Engine Timing

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  • siii8873
    Overdrive
    • Jul 2007
    • 1013

    Engine Timing

    I completed my crank / crank bearing rehab on the 2.25 petrol. All the work was with the crank I did nothing with the camshaft.
    Before I closed up the oil sump I put the #1 cyl at TDC with the "P" on the camshaft orientated per the green bible. Assembled the timing chain assembly maintaining this orientation with the drive side of the timing chain tight. Was going to install the distributor so checked the orientation of the dizzy drive gear. It is off by ~90deg from where the book says it should be. I rotated the crank / camshaft and watched the valves.
    I placed a plug in the #1 cyl only so I could also feel the cyl compression. All looked correct, the exhaust valve opened,closed, the intake valve opened, then closed, the cyl started compessing and the pointer came around to TDC. The "P" was right where it should be but the dizzy drive gear is off as noted. What am I missing?
    BTW the camshaft was replaced by the PO with a performance cam if that makes any difference. Pictures attached.
    Last edited by siii8873; 04-20-2011, 06:23 PM.
    THING 1 - 1973 88 SIII - SOLD
    THING 2 -1974 88 SIII Daily Driver - SOLD
    THING 3 - 1969 88 SIIA Bugeye Project
    THING 4 - 1971 109 SIIA ExMod - SOLD
    THING 5 - 1958 109 PU
    THING 6 - 1954 86" HT
  • Alaskan Rover
    Low Range
    • Apr 2010
    • 54

    #2
    Where the heck is your starter dog for the hand crank?? Gonna need that.

    If you didn't change out the cam, I see no reason why the distributer drive gear would have changed by itself. I'd put a big pipe wrench on that nut where the starter dog used to be and manually put the engine through its paces with all plugs out. Make sure all 4 cylinders have their compression stroke where they ought to be, and is exhausting and intaking as it should be.

    Your valve-train is back on, right? If it is, give it a tappet clearance check as per the manual's instructions. If the tappets open and close in the right sequence, you can assume that everything is as it should be for firing up. Put the valve cover on, drop in the distributer and all the other ancillary gear and she should turn over smartly. If the tappets are sequencing right, then you can assume the distributer should drop in as it sets now. If it doesn't...take it back out, and move the crank by hand and watch down inside the distributer drive gear, you should see it rotate at camshaft speed. If it doesn't...well then you're in a heap o' trouble.
    1970 Series IIA 88".,...the REAL Chitty Chitty Bang Bang.

    Comment

    • siii8873
      Overdrive
      • Jul 2007
      • 1013

      #3
      I didn't disturb the valve train/head either. All I removed / worked on was the crank. This of course required removing the timing chain. I didn't check the orientation of the cam / crank shaft before disassembly.
      I agree that I do need to get a starting dog. That is not effecting anything the crank pulley is on a keyway.
      I have attached a picture of the distributor before disassembly. I'm going to see how this matches the orientation of my other 2.25. Maybe it was like this before and the wires are rotated on cap to compensate.
      THING 1 - 1973 88 SIII - SOLD
      THING 2 -1974 88 SIII Daily Driver - SOLD
      THING 3 - 1969 88 SIIA Bugeye Project
      THING 4 - 1971 109 SIIA ExMod - SOLD
      THING 5 - 1958 109 PU
      THING 6 - 1954 86" HT

      Comment

      • siii8873
        Overdrive
        • Jul 2007
        • 1013

        #4
        picture
        Last edited by siii8873; 04-20-2011, 06:23 PM.
        THING 1 - 1973 88 SIII - SOLD
        THING 2 -1974 88 SIII Daily Driver - SOLD
        THING 3 - 1969 88 SIIA Bugeye Project
        THING 4 - 1971 109 SIIA ExMod - SOLD
        THING 5 - 1958 109 PU
        THING 6 - 1954 86" HT

        Comment

        • Terrys
          Overdrive
          • May 2007
          • 1382

          #5
          Im going blind, but even still, looking at the 2nd picture of your first post, I don't see that you have the distributor drive adapter installed. I can see the index key, down in the splined hole, and the offset slot in the drive adapter is in the same orientation as the index spline, so what I am seeing is that your gear IS in the correct location, and pointing towards the No.1 cylinder. So, in answer to your question in red letters, I think you're missing your distributor drive adapter.

