Buy Johnson Outboard Parts

Announcement

Collapse
No announcement yet.

2000 J70PLSSD no spark #3 cylinder

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • 2000 J70PLSSD no spark #3 cylinder

    I bought a 70 hp for my 1650 fishhawk. the Engine did not run or idle well and eventually would not run at all. No spark. I diagnosed a bad timer base and replaced it. Now I have spark on #1 and #2 but 3 is dead. I switched the #1 and #3 coils and plug wires but #3 is still dead telling me it is not the coil.

    At this point I think I have a bad power pack or possibly a bad stator. I think the power pack controls the firing on the three cylinders and is my most likely the culprit.

    The power pack OHMed out properly. The stator ohmed out at 735 on the Brown to Brown/Yellow and 410 OHMs from the Orange to Orange/Black. The trouble shooting guide from CDI says the stators OHM should be between 450 and 550 OHMS. I cannot measure DVA.

    My question is can a bad stator cause just one cylinder to not fire while the others work or does this mode of failure point to the power pack.

  • #2
    A failing stator would not cause a singular problem such as you mention.

    That would pertain to a timing sensor, a power pack..... BUT more & most likely the following failure.

    ********************
    (Electrical Pins/Sockets - Poor Connection)
    (J. Reeves)

    The electrical rubber connectors that house a series of Pins and Sockets within them have a flaw which can easily be overlooked. The the pin or socket (or both) has been known to be pushed back slightly when pulling them apart and pushing them back together when replacing a component or doing test work.

    Also, the wire that is attached to these pins and sockets has been known to break away from the pins/sockets which results in either a very poor or no connection at all. I've found many instances where the wire is held tight in the rubber connector by pure friction but in reality is not making any connection.

    Be sure to check all of those rubber plugs for the proper pin/socket position and wiring attachments.

    ********************

    Comment


    • #3
      Thanks for your response Joe. I did check the connectors per your suggestion and found the black and white wire going to the thermostat was pushed back. A good thing to find now but I don't think that would cause one cylinder to cut out? The others seemed tp be positioned properly and my OHM readings were good on all the tests I ran so I think wire to pin connections are all good. I am going to buy a DVA adaptor so I can measure DVA and see if that shows anything I am missing with the OHM testing. I am assuming the rectifier would not be a suspect in this single cylinder miss scenario would it? Thanks in advance for your response.

      Comment


      • #4
        In reading over your latest entry, the problem would need to be either a faulty timing sensor or powerpack to affect just #3 coil (a proven good coil).

        Timing senors should all read the same to be eliminated... the power pack? <-- Frankly, it has always been easier for me just to replace it rather than to go thru the trouble to test it (parts on hand as test equipment)... but for the individual, I know, it's a expensive gamble.

        However, it all goes back to the saying of (sort of)..... "If all other systems check out, the one system remaining"........ I'm sure you know the original saying.

        Also, if it came to that some other weird flunky thing was to blame... having a spare pack and the tools to change it would be worthwhile to have in your on-board toolbox as those things usually fail at the damnest times.

        Comment


        • #5
          Originally posted by Joe Reeves View Post
          In reading over your latest entry, the problem would need to be either a faulty timing sensor or powerpack to affect just #3 coil (a proven good coil).

          Timing senors should all read the same to be eliminated... the power pack? <-- Frankly, it has always been easier for me just to replace it rather than to go thru the trouble to test it (parts on hand as test equipment)... but for the individual, I know, it's a expensive gamble.

          However, it all goes back to the saying of (sort of)..... "If all other systems check out, the one system remaining"........ I'm sure you know the original saying.

          Also, if it came to that some other weird flunky thing was to blame... having a spare pack and the tools to change it would be worthwhile to have in your on-board toolbox as those things usually fail at the damnest times.
          I was going to just order the power pack but suffer from cheapprickitus. So I bought the DVA to check the outputs. thanks for your help and I will post again with the "final solution"

          Comment


          • #6
            I wish I could point my finger at the guilty culprit but you're very clear in what you've been doing and have really covered all the bases in such a manner that I don't have any doubts about your trouble-shooting. Everything you've done has eliminated everything except the electronics within the powerpack. Frankly, I never had a problem with the points system and have often wondered why OMC changed over to solid state. What was worse... changing the points/condensers occasionally ($) or the pack and/or related parts ($$$)?

            Comment


            • #7
              No idea where I am going on this site. No help in how to post an inquiry. I need info on replacing starter pinion on 1966 6 hp Johnson. No idea where to go to find it as navigation here seems impossible.

              Comment


              • #8
                Originally posted by OLDGOSPELMAN View Post
                No idea where I am going on this site. No help in how to post an inquiry. I need info on replacing starter pinion on 1966 6 hp Johnson. No idea where to go to find it as navigation here seems impossible.
                NO, not impossible. Go back a page, look on the left hand side about 6" from the top of thew page... a black block with white print is there that states "New Topic". Simply click on that and you're on your way.

                To answer your question, the gearcase needs to be drained, then the skeg removed to get at the pinion gear. How do you know the pinion gear needs replacing.

