Engine to chassis ground

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • DGG
    2nd Gear
    • Nov 2006
    • 304

    #16
    Originally posted by SafeAirOne
    The coil is fine. My lengthy reply about how the system works was primarily to give you the opportunity to have one of those "AhaaaHa!" moments, when you realize that the points need to open and close to make the engine go.

    Have a look at the procedure I copied out of the workshop manual and posted immediately before your latest query. Start at step #7.
    Great. Thank you for your help.
    Doug
    61 Series II 109 SW
    95 RR County LWB
    06 Range Rover
    98 Discovery LE

    Comment

    • DGG
      2nd Gear
      • Nov 2006
      • 304

      #17
      So I have a gap now between the two contacts, but still no start, and no spark that I can see.
      Doug
      61 Series II 109 SW
      95 RR County LWB
      06 Range Rover
      98 Discovery LE

      Comment

      • antichrist
        2nd Gear
        • Mar 2009
        • 272

        #18
        Did it ever run? Did you replace the points?
        If the points aren't installed correctly they will short to ground. There's an insulator that has to be fitted correctly.
        Tom Rowe

        Four wheel drive allows you to get stuck
        in places even more inaccessible.

        62 88 reg
        67 NADA x2
        74 Air Portable - The Antichrist (tag 6A666)
        95 D1 - R380
        95 D90 - R380
        97 D1 - ZF

        Comment

        • DGG
          2nd Gear
          • Nov 2006
          • 304

          #19
          Originally posted by antichrist
          Did it ever run? Did you replace the points?
          If the points aren't installed correctly they will short to ground. There's an insulator that has to be fitted correctly.
          It has never ran since I bought it 10 years ago. I'm in the middle of a frame off restoration, and am at the point of hooking things up to start it. It is not ready to drive yet though, but I just wanted to see if I could get it started. The distributor is the original, but new cap, rotor, points and condenser. Also new coil, leads and spark plugs. I would say that it hasn't run in 20 years.
          Doug
          61 Series II 109 SW
          95 RR County LWB
          06 Range Rover
          98 Discovery LE

          Comment

          • yorker
            Overdrive
            • Nov 2006
            • 1635

            #20
            It has been at least 20 years so century Gary Foster drove that 109. Double check the points. I don't remember what distributor that had on it but I once assembled mine and put the insulator in the wrong spot as Tom mentioned and it was frustrating. Relatively easy to diagnose with a test light though. Also don't forget to turn your ignition off when done. You can melt the points otherwise. I did that once and got stranded in the cemetery over in Edmeston... had to make some from scratch to get home. Fun times.
            1965 SIIa 88",1975 Ex-MOD 109/Ambulance, 1989 RRC, blah, blah, blah...

            Land Rover UK Forums

            Comment

            • DGG
              2nd Gear
              • Nov 2006
              • 304

              #21
              Thanks Matt. It has the original 25D distributor in it, but the points, condensor, cap and rotor are new. I'm getting 12V at the point contact with the points open. It's probably something simple, I just don't have enough experience to see it.
              Doug
              61 Series II 109 SW
              95 RR County LWB
              06 Range Rover
              98 Discovery LE

              Comment

              • yorker
                Overdrive
                • Nov 2006
                • 1635

                #22
                I'm confident it is something simple. Get a test light and go from there. Some tips here:http://www.minimania.com/Troubleshooting_Lucas_Points
                1965 SIIa 88",1975 Ex-MOD 109/Ambulance, 1989 RRC, blah, blah, blah...

                Land Rover UK Forums

                Comment

                • SafeAirOne
                  Overdrive
                  • Apr 2008
                  • 3435

                  #23
                  This is a fairly simple system. To maintain the system, you really should know how it works and what each component's role in the system is.

                  This is one of the best and most thorough explanations of the theory of operation of a points-type ignition system I could find on YouTube:



                  Once you understand how the system operates, you'll be able to test your non-functioning system in a logical manner till you find the problem. You'll want to be able to test to see if there is an electrical path between certain things in the system and you'll need to be able to test for voltage at certain places in the system.

                  For example, you've got to realize that with the points OPEN, one contact (the one that is NOT connected to the capacitor/condenser) will still be grounded (there will be an electrical path to the metal engine) when the points are open, while the other contact (the one that's connected to the capacitor) MUST NOT go to ground (must NOT have an electrical path to the metal on the engine), otherwise the circuit will never be broken, even with the points wide open because the electricity will still have a path to ground, causing the system NOT to work.
                  Last edited by SafeAirOne; 08-11-2015, 05:03 PM.
                  --Mark

                  1973 SIII 109 RHD 2.5NA Diesel

                  0-54mph in just under 11.5 minutes
                  (9.7 minutes now that she's a 3-door).

                  Comment

                  • DGG
                    2nd Gear
                    • Nov 2006
                    • 304

                    #24
                    At this point, I don't care if I come across as a moron with regards to this subject. I went on the link that Matt(Yorker) listed and followed the tests, and I can get a spark on a test spark plug through test 4. I have some seemingly stupid questions.

