Cockshutt 2. International 2. John Deere 2. Massey Ferguson 2. Massey Harris 2. Minneapolis Moline 2. Oliver 2. All New Parts Steiner Exclusives 5. Electrical Parts Engine Parts 7. Wipe off any oil that may have been pushed out of the bushings. Install the points loose. The points have two main pieces. There is a base plate with fixed contact, and a movable contact arm held in place with a small cotter-pin. The base plate has a center slot that fits over a bolt head, then is secured in place with a screw at each end.
Leave those screws slightly loose for now. That center bolt head is an eccentric cam that is used to set the point gap. Turn that screw head, and watch the point base plate move back and forth. The main reason we left the timing screw out is so we can rotate the breaker plate far enough to get a screwdriver on both screws that attach the points spring and condenser contact. Just rotate the plate until a screwdriver will work thru the hole in the top of the distributor body.
Don't install the timing plate and screw yet. Carefully inspect the installation of the points spring, copper foils, condenser wire, and special top screw. The two screws that these items attach to must be completely insulated from the rest of the distributor metal. The arrows and red line in the photo above show where a copper foil strip connects the two terminals.
Make absolutely certain that nothing in that area can touch any other metal in the distributor. The special top screw may have been replaced with something else.
The screw was not available as a replacement part when I first created this rebuild page. The special brass screw can now be found at just8ns. Part No. The ones I've been making are a little different, but they work for me. Set the point gap to exactly 0. The manuals often state a range of 0. With the screws at either end of the points slightly loose, turn the eccentric screw in the middle to set the correct gap. Tighten the screws at each end.
Check the gap again to make sure the points didn't move. They usually do. If they moved open or closed, loosen the screws and adjust the points slightly more or less than perfect, so when the screws are tight the adjustment will be perfect.
This process nearly always takes a few whacks. If either points screw is stripped, the fix is to replace with a slightly larger diameter screw. The replacement will be a very short length screw.
That length should not any longer than necessary to engage the threads in the top plate. Longer screws will interfere with the rotating advance weights below the top plate. Screws that are too long can be cut off and used. If your top plate already has the larger diameter screws, it may be time for a new top plate assembly. If the tractor was running ok and all you did is replace the points, the timing is probably ok right where it is, but it only takes a minute or two to check.
Less than that if you are fortunate enough to have a jig such as the one made by The Old Hokie, Dan Allen. Browse the N Board at ntractorclub. Once set, the timing should not change. However, low quality replacement parts make it more and more important to check everything.
Some people have run into parts that simply do not fit right. There are cases where people had to enlarge holes or drill new ones to get a set of points to fit! Try to buy the highest quality replacement parts available. Return or throw away parts that do not fit right. The time inferior parts will cost often just ain't worth trying to use them.
It is not a good thing when we find ourselves modifying original parts to make inferior replacement parts work. Sometimes there are no other options. While you have the distributor on the bench, its easy to check and set timing.
The point gap must be set first before setting timing, so go back to the previous paragraph and do that if you skipped it. Place a straightedge on the wide side of the tang on the distributor shaft as shown in the photo. The distributor points should just be starting to open. If not, turn the timing plate until the points are just beginning to open.
This will remove any slop in the advance parts. That is correct for these engines. Is it just me or does this timing adjustment look like something the engineers came up with after the distributor was designed and hundreds were in production? It seems obvious that if timing had been considered prior to production, a timing mark of some sort would have been cast into the distributor body.
This looks like a big OOPS that generated a mountain of memos before someone came up with a solution that allowed production to continue.
The arrows showing distributor shaft normal rotation help prevent confusion when flipping the distributor from front to back. This is why we left the timing screw out when the breaker plate was installed.
Install the small timing plate and tighten the screw. I'm not that lucky. Most of the made in China replacement points available today are not exactly the same as the original points.
In many cases there will not be enough length to the timing slot to get the timing set correctly. There are two solutions. Buy a different set of points and start over - or - Disassemble the distributor, remove the timing plate, distributor shaft, and carefully file the timing slot longer in the direction it needs to go. I've done this a few times with a rat tail file in about 30 seconds. File a little more than necessary to allow some extra adjustment.
The cast housing material is soft and files away easily, so don't get carried away. This is one of the things that happens when points are not made exactly to specifications. Filing the slot to set the timing will move the special screw off to the side. This makes it more likely there will be problems getting good contact between the coiled springy terminal on the bottom of the coil and this screw.
Don't get turned around flipping the coil over and bend anything the wrong way. Bend the coiled terminal by prying between the individual coils so the solder joint does not come loose. Here's another part I couldn't buy, so I made a few. When the timing slot has to be filed, the original timing plate can become too short to completely cover the slot. It turns out 16ga exhaust pipe is the correct thickness. Cut to lengths just over 1" long. Drill hole for the timing screw offset to match the original and ofset to allow more plate to cover the slot.
Match curve to an original part or side of distributor body. Grind to final size by bolting a stack together with an original in the middle as a guide. Leave one side longer to cover the slot if necessary. Stamp timing marks in slightly wider side, aligned with the bolt hole.
Three marks was the best I could do with the stamping set I have. It should be possible to do 7 equally spaced holes like the original. This is good enough for me. The timing marks don't really serve any purpose if you time the distributor as shown in the manual. The marks might help jog my memory when these turn up in my parts bin several years from now. Before installing the distributor on the engine, use a test light or ohmmeter to check that the points are opening and closing electrically.
