><br />Paul

 

[87Aggie]

Re: 140 Johnson Starting problems

Could be your timer base sensor gap. Do a search on sensor gap adjustment for information on how to do this. R.Johnson has some great posts on how to adjust the gap. I have a '77 140 hp and I had spark only on 1 and 3, adjusted the sensor gaps and I'm back on the water. By the way, I also replaced the powerpack and stator and was still having the same problem. (My stator was definitely bad because it was oozing in a couple of places.)

 

[pj_elia]

Re: 140 Johnson Starting problems

Aggie,<br />If the powerpack does not solve it, I will be headed in the same direction as you. I'm going to look up those posts you mentioned.<br /><br /><br />PJ

 

[pj_elia]

Re: 140 Johnson Starting problems

Well, I got another powerpack from the boat recyclers and now I'm not getting spark on any cyclinder. I'm going to try swapping the packs again to verify that I get some spark with each of the others but to different coils. I'm not sure what to do next because I really thought the powerpack would solve it. Its hard to believe that I would get 2 bad powerpacks from the recyclers. I should have bought a new powerpack to begin with but now I have doubts that it will solve my problem.

 

[MCM]

Re: 140 Johnson Starting problems

PJ, <br /><br />I recently went through similar ign. troubles, replaced stator, power pack, coils, it seemed temp. sensitive, above a certain temp. I got spark below & nothing, as it turns out the timer base was bad.<br /><br />There are some tests you can do to see if your getting the proper OHM readings, if you've got a manual it will explain the procedure & readings you should be getting.<br /><br />Hope this helps,<br />Mike

 

[87Aggie]

Re: 140 Johnson Starting problems

You really need to try the sensor gap adjustment! I tried the powerpack swapping as well - with a new one, and got similar results as you're experiencing. I now have an extra powerpack in the event I ever need one - an expensive lesson learned!! Once you get the adjusting tool - you can get it here at iboats, shipping is more than the actual tool, but it's fairly easy to adjust the gap - you'll need a sharp scraping tool to remove the old epoxy and some new epoxy to set the nut after making the adjustment.

 

[pj_elia]

Re: 140 Johnson Starting problems

I swapped back to the original powerpack and got no spark. Previously I have spark to #2 only. I then went to the first powerpack I received from the recyclers and then again got spark only on #3. It would spark repeatidly when I started to crank but as I kept cranking, it would spark intermittently. I repeated this process and the results where the same every time with different coils. I only got spark on #3 and the frequency of the spark would deminish after a few seconds. <br /><br />I understand Aggie's point about checking the sensor gap but if the powerpacks were all good, why do I get different results with different powerpacks? I don't want to risk fooling with anything that I don't need to. <br /><br />At this point my options are either:<br />1. Buy a brand new powerpack and try it. <br />2. Buy a sensor gap guage and adjust the sensor gap<br />3. Take it to the dealer. <br /><br />What do you all think?? Any other ideas?<br /><br />PJ

 

[pj_elia]

Re: 140 Johnson Starting problems

Is there only one sensor gap guage listed in Iboats. Its pn#5539702. Is this one guage that fits all?

 

[MCM]

Re: 140 Johnson Starting problems

Paul, I don't think the sensor gap in you timer base is adjustable, even if it was or is you should troubleshoot the timer base first.<br /><br />This can be done by using an ohm meter and following the instructions in your manual, if the ohm readings are not within the expected ranges or if the sensor is grouded I don't think any amount of adjustment will help.<br /><br />Good Luck

 

[pj_elia]

Re: 140 Johnson Starting problems

MCM,<br /><br />I did the sensor High and low Ohm checks and I believe they passed. My multi-meter does not have a low ohm setting but I could see a slight resistance between the sensor coils on the high Ohm scale. Sensors were definately not grounded. They showed infinatey on the Ohm scale when doing the High Ohm test. <br /><br />Where would you go from here?<br /><br />Paul

 

[MCM]

Re: 140 Johnson Starting problems

Well Paul, Without a definative LO ohm reading you could be reading 5.0 or 50.0, when I figured out that mine was bad it was giving me readings that went from 80.0 to 150.0, just kept going up & down, it was suposed to be reading 15.0 +/- 5.0.<br /><br />So did you find the posts about gapping your sensor 87Aggie suggested? I'm pretty sure the manual says there not adjustable, but I'd guess that's not to say it can't be done. I'll be the first to admit I'm no expert on these motors.<br /><br />I gave you a link earlier that has alot of info on troubleshooting ign. systems. Here it is again along with a couple of others.<br /><br /> http://outboardparts.com/omc/troubleshooting/trublshtinghlp.htm <br /> http://outboardparts.com/omc/troubleshooting/troubleshooting1.htm <br /> http://outboardparts.com/omc/troubleshooting/troubleshooting5.htm <br /><br />Maybe you can find something there<br /><br />Good Luck & keep us posted

 

[rodbolt]

Re: 140 Johnson Starting problems

if you have the single pack with screw terminals you most likly have a sensor (timer base) or stator issue.<br /> its also possible you have a weak starter. if that motor cannot spin at least 300 rpm or so it wont spark. test with plugs out and then with plugs in. if it sparks with them out and not in correct the starter circuits.<br />call CDI 1-866-CDI-TECH and order booklet # wbk 2004calleds practical outboard ign trouble shooting, list price is 19.95. and oddly enough a bad rectifier can cause a no spark condition as well. the test for resistance from #1 to #3 sensor,with wires disconected should give 10-20 ohms, same with #2-#4. but a quick 15 min session with a DVA meter will positivly peg the defective component. its well worth the money