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Working on doing a basic tune-up on the '77. I don't want to say how long since it's been done, a LONG time. Car is pretty much OEM or replacement OEM including the engine, nothing fancy. Got the cap and rotor off and here's what I'm looking at.
I know just about enough to replace the basic parts I'm working with but not much more. I do recognize weights and springs, etc., but not sure if I should be concerned with the condition of the parts I've exposed. Am I OK with just leaving this alone? Clean it up a bit and let it go? Start replacing parts? Which ones? As always, appreciate any help and input I can get.
Looks like surface rust. Disassemble, clean, very light coat of oil and reassemble.
I'll give it a try. On closer inspection it looks like most of what looks like rust is just a fine reddish colored dust coating. Found the same powdery coating underneath the rotor. Can you give me an idea of what can be disassembled without removing the entire distributor assembly? Looks like just the two springs and weights? Maybe hose the whole area down with carb cleaner or electrical contact cleaner then a light oil?
Put a hand vacuum pump on the vacuum advance to determine if it works. Check the curve with a timing light. Read the technical paper written by Lars and SWCDuke for mapping the curve with springs etc. Jerry
Looks like it has been in a damp area. . I would use CRC electrical contact cleaner, then Q tip . If it runs okay leave it ! The only item i would have replaced is the module. This has to sit on a base of dielectric lubricant. This is an item over looked but it is electrical and moisture does not improve its function. I would get a spare at rock auto i believe they have the original replacement, for i have bought one for replacement , I believe standard ignition is the manufacture. You can test it with a multimeter after you purchase it on the ohm scale.I would not accept no other manufacture.
Fake, is on the right track, but I think he means Heat Sink Compound (thermal barrier) applied under the "modge". Dielectric grease is more for corrosion resistance, waterproofing GOOD electrical connections such as both ends of plugwires, plug terminals, taillight bulbs, trailer-light harness,etc.
If you do use some type of chemical spray to clean the dizzy, I would mount the dizzy up-side-down in a vise, allowing it to drip away from the interior of the unit. You do not want any cleansers running down into the housings bearing.
I agree with others, pitch the springs, clean the weights. Note the orientation of the weights when disassembling / reassembling. If you install them on backwards you will be back on this forum with more issues.
New cap / rotor & spring kit, new Modge and you should be good to go. A light coating of White Lithium Grease under the weights will assure proper advance movement.
Checked the vac advance and, although it holds vacuum, I see no movement with 25inhg of vacuum on it. In every failure mode I've seen it would not hold vacuum so I'm wondering what's going on. Looks like I'll have to take it off and check it.
False alarm, the vac advance is fine, vac gauge operator error.
New weight/spring kit and new module on order.
Check the condition of the nylon bushings under the weights:
False alarm, the vac advance is fine, vac gauge operator error.
New weight/spring kit and new module on order.
Check the condition of the nylon bushings under the weights:
Standard and NAPA has those nylon bushings.
Just pull it out, dis-assemble and clean, and re assemble.
Rotor tip aligns with the gear dimple.
No lubricants up high. It just causes more issues than good. If you want, oil it with gun oil and wipe completely dry.