                    1. I'm getting 12v on the condenser side of the points with the points open and closed. Is this supposed to happen?

                    2. How does the rotor fit on? Mine seems to spin freely. How is it supposed to be at the ignition terminal in the cap when the points are open. Do you get the points to open and make sure that the rotor arm is in line with one of the contacts in the cap?

                    I'm really not stupid.
                    Doug
                    61 Series II 109 SW
                    95 RR County LWB
                    06 Range Rover
                    98 Discovery LE

                    Comment

                    • SafeAirOne
                      Overdrive
                      • Apr 2008
                      • 3435

                      #25
                      Originally posted by DGG
                      1. I'm getting 12v on the condenser side of the points with the points open and closed. Is this supposed to happen?
                      Yes, the condenser side of the points should have 12v whenever the ignition switch is on. The other side of the points should only have 12v when the points are closed.

                      2. How does the rotor fit on? Mine seems to spin freely. How is it supposed to be at the ignition terminal in the cap when the points are open. Do you get the points to open and make sure that the rotor arm is in line with one of the contacts in the cap?
                      Generally, that takes care of itself. The rotor only fits on the distributor shaft one way, with the flat in the hole in the rotor matching up with the flat on the shaft. There may be a small bit of play/slop in the distributor shaft, but that shouldn't matter.

                      The theoretical way it should work is that the points open up as the contact on the rotor passes one of the contacts on the underside of the distributor cap so that pulse of high voltage that occurs when the points open up will immediately have somewhere to go.

                      I'm really not stupid.
                      You'll be fine--It's just a matter of getting used to how the thing works. You'll be an ignition system expert by the time you get this engine running.



                      That flow chart that Yorker linked to is pretty good.

                      Are you getting spark at step 4, where you have a grounded spark plug connected to the center coil wire (the fat one) and you make/break the primary circuit manually with the ignition switch on, or just UP TO (but not including) step 4?

                      PS: Most painless way to ground the spark plug is to clamp one of the leads from a set of jumper cables to the spark plug threaded body and the other end of the same jumper cable to a ground or the - battery terminal. That'll save you from trying to hold it next to the engine to ground it (and you won't be zapping yourself).
                      --Mark

                      1973 SIII 109 RHD 2.5NA Diesel

                      0-54mph in just under 11.5 minutes
                      (9.7 minutes now that she's a 3-door).

                      Comment

                      • DGG
                        2nd Gear
                        • Nov 2006
                        • 304

                        #26
                        I'm not getting 12v on the other side of the points when the points are closed. And I am getting spark at step 4.
                        Doug
                        61 Series II 109 SW
                        95 RR County LWB
                        06 Range Rover
                        98 Discovery LE

                        Comment

                        • SafeAirOne
                          Overdrive
                          • Apr 2008
                          • 3435

                          #27
                          Originally posted by DGG
                          I'm not getting 12v on the other side of the points when the points are closed. And I am getting spark at step 4.
                          You were getting 12v on the condenser side of the points with the points open before. Now you're not getting 12v there when the points are closed?

                          1) Is the ignition on?

                          2) Are you probing with your meter on the 20v scale, with the red lead on the points contact and the black probe on a good bare metal ground on the engine?
                          --Mark

                          1973 SIII 109 RHD 2.5NA Diesel

                          0-54mph in just under 11.5 minutes
                          (9.7 minutes now that she's a 3-door).

                          Comment

                          • SafeAirOne
                            Overdrive
                            • Apr 2008
                            • 3435

                            #28
                            Just re-read your last post...

                            If you ARE getting spark in step 4 when you manually break the circuit and you're not getting 12v on the NON-condenser side of the points when the points are closed, then, presuming the ignition switch is on, electricity is, for whatever reason, not making it across the contact points when the contacts are touching each other (closed).

                            I would:

                            1) Make sure the ignition switch is on and re-test if it was off.

                            2) Make sure the little cam follower is completely off the little lobes on the distributor shaft and that the contact points are actually touching when the points are closed. Even a little open won't cut it in this position. (Ignition off when you're doing this!) Retest.

                            3) With the ignition off, take a tiny file or some sandpaper and clean off both contact points so that there is nothing inhibiting the flow of electricity from one contact to the other when they are fully closed (physically touching each other). [EDIT:] Oh, hey--This is step 5 of the flow chart test procedure!
                            --Mark

                            1973 SIII 109 RHD 2.5NA Diesel

                            0-54mph in just under 11.5 minutes
                            (9.7 minutes now that she's a 3-door).

                            Comment

                            • DGG
                              2nd Gear
                              • Nov 2006
                              • 304

                              #29
                              I will do this tomorrow. Thank you so much for your help.
                              Doug
                              61 Series II 109 SW
                              95 RR County LWB
                              06 Range Rover
                              98 Discovery LE

                              Comment

                              • yorker
                                Overdrive
                                • Nov 2006
                                • 1635

                                #30
                                Any luck?
                                1965 SIIa 88",1975 Ex-MOD 109/Ambulance, 1989 RRC, blah, blah, blah...

                                Land Rover UK Forums

                                Comment

                                Working...