Hey Guys , when reinstalling your distributor what is the correct procedure again ? Also the firing order for the spark plug wires ? Thanks
18436572 Position the rotor rite b4 or rite at the no1 wire stock position had the the no1 pointed towards the front of car rite b4 the window in the cap
The rotor turns clockwise. #1 is the distributor tower just clockwise of the point adjustment window, then follow the firing order clockwise around the cap, 1-8-4-3-6-5-7-2. Make sure the #1 cylinder is on the compression stroke and not on the exhaust stroke. Don’t make the common mistake of just lining up the marks without checking. As far as lining up the #1 cylinder at TDC compression, it helps to understand the mechanics. It takes 2 complete revolutions of the crankshaft to fire and exhaust all 8 cylinders. Our engines are 4 stroke engines. Intake-Compression-Power-Exhaust. You need to be on the compression stroke. If you split the firing order in half, 1-8-4-3, 6-5-7-2, 1- 6,.....8-5,.....4-7,..... 3- 2 are companion cylinders. When one is on compression, the other is on exhaust, and visa-versa. So when 1 is on compression, 6 is on exhaust, and when 6 is on compression, 1 is on exhaust. See why just lining up the HB and timing tab might not work? These are my tips. DON'T crank the engine, bump the starter a LITTLE at a time. Find a cork to stuff in the #1 plug hole or use a second person with their thumb covering the plug spark hole. BUMP the starter. The instant the cork pops out, STOP. Turn the crank the rest of the way CLOCKWISE with a breaker bar and socket. The Harmonic Balancer mark should be coming around from under the water pump. Line the mark up with your intended initial timing on the tab, I suggest 10*. Once you do that, hold the distributor so that the vacuum advance is properly oriented and rotor is pointed at #1 tower. Now lift the distributor up and eyeball the the oil pump tab to see it's orientation. Take a long screwdriver and orient the oil pump drive shaft to match. Now this is important. The distributor drive gear is helical. That means the the shaft will turn as you push the distributor home. You need to account for this, so you need to note which way it turns and start with the rotor in a position so that as it turns, it ends up pointing at #1. It may take you a few tries. Keep trying until it drops in, DO NOT crank the engine to get it to seat, that will only make things worse. This is normally difficult if you have never done it before. It may help to move the advance weights to get the oil pump to engage correctly. Good luck. Once you install the distributor, and BEFORE you start the engine, tighten the hold down so that you can just turn the distributor with some effort. If you don't tighten the hold down, the distributor can pop up enough to disengage from the oil pump yet still allow the engine to run, with no oil pressure.
Doesn't matter, #1 can be anywhere as long as you follow the firing order CW around the cap and you position the rotor as I described.
Entirely true... ...but it looks amateurish, and it's likely going to cost you to "fix" if you ever take the car to a professional--who will assume that the plug wires are incorrectly installed by someone who didn't know what they were doing. You could potentially run into the problem of having some spark plug wires not long enough to reach the "alternative" position on the cap; and from there you get plug wires routed incorrectly. #5 and #7 are particularly sensitive to plug-wire routing; any inductive cross-fire ignites #7 90 degrees early leading to expensive repairs.
Agreed, and if I was the OP, I would try to approximate the OE #1 position on the Mallory cap, easy enough to do if you are starting from scratch and need to install the distributor in the engine.
Good info - I would like to see the "correct" plug wire length by cylinder with the distributor in the OEM position. Every supposed BBB pre-made wire set I have bought needed adjustments. Is this info in any manual?
Wire routing will be in the Service manual. Wire LENGTH may be. It would likely be in the Parts manual.
Can someone please explain to me this? "#5 and #7 are particularly sensitive to plug-wire routing; any inductive cross-fire ignites #7 90 degrees early leading to expensive repairs." I just replaced my plugs and wires for the first time in 12 years on my GS. It has always run phenomenal but recently started sputtering/chugging until hot and then it subsided. I figured it was time to replace the plugs and wires anyway so I did and it solved the problem. #5 looked the worst and the most different from all the others. Instead of being a little dirty and dry it was a little chalky.ashy looking and appeared to maybe even have erosion on the electrode. Presumably, once it got hot enough, it fired more regularly is all I can think of as to why it seemed to go away after driving a little while.
If I understand it correctly (big if), it's because with the stock 1-8-4-3-6-5-7-2 firing order, if the 7 wire gets spark early from the 5 wire, then the 7 cylinder will fire when the 7 piston is in the middle of the compression stroke; this detonation could cause catastrophic engine failure. If the 5 wire got 7's spark, while not ideal, the damage should be less severe because the 5 cylinder would be on the exhaust stroke. I'm not sure what the damage would even be...I'm stuck on shooting flames out the exhaust. On a cam with a 4/7 swap (1-8-7-3-6-5-4-2), the concern would shift to the wire routing for cylinders 4 & 2.
