DISTRIBUTORS - GENERAL

One of the things I like about these old tractors is being able to fiddle with things like points. These old engines will usually start telling you they need service, LONG before they quit running. I get emails all the time from people that start out with something like, "my tractor was getting harder and harder to start, then...." Modern cars have spoiled us. We are losing the ability to pay attention. "Getting harder to start", means it's PAST time for service. I can't tell you if it's air cleaner, points, condenser, plugs, wires, cap, ignition switch, etc. It's usually a combination of several things. If you suspect points, it only takes a minute to check them on a side distributor engine. Maybe 2 minutes for a front distributor. You can try popping the front cap and using a mirror to get a look, but I'm going to just pull the front distributor and take it to my workbench. If I'm working on a side distributor, I go get something to sit on.

You should have an ignition point file in your tool box, on the tractor. This is a small metal file that is easy to slip between the points. If they look nasty, just running the file through them is often enough to get a tractor started. Mark it on your list to properly service the distributor as soon as you can.

The point gap for a front distributor is 0.015" and 0.025" for a side distributor. After setting a million sets of points, I can tell just by looking at them if they are close enough to run. I still use a feeler gauge to verify the correct setting. A feeler gauge is another tool that should live in the tool box on the tractor. The wire type are usually easier to use, but a flat type can be just as accurate.

When checking the points, grab the end of the distributor shaft and see if there is any side play. These engines are 50 to 70 years old. It might have been a LONG time since the last distributor rebuild. New distributor bushings only cost around $10 each and most anyone can replace bushings. If the shaft is badly worn you might need a new one. That's a little more expensive. If rebuilding is beyond your ability, rebuilt or new distributors are available. A sloppy distributor shaft is nothing but trouble. It needs to be fixed as soon as possible. I have posted photos of a complete side distributor rebuild further down this page.

FRONT DISTRIBUTOR

All Ford-Ferguson 9N, 2N, and Early Ford 8N

For the Late 8N Side Distributor Click Here

I feel that the front mount distributor on the 9N, 2N and early 8N tractors has gotten some bad publicity that is not entirely deserved. Many people have commented on how much easier the side distributor is to work on. I did not find the front distributor to be a service problem. Remove two bolts, and it comes right off. The front distributor is driven directly off the front of the camshaft by an offset tang. Once you have the distributor in your hand, it can be taken to the workbench to replace points and check the timing.

I believe most of the bad publicity is caused by folks who are afraid to remove the distributor and attempt to service it in-place. Yikes! That is not impossible but is definitely doing it the hard way!

Unless someone has fiddled with the timing adjustment, and the tractor was running ok, the timing is probably ok right where it is. No need to fool with that if you are just replacing points. Once set the timing should not change, but then again, we seem to be having issues with low quality replacement parts. Depending on where you live, and your buying habits, some people have run into parts that simply do not fit right. If your new points are not made and set up EXACTLY the same as the ones you are replacing, your timing could change slightly. There are stories where people have actually had to enlarge holes or drill new ones to get a new set of points to fit! My solution to that is to buy the highest quality replacement parts I can find. I return or throw away parts that do not fit right because I figure the time inferior parts will cost me just ain't worth trying to use them.

While you have the distributor on the bench, its easy to check and reset the timing adjustment if necessary.

Typical Step-By-Step Front Mount Distributor Service

Remove Coil wire, Coil, and distributor cap.

Take note of the direction the rotor button is pointing. This is the direction it needs to point when the distributor goes back on. It will not go on any other way. Even if you forget you can hold the distributor to the front of the engine and turn the rotor until it drops into place. I think it is a little easier to know where the rotor should be.

Remove 2 bolts and take the distributor off. Take a look at the back side. You will see the offset tang that engages on the camshaft. One side of the shaft is noticeably wider than the other. This tang will only fit on the camshaft one way.