Place one test lead on the hollow screw where the condenser wire connects. Place the other test lead on the distributor housing. Turn the distributor shaft and make sure you can see the points open and close. Check wire connections and copper flex strip for shorts. Drag a point file between the points until any varnish is scraped off, and they are working.
TIP: A point file isn't really a file. A proper point file is really a burnisher. They are usually about 3 inches long, very flexible, with a square tip to help get it started between the points. A burnisher cleans and polishes the contact surfaces using normal spring pressure as it is drawn thru the points. Recently, a no-start condition with my side-distributor 8N was eventually diagnosed to a build-up of something on the points. They showed closed with a test light, but actually had some electrical resistance when closed.
There was just enough resistance the coil would not fire. This was not fixed until an actual fine tooth file was run thru the points to scrape them clean. Once they were showing zero resistance closed, the burnisher was used to remove file marks and polish the points. Problem solved, it started right up.
Don't ask how many times the points were checked and how many other things were cleaned or replaced before this problem was found. As mentioned previously, I have found it easier to reinstall the entire distributor fully assembled.
It's a little more difficult to get it past the belt and fan blades, but I find that easier than assembling the cap and coil after the distributor is on the engine. When installing the distributor, the slot in the end of the camshaft front of motor is offset. The tang on the distributor will only mate easily to the slot on the camshaft one way. If you have it lined up correctly, the distributor will fit flush to the motor and the two bolts will go in easy. If the tang isn't aligned and in the slot, the distributor will not fit flush to the front of the engine.
If you put the bolts in and force it, the casting on the distributor will break. These engines can be very sensitive to timing and need to be very close to dead-on Top Dead Center for it to start easily and run right. If the point gap is set perfectly and the timing is adjusted exactly as shown in the manual, they should start and run well. Miss just a little bit on either adjustment and you can "fix" it by making a slight adjustment to timing without removing the distributor.
Loosten the timing lock screw, shift the timing about half a mark, tighten the bolt and see if that helped. Never tamper with a vehicle's electrical wires while the vehicle is running or any electrical current is flowing through the engine compartment. Mark the engine mounting point. To make it a little easier to install the new distributor, it's a good idea to mark a location on the outside of the distributor housing where the distributor is mounted to the engine.
Choose a spot for which you can find a corresponding location on the new distributor. This can make it simpler to line up the new distributor's housing with the engine mounting point which you may also want to mark. Mark the position of the rotor. Be precise - the rotor in your new distributor will need to match this position exactly.
Remove the old distributor. Remove the bolts that hold the distributor housing to the engine. Carefully and delicately pull the distributor away from the engine. Note that it's easy to accidentally move the rotor when you remove the distributor - if this happens to you, use the position of the rotor that you originally marked as your reference point, not the position of the rotor after you remove the distributor.
Part 2. Recreate the marks you've made on your new distributor. If you haven't already done so, remove your new distributor from its packaging.
Make the same marks that you made on your old distributor on your new distributor. In other words, mark your old distributor's rotor position inside the housing of your new distributor and mark the location on the outside of the distributor that lines up with your engine's mounting point.
Ensure that the rotor is in the marked position before installing. As noted above, the position of the rotor in the new distributor must match the rotor position in the old distributor exactly or your vehicle won't be able to start.
Ensure your rotor is lined up with the marking you made. As you install the distributor, take care not to accidentally move or nudge the rotor.
Mount the new distributor on the engine. Re-fasten the distributor in the same spot as the old distributor, lining up the marked location on the distributor housing with the engine mounting point. Re-screw any screws or bolts as needed to hold the distributor in place.
Don't tighten these fasteners all the way - you'll want to be able to move the distributor very slightly by hand. Re-connect the distributor's wires and replace the cap. Connect each wire to the distributor according to the markings you made. Ensure that you fasten each wire in its correct place - each one should be re-attached in the location that corresponds to its original location on the old rotor.
Start the vehicle. Double check all of your connections and attempt to start the vehicle. If the vehicle won't start, but sounds "close", try adjusting the position of the rotor a tiny amount no greater than the width of the mark you made and trying again.
If the engine sounds less close to starting , adjust the rotor in the other direction. If it sounds closer to starting , continue to adjust it slightly in the same direction. When you get the vehicle to start, allow it to "warm up" until it idles smoothly. Adjust the timing. Stop the engine and put a timing light on the 1 spark plug.
Restart the engine. Adjust the timing by rotating the distributor housing by very small amounts. Be sure to follow the instructions specific to your vehicle which you located before replacing the distributor - as noted above, these instructions will vary from vehicle to vehicle. When you've adjusted your timing to the proper setting, tighten the fasteners you left slightly loose previously.
Take your vehicle for a test drive. You're all finished - test out your new distributor by putting your vehicles' engine through a variety of different accelerations. You may notice differences in the way your vehicle performs. If anything about your vehicle's performance seems out of order, take your vehicle to a mechanic.
Don't risk lasting damage by running your vehicle for long periods of time with distributor problems. I didn't mark where the old distributor was when I removed it. How can I tell where to put the new one? You'll have to bring your number one cylinder to top dead center tdc and adjust your rotor to where it's slightly before the number one plug wire on the cap. That should get you in the ballpark.
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