          Comment

          • rosims
            Low Range
            • Jun 2010
            • 71

            #6
            I think you are right, the adapter is missing, it may still be on the bottom of the distributor, the adapter will move the slot about 90 degreees. It looks like the wores are in the correct spot on the distributor. I can take a picture of mine, if you like, I just built my engine but have not put the ditributor in yet.
            sigpic
            2006 LR3
            1967 109 Station Wagon
            M37B1
            M38A1

            Comment

            • siii8873
              Overdrive
              • Jul 2007
              • 1013

              #7
              In the second picture shouldn't the offset slot in the distributor drive gear be facing toward #1 cyl ? I do not think there are any additional parts that install between what you see and the distributor. The slot shown in the picture drives the distributor shaft via it's drive dog. This all looks 90 deg off to me compared to the maintenance manual.
              This engine was rebuilt before I owned it. It had a new cam shaft installed. Could this drive gear have been installed 90 deg out at that time? I do not know how it it indexed to the camshaft drive gear if at all.
              THING 1 - 1973 88 SIII - SOLD
              THING 2 -1974 88 SIII Daily Driver - SOLD
              THING 3 - 1969 88 SIIA Bugeye Project
              THING 4 - 1971 109 SIIA ExMod - SOLD
              THING 5 - 1958 109 PU
              THING 6 - 1954 86" HT

              Comment

              • siii8873
                Overdrive
                • Jul 2007
                • 1013

                #8
                Romas, Terrys,
                you guys are correct I went out and pulled the distributor and the adaptor your talking about was on the bottom of the distributor shaft and puts everything in the correct orientation.
                I didn't see this part listed anywhere in the green book distributor section.
                Thanks a bunch
                Bob
                THING 1 - 1973 88 SIII - SOLD
                THING 2 -1974 88 SIII Daily Driver - SOLD
                THING 3 - 1969 88 SIIA Bugeye Project
                THING 4 - 1971 109 SIIA ExMod - SOLD
                THING 5 - 1958 109 PU
                THING 6 - 1954 86" HT

                Comment

                • Terrys
                  Overdrive
                  • May 2007
                  • 1382

                  #9
                  Originally posted by siii8873
                  The slot shown in the picture drives the distributor shaft via it's drive dog.
                  That slot show is not the drive slot, thats for oil I think.
                  oops, just saw you found the missing piece to the puzzle. phew, I can still see!

                  Comment

                  • printjunky
                    3rd Gear
                    • Jul 2007
                    • 325

                    #10
                    I have to bump this because I think I'm actually having the problem Bob thought he was having.

                    After installing a new cam, checking and double checking everything (correct stroke at TDC, correct crank/cam gear alignment, etc, etc) It appears my distributor gear is 90 degrees off.

                    The first attachment is the dizzy gear without the adapter installed, the second is with the adapter installed.

                    My question is the same as Bob had, and the only thing I can think of. Is this a case of the dizzy gear being engaged with the cam 90 degrees off somehow? Obviously the gear housing only goes in one way (held via the grub screw through the hole in the housing). And there's nothing I can find mentioning it (much like said grub screw) in my manual.

                    Comment

                    • printjunky
                      3rd Gear
                      • Jul 2007
                      • 325

                      #11
                      Well, I'm sorely disappointed that I'm not at (with my Rover) the British car show happening right now about 200 yards from my house. http://qcbac.home.mchsi.com/index.htm

                      I worked the vast majority of available hours, outside until it was dark and I was getting eaten alive, and given up 95% of every weekend for the past month to fix my broken cam so I could drive down to this show for the first time. And still no luck. Again, very demoralizing.

                      I guess for the time being, I'll put it back together and just change the wires on the distributor so that #1 goes to #1. The engine is base-timed correctly, it appears (ie: cam/crank in sync), so all else that really matters is when the rotor gets to a contact in the cap, that spark goes to the correct cylinder.

                      Comment

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