Take the distributor where you can work on it. Install a new set of points and condenser. Set the point gap to .015, then place a straight edge on the wide side of the tang on shaft as shown in the attached photo. Rotate the distributor shaft in the normal direction until the straight edge is 1/4" away from the outside edge of the distributor mounting hole. The distributor points should just be starting to open. If not, loosen the timing plate lock screw and turn to advance or retard the timing. Keep adjusting until you get the proper 1/4" setting with the points just starting to open.

This photo shows how to measure the 1/4" timing adjustment.

It is best to be turning the distributor shaft in the correct direction to the 1/4" measurement. This will remove any slop in the advance parts. The 1/4" setting will get your sparks firing at top dead center. That is correct for these engines.
When mounting the distributor back onto engine, 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 without forcing it. If the tang is off, the distributor will not fit flush to the front of the engine and if you try and force it by tightening down the mounting bolts, the casting on the distributor will break. It is not real hard to get things lined up right, but it is easier if you remember about which way it was pointed when you took it off.
My 48 was very sensitive to timing and it had to be very close to dead-on Top Dead Center for it to start easily and run right. When doing final tweaking to get it just right for your tractor you can make slight adjustments to timing without removing the distributor. Loosten the timing lock screw, shift the timing about half a mark, tighten the bolt and test it. Remember which way you turned it because you may want to put it back or try going in the opposite direction.

This simple trial and error approach, making small adjustments one at a time and then testing the results, has always seemed to be the best way to find that perfect final adjustments. No two engines are exactly the same and factory settings can always be tweaked slightly for better performance. The key is to keep track of each change so you can undo the change if there was no improvement or things got worse.

SIDE DISTRIBUTOR

Late Ford 8N (50-52 Only)

The "side mount" or "angle mount" tractor engine blocks should all have a timing hole on the right side near the back where the clutch/flywheel are located. It is covered by a teardrop shaped metal plate with one screw in the small end. It may be cleverly concealed under a thick layer of grease and dirt that can be nearly as hard as concrete. The timing marks are stamped on the flywheel. There are no timing marks anywhere around the front of the engine. That is true for the TRACTOR engine. However, some of the engines found in tractors are not tractor engines. This same basic engine was used in trucks, stationary applications like pumps, generators, and a bunch of other vehicles and equipment. It was a very popular and inexpensive design. Almost anything goes if you cannot read the serial number. Tractor serial numbers for 8N engines always started with the 8N designation. I might use a timing light to see how close my 1952 8N engine is to factory settings, but I prefer to set my final timing by trial and error the same way I dial in a front distributor engine that has no provision for a timing light. If the engine runs at all, mark where the distributor is, loosen the clamp, turn it about 1/8" and tighten the clamp. See if it starts and runs better. If so, try another 1/8" in the same direction. Likewise, if it gets worse, turn the distributor the other way. When you get close, try just 1/16" each way. You can fairly quickly dial in the sweet spot for your engine in this manner. Too much advance will start getting hard to start and will run hotter. Too much retarded and power will quickly drop off. You probably don't have a temp gauge, but keep an eye on the exhaust manifold. It should come close to red, maybe a dull red with a good load on the engine for a few minutes. Glowing cherry red is too hot. Either too much advance too lean on the fuel mixture, or both.

SIDE DISTRIBUTOR REBUILD

This is what they look like off the tractor. Before you get this far, you should have turned the engine to Top Dead Center on the No.1 cylinder, and then lined up the timing mark on the flywheel with the pointer. Then mark No.1 plug wire on the cap. The cap is marked for No.1, but I've seen many distributors that were stuck in wrong and the wires moved to different holes. Save yourself some aggravation and find out now if that is the case. I'm going to thoroughly clean and service this distributor.

Remove the cap and the first thing I see is a damaged dust cover. That big black hole right above my hand shouldn't be there. Put that on the list of parts I'm going to need. The rotor button looks brand new. I'll probably re-use that. Notice the insulator pass-through bushing on the right side in this photo. This one appears to be in good shape. I've seen cases where the bushing was gone, and the coil wire was connected directly to the points. That will certainly work, but unless this hole is sealed, the distributor can collect an incredible amount of dirt.

