Exploring the Ford Starter from Front to Back COLUMN BY RICHARD R. VENSEL How It Works Let’s take this unit and simplify it to a basic electro- mechanical draw- ing. This drawing will be used for ref- erence throughout this article. See Figure | and the breakdown. Step 1: Power to the Starter. Battery current flows through field post L to coil C then through the points H to ground and through coil E to ground. This bypasses the armature and coils A, B and D, exerting maximum magnetic attraction to the movable pole shoe (G) to pull down, engaging the drive in the ring gear causing the points (H) to open. BREAKDOWN : Field Coil : Field Coil : Drive Coil : Field Coil : Holding Coil : Retaining Sleeve : Movable Pole Shoe : Contacts Armature Ground Brush (-) : Field Brush (+) : Field Post X: Solder or Weld Points CASS TOMmmMyaAW> Hectromechanical drawing of the Ford positive engagement starter viewed from the commutator end. Coil E develops approximately 300 ampere-turns of magnetic strength. Coil C develops approximately 7,000 ampere-turns of magnetic strength. Step 2: When the drive engages in the ring gear the points open and the engine cranks. With the points (H) open the current still flows through the hold- ing coil (E) to the ground. And through coils C and D, and A and B to ground through the field brushes (KK) and arma- ture (I) to the ground brush (J). Coil E still develops approximately 300 ampere-turns of magnetic strength. Coils A and B, and C and D develop approximately 2,100 ampere-turns of magnetic strength. Note: Approximately 600 amps per turns of magnetic strength are required to keep the movable pole shoe (G) seated so the holding coil (E) could never do the complete job. Immediate Results It appears from all the comments we received that there are still rebuilders who have yet to whip the problems with these units. Based on this response, we feel it would be beneficial to suggest some procedures that will create imme- diate results. When tearing down these units, wire or tie the shift lever to the field case and keep these two pieces together until final assembly. This simple process can really make a difference at final test. Inspect all weld or solder points X1 to X6 (referring to Figure 1, page 3). Points X1 and X2: Field coils to the field post. Remember this connec- tion must be able to handle all the cur- rent going through both the armature and the fields. It pays to clean it off and resolder it. Point X3: Holding coil to field post. This is not always accessable due to being connected inside the coil wrapping, but should always be tested. Point X4: Holding coil to case ground. This fine wire circuit should not only be tested, but also given a slight tug. This will ensure it’s not just making contact, but broken inside the insulation. Always be sure there is good connection at the field case. Point X5: Field coil to points. This can be one of the biggest problems. We suggest silver soldering this point if possible. Point X6: Positive brushes to the field coil. Since this is the most replaced part that is soldered or welded, it can be the weakest connection point. This point gets all the current just like the field post does and deserves as much if not more attention. We recommend silver solder- ing if possible. After assembly and before final test, observe the physical relationship of the shift lever and the field case. Figure 2 shows the shift lever C.E. sits slightly inside the field case where it should be. Figure 3 shows the shift lever C.E. sitting outside the field case. This posi- tions the movable pole shoe further out of the optimum magnetic pull of the drive coil, (C) Figure 1 and holding coil (E) Figure 1. In most cases this will be the unit you will have trouble with. When you find this your best bet is to substitute a shift lever that will sit lower in the case. Shift Lever Assembly The shift lever, although only a mechanical part, is the heart of the Ford starter working properly. The shift lever has been supplied in many forms over the years with a wide range of physical differences. What this means is that if you laid out 10 shift levers, you may only find two that were the same. Let’s look at the critical problem areas. Keep in mind that your best bet will be to keep OEM samples as standards. 1. Poor welding from the shift lever to the pole piece. 2. Different heights and configura- tions on the pole piece. 3. Note: The sleeve being formed wrong can also cause problems. The excess can be cut off allowing complete seating of the shift lever. 4. The height of the tang on the rear of the shift lever. 5. Improper spacing between the engaging arms (too wide normally). 6. Too much slop between the pivot pin and field case mount. 7. Improper spring tension. This spring should never be cut to try to solve a pull-in problem. 8. The pivot pin hole is not a