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  • #26
    When you get a crankshaft ground, check it with the front and rear mains on V blocks. Use a dial indicator. Make sure the flywheel flange has no more than .0005 run out. also check center main for run out. They seem to have a hard time getting it right around here. To much run out on the crank flange is going to make it vibrate bad. To much on the center main is going to cost you the center main bearing way early.
    Last edited by George Miller; 03-19-2018, 11:27 AM.

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    • #27
      image_9958.png
      2 1930 Tudors

      Henry Ford said
      "It's all nuts and bolts"


      Mitch's Auto Service ctr

      Comment


      • #28
        Valve Specifications


        Lift .287" with .015" clearance

        Seat Angle 45º

        Seat Width 3/32"

        Stem Diameter .311"

        Valve Length 5.677"

        Head Diameter 1.537"

        Valve Opening Diameter 1-3/8"

        Port Diameter 1-3/8"

        Clearance, Exhaust Valves in Guides .002"

        Clearance, Intake Valves in Guides .001" to .0015"

        Valve Lifter Clearance .010" to .013"

        Lifter Diameter Clearance .0015"

        Valve Guides .3135" ID; .5938" OD; length 2.125" (early 2.375")

        Valve Spring 1.022" OD; free length 2-15/16"; comp. length
        2-1/14" (57-64 lbs.); tension (closed) 34 to 38 lbs.

        Valve Lifter A6500A (used with A camshaft), length 2.486";
        head diameter 1.117".

        Valve Timing Intake opens 7-1/2º before Top Dead Center; closes 48-1/2º after Bottom Dead Center. Exhaust opens 51-1/2º before Bottom Dead Center; closes 4-1/2º after Top Dead Center.
        2 1930 Tudors

        Henry Ford said
        "It's all nuts and bolts"


        Mitch's Auto Service ctr

        Comment


        • #29
          Leak-less rear main.

          If you want a leak less rear main you need a flat cap mating surface a little sealer on the cap sealing surface, If you are using shims make sure they are against crank shaft or the oil will leak by. sealer on the bolts going through the block, no bad end play (.002= .004 ) with the crank shaft, no bad blow by from pistons, and the right bearing clearance. Plus make sure you have the 3/8 drain tube, make sure it is in tight, if not it will let air in and there will be no vacuum to pull the oil out the rear main oil return. I like to use lock tight on the threads of the pipe, screw it in tight and point it in the right direction. Take out the soft plug in the cap, run a drill the same size as the hole in the cap. do this after the drain pipe is in. drill it the same distance as the old hole in the cap. Be careful to not drill through the end of the cap, clean it good. Put a new soft plug in. If you do all this right you will not have leaker. If you do have a leaker after all this a draft tube will help because you have bad blow by.
          Last edited by George Miller; 07-07-2018, 12:10 PM.

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          • #30
            Various engine pictures
            2 1930 Tudors

            Henry Ford said
            "It's all nuts and bolts"


            Mitch's Auto Service ctr

            Comment


            • #31
              Shim Information thread 2!

              Original Thread

              Ok, show of hands just how many of you have tried to separate a .001 shim from the bearing shim stock?

              I have NEWS!!

              I just figured a better way to do it without pealing them up like curley que. I have this tool that is called a "resistance solder machine" and basically what it does is has 2 wires which electricity is passed through to heat up an item, kinda like welding, only it is made for soldering.

              Now here is the trick part, I placed a block of shim between the tips and threw the juice to it, which smoked and while heating up the shims, burnt the stuff holding them together.

              Now, I know that only maybe one or two of you would even think of owning one of these, but here is the idea.

              Take your favorite charged up battery and hook some decently heavy wires to each terminal, say battery cables, and carefully hold the two cables against either side of the shims and it should heat the shims up enough to burn out the adherent.

              This should separate the plates. Now, say you break them all loose and want to place a few of them back together, easy peasy, just use a bit of finger nail polish between the plates and clamp it back together, the polish will hold them.

              I just found a small flaw in this idea, try to only heat it up enough to burn the stuff out, if you heat it too much, you could weld them together, like spot welding.
              "We do not stop playing because we grow old;
              We grow old because we stop playing ...
              NEVER Be The First To Get Old!" Pilfered from the MAFC SA Newsletter

              I JUST CAN'T FIX STUPID!!

