Spud- You don;t have to remove the dist. Use hese steps though for a thorough tune-up 1) Remove spark plugs and check gap/plug condition. Gap s/b about .026". Now, almost everyone posting here on the subject (me too) report better engine performance using a "hotter" spark plug such as Autolite 437s. I don't know the other brand equivalents but they are available in the Archives section. Consider replacing your plugs with hotter plugs. 2) Check your plug wires, BUT mark each wire AND the cap to ensure you get them back on in correct firing order (which is 1-2-4-3 counterclockwise). If they are standard off the shelf automotive resistance wires they are carbon based wires and are not as goodas the copper core strand wires that are spec to this tractor. Resistance wires denegrate your spark. Can get these from a variety of sources such as New Holland, this site etc. You have to assemble them yourself and if you need help, let us know. 3) Check the dist cap. Notice the leads on each cylinder in the cap. If they are burned OR burned to one side of the leads, tis will denegrade spark as well. If more than half of the leads are NOT burned, then the rotor isn't distributing good spark to the cap. This could be a base timing problem, BUT for now just make a note and we'll address it later if your tune-up doesn't work well. Take a tiny screwdriver and flake off the burned part of the leads. Inspect the cap for cracks too. Replace if cracks or if leads are so burned that you can visibly see th lead isn't "flat" withrespect to the rotor. 4) Inspect rotor lead AND spring. Me and others have experienced that the spring may develop a hairline crack where it is attched to the brass rotor lead. If so, replace rotor. Otherwise, take a screwdriver or LIGHT sandpaper and clean the rotor end. 5) Remove points dust cover and take a genral look around to check for oil/dirt/pieces of parts etc. Clean out junk with cloth/ear swab. 6) Grab the dist shaft and rock it back and forth and up and down. If back and forth play is more than 1/16th" or up and down is more than 1/8th" just make a note for now. It indicates worn dist shaft bushings which may cause erratic spark. 7) You have three components on your points: points, condensor, and a 3/4" x 1/8th" irregularly shaped copper ground strip. First remove the nut holding the condensor wire, ground and coil lead wire to the points. NOTE the order of each wire/ground. Remove the two points hold down screws CAREFUL NOT TO DROP one down into the distributor. Inspect the screw threads. Not uncommon for these to be so worn that they have a hard time keeping points locked into proper gap. If worn, get new ones at hardware store BUT NO LONGER than the old screws. If onger, they will interfere with your mechanical spark advance mechanism below the point plate. 8) You can file the points or simply replace them. If file, AMKEsure your end product results in the two points seating all the wat around (i.e., flat) for good contact. I replace mine once per year and file them in the interim. Go ahead and replace the condensor as I can't tell you how to test one. 9) Install points but leaving the two set screws a little loose. Reattach wires/ground to points lead. 10) Engine switch OFF, tranny in neutral, manually rotate the engine using a scredriver placed in the hand crank receiver at front of engine. It turns clockwise as you face the engine. Rotate engine until the plastic rubbing block ofthe points is contacting the exact middle of any of the four "lobes" or high spots of the dist shaft. Using your feeler gauge, adjust the gap of the points until you feel a very - and I mean very - SLIGHT drag on the feeler gause as you withdraw it from the points. Make sure you aren't twisting or cocking the feeler as you do this or you end up with a too wide gap. When you have .024"-.025" gap, gently tighten the points set screws and recheck gap. Quite common for gap to slip when you tighten the screws. If so, try again (and again) until the final gap is correct. 11) Reinstall dust cap, rotor, dist cap, plug wires etc. and give her a try!
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