                DO NOT reply here... Start your own topic under your own name so-as to keep things straight & proper. (Joe)

                Comment


                • #9
                  Originally posted by Joe Reeves View Post
                  I wish I could point my finger at the guilty culprit but you're very clear in what you've been doing and have really covered all the bases in such a manner that I don't have any doubts about your trouble-shooting. Everything you've done has eliminated everything except the electronics within the powerpack. Frankly, I never had a problem with the points system and have often wondered why OMC changed over to solid state. What was worse... changing the points/condensers occasionally ($) or the pack and/or related parts ($$$)?
                  So I got an DVA (
                  Electronic Specialties 640 DVA Adapter $31.00
                  )and took measurements and found the power pack checked out along with the Timing base checking out. The engine was now magically firing on all cylinders when I reconnected the plugs from the PP to the timing base.
                  I went back over the pins and did not find any mr obvious problems. Some of the female pins might have been expanded a little so I compressed them a little. I worked on setting the timing and found the timer base would only advance to 12 deg BTDC when the manual calls for 17 deg. That was my 3rd consecutive timing base from CDI that would not allow me get within the timing window for this engine. The first 2 were too advanced and I could only get to 2 BTDC not the 4 ATDC in the manual at idle. This time the base was too retarded and would get 4ATDC at idle but did not work at full throttle getting 12 deg instead of 17.
                  Yesterday they sent me another one that worked. So far with muffs on it seems near perfect. Joe I think either you were correct about the wiring/pins or the problem will turn out to be intermittent with the power pack and I will be replacing it.
                  I plan to run the motor this weekend to verify the ignition system continues to work and to tune carbs in the water since I am only running it on muffs so far.

                  Comment


                  • #10
                    Well, at any rate I'm glad to hear that the engine is running normally. The problem with the pin/socket setup is that it's really a friction connection and a corrosive wall can build up between the two (my theory anyhow). More than once I've yanked a few apart, maybe found one socket pushed back slightly but not far enough to break contact but realigned it anyway... and in shoving them all back together... the problem vanished.

                    And if asked... what did I do to correct it? I'd probably have a blank stare and a "Damned if I know" on the tip of my tongue as moving that socket a sixteenth of an inch wasn't correcting any make/break type problem. It's a more desirable type connection that the old more reliable terminal strip connection for obvious reasons (no dropping tiny screws overboard for one)... but charging a customer a hours labor for pulling one of those things apart and shoving it back together is pretty hard to explain if one tells the truth.

                    Yeah, by the time one gets the golf cart or whatever type vehicle hooked up to the boat, gets the rig in in the shop, trouble shoots the engine, (repairs nothing), runs it out and double checks... an hour is shot easily, but still.... some real funny looks are aimed at us.

                    Comment


                    • #11
                      If anyone is interested this DVA plugs into most meters and will allow you to diagnose ignitions systems(power packs, timing bases). very simple. It is called Electronic Specialties 640 DVA. On amazon including shipping for $31.00.

                      Comment


                      • #12
                        I am at my wits end. Took the boat out to test run and found the engine idled well but had no power and could only get 3,400 rpm and could not plane. Started pulling plug wires and testing performance and found #3 cylinder dead so I put my spark tester on #3 and opened it up 5/8" and it was jumping the 5/8" gap with no problem. I have already switched the #1 and #3 carbs since #1 was working before and the problem did not migrate with the carb. I drove home to do some testing and tested compression again and it was 135psi. When I took out the #3 plug to test compression it was fuel soaked. I even wrote the top dead center location of each cylinder on the flywheel and verified the timing was correct on #2 and #3 and they were. While I was on the water at full throttle I could see the carbs working and watched the fuel from each carb flow into the air stream and mix. All three carbs appeared to be providing the same amount of fuel. Despite the spark seeming to be fine I think I am going to replace the power pack as suggested earlier. Any thoughts would be appreciated.

                        Comment


                        • #13
                          Faulty ignition on #3 seems to be the problem as when you switched carbs 1/3, the problem stayed with #3 cylinder.

                          However, your mention of a fuel soaked cylinder has me wondering.... I assume your engine has a VRO. Is it #3 crankcase area that powering that fuel pump? If so, remove the pressure/vacuum hose from the pump temporarily, then pump up that fuel primer bulb to see if perhaps a diaphragm is letting the fuel mixture into that hose. If so, it would be like running the engine with the choke butterfly closed on one carburetor. Far fetched maybe, but.......... Just a thought.

                          Comment


                          • #14
                            Originally posted by Joe Reeves View Post
                            Faulty ignition on #3 seems to be the problem as when you switched carbs 1/3, the problem stayed with #3 cylinder.

                            However, your mention of a fuel soaked cylinder has me wondering.... I assume your engine has a VRO. Is it #3 crankcase area that powering that fuel pump? If so, remove the pressure/vacuum hose from the pump temporarily, then pump up that fuel primer bulb to see if perhaps a diaphragm is letting the fuel mixture into that hose. If so, it would be like running the engine with the choke butterfly closed on one carburetor. Far fetched maybe, but.......... Just a thought.
                            Great suggestion, I just checked that and not a drop came out. One thing thou came to my mind was the no oil light came on several times. Does that cause a limp mode. I had to pump the oil pump bulb and it would go away. I think I might have air in the line because when I hooked it up i just pumped the bulb with out making sure the air was out.

                            Comment


                            • #15
                              If air is suspected in the oil line, the only thing you can do is to go thru the priming sequence as follows... otherwise the air just keeps moving around.

                              ********************
                              (Priming The VRO Pump)
                              (J. Reeves)

                              When hooking up or installing a VRO whether it is a new or original VRO pump, it must be primed in order to dispel any air that might be in the oil line.

                              Have the Oil line attached to the engine fitting BUT detached from the VRO. Add a piece of fuel hose if necessary to the oil line so that it can be aimed into some sort of container.

                              Pump the oil primer bulb, catching the oil flowing out of the line into the container until you are absolutely sure that you have rid the oil line of every bit of air that might have been trapped there.

                              Now, connect the oil line to the VRO and secure it. When the oil line is secured, apply pressure to the oil primer bulb ONE TIME only. That's it.
                              ********************
                              Last edited by Joe Reeves; 07-15-2019, 06:59 AM.

                              Comment

                              Working...
                              X