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              • Mitch
                Mitch commented
                Editing a comment
                Thanks Wiz
                I think Chief has one of those solderers. Here is a tech thread on the subject

                https://www.vintagefordforum.com/for...4811#post54811

              • Keith True
                Keith True commented
                Editing a comment
                Heat up a piece of steel,any kind of scrap,probably 1/4 inch or thicker till it's cherry red.Throw the shim pack on it,push them down like a hamburger on a grille,and watch the thin shims curl up and away from the others.I have had some modern shim packs though that this had no effect on.

              • Patrick
                Patrick commented
                Editing a comment
                Good ideas. I've always had trouble separating the packs, so I just sand them.

            • #32
              I've used a magnifying glass, then scrape the edge with a razor blade until a corner starts to lift up.

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              • #33
                torch works the best shims stay straight

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                • #34
                  I always found individual shims come apart easier when bending same back and forth because of their having no shear resistance between individual pieces.

                  Similar to structural wood and/or steel beams carrying loads & Model A springs carrying loads ..... there is zero shear in centers of structural beams and Model A springs at the center bolt; however, shear and internal "sliding" forces occur further out at both ends when bending during deflection.

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                  • #35
                    The new shims of the past 3 years or so, are put together with a modern Glue. They are all but impossible to get apart with out heating to burn the glue out of the packs. I use a small propane torch to burn the glue away, and a small needle nose pliers to hold them with. Where the pliers holds the shim, the pliers jaws protect the glue, and will keep the pack together, if desired. Do it very slowly, only takes about 10 seconds, or less. When the flame stops, from the Glue burning, your done.

                    The shims that come as Main, or Rod shims are normally of .003, and .002 thousandths increments.

                    Herm.

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                    • #36
                      Timing Mark info

                      Here are pictures showing the front and back of the crankshaft gear, and it you look closely you will see the cam timing will be a little different if the gear is installed backwards. I took one engine apart with the gear on backwards.

                      Crank Gear 1.JPGCrank Gear 2.JPG
                      Attached Files

                      Comment


                      • 2manycars
                        2manycars commented
                        Editing a comment
                        In view of the fact that the timing mark is obvious, I wonder why someone would install it backwards. Additionally, that one seems to have a F on the front side. I guess everyone fancies themselves as a mechanic. Some are not.

                      • 2manycars
                        2manycars commented
                        Editing a comment
                        In view of the fact that the timing mark is obvious, I wonder why someone would install it backwards. Additionally, that one seems to have a F on the front side. I guess everyone fancies themselves as a mechanic. Some are not.

                      • H. L. Chauvin
                        H. L. Chauvin commented
                        Editing a comment
                        Above reply #2 question is interesting: "I wonder "why" someone would install it backwards."

                        I am sure many could offer more than one possibility ..... notice Tom did not say Why?

                        May be best to pass on trying to answer this question!

                      • Mitch
                        Mitch commented
                        Editing a comment
                        We had a car at the Gettysburg meet with a blown cam gear. We could not find a dot on the crank gear so we went by the key way .. ill find it and post up a link

                      • Mitch
                        Mitch commented
                        Editing a comment
                        We had a car at the Gettysburg meet with a blown cam gear. We could not find a dot on the crank gear so we went by the key way .. ill find it and post up a link

                      • Mitch
                        Mitch commented
                        Editing a comment

                    • #37
                      Generic list of things that cause engine knock

                      1. loose rod or main bearings
                      2. shrunk pistons from overheating
                      3. oversize piston hitting edge of head gasket
                      4. wrist pin loose
                      5. cam gear
                      6. valve lash
                      7. camshaft jack hammering back and forth due to failed spring in timing cover
                      8. improper timing
                      9. low oil level
                      10. failed oil pump
                      11. failed crank thrust
                      12. failed valve seat insert
                      13. FYI, if babbitt, loose or failed center main is common

                      Generic list of things to help troubleshoot

                      1. remove fan belt, run motor briefly to see if noise disappears
                      2. noise at idle? or under load
                      3. engine hot or cold?
                      4. what work recently performed on motor?
                      5. results of shorting out one cylinder at a time?
                      6. loosen 1/8 pipe plug from passenger side of block at idle and see if oil is coming out
                      7. Drain oil and look to see if any metal chunks come out
                      8. check crank thrust
                      9. remove side cover of timing gear and inspect gear teeth (don't forget the one pan bolt there!)
                      10. remove plugs and look at porcelain color. If very white, then burn too lean which can cause spark knock. (lean mixture fires early). Also check closely for shiney specks and flakes, if so this is bits of aluminum being blasted off the piston by too advanced timing
                      11. check timing. Zipper distributor on a HC head will be too advanced and knock
                      12. use of borescope

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