The coil wire on this one was cut. That's a common practice for used parts. No problem, wasn't planning to use that anyway. Notice the gear drive on the end of the shaft. If it looks worn, plan on replacing that. There is a bushing a little further up the shaft. The gear and bushing are held in place with rivets. Both must be removed if you need to remove the shaft from the housing. This one is so dirty, I was planning to take it completely apart anyway.

Pull off the rotor and dust cover to get at the points and condenser. I was not happy to see all the rust inside this one. Now is a good time to grab the top of the distributor shaft, set the points on a lobe (open), then attempt to move the shaft side-to side, while watching the point gap. Basically, any slop equals your margin-of-error when setting the points. This one definitely needs a new bushing. I've also spotted another problem. The pass-thru coil wire connects to the points with a flat piece of copper. This one is clearly broken.

The top plate is easy to remove. Remove the points and condenser, then remove two screws and carefully pry the plate out. If it's rusty like this one, you may want to soak it in ATF or toss it in an electrolysis tank for a couple of hours. Once the top plate is out, it's time to go after those rivets on the drive gear and bushing. They are brass, so I simply peeled the head off with a sharp chisel and drove them out. You could use a center punch and drill bit to take the head off. Just left of the condenser in this photo is the broken piece of copper that should have been connecting the coil wire stud to the points. You could buy one for about $4, but I will make a new one from scrap copper sheet. You could also use a short piece of wire or pass the coil wire directly into the points. Whatever you do, make sure it only touches the points. If there is any electrical contact for this link between the coil and the points, the tractor will not start.

Ok, rivets are out and here are all the parts arranged how they came off. This is an excellent photo to keep handy when it's time to put this back together. One photo can answer lots of questions. The advance weights on this one are in excellent shape, but that shaft looks bad. Hopefuly it will clean up ok, a new shaft assembly runs about $45. I'll try to clean and re-use this one. The bushing is pressed into the housing and accessible, once the shaft and advance mechanism is out. The easiest way to remove the old bushing is to run a tap in it, thread in a bolt, and then knock the bolt out from the bottom with a punch.

These are the same parts after a thorough cleaning. The rusty parts spent about 4 hours in my electrolysis tank. that took care of the rust. If you want to know how electrolysis works go HERE. The distributor shaft cleaned up OK. It's not great, but this isn't an indy racer either. I now have a complete list of replacement parts needed. I may decide to powder-coat the distributor housing if I can't shine it any better than this. There is a nameplate tag on one side of the housing. It's held on with a couple small rivets. This can be removed and replaced if you are going all-out with a restoration. Once I'm happy with the appearance, these parts will be set aside until I have everything needed to put it back together.

That is why I take pictures. It might be a month before I come back to this project.

UPDATE - 3 Weeks Later

This is the new copper strip I cut from a piece of scrap copper.

It's easier to drill holes in thin material like this if you sandwich the material between two pieces of wood. Drill the holes before you cut to the final shape and you won't have to do as much measuring to get them centered.

The following photo is the new dust cover held next to the original.

There were two different dust covers listed on the web site. When the part didn't fit I went to see if I ordered the wrong one. Now the same site only lists one dust cover for all years. This one is wrong. The original fit down inside the distributor, so the tang on the distributor cap could engage the slot on the housing. This one will fit on the housing, but there is nothing to keep it from turning, and it jacks the cap out where the slot in the cap will only engage the slot in this dust cover. This means it would be relying only on the clamps to locate the cap and it's going to take most of the tension off the spring terminal on the rotor. All I can do at this point is re-use the old dust cover or leave it out.

Here is the completed distributor. The green insulator for the coil wire is a new one I made from a scrap plastic dowel that happened to be the correct diameter. The old one was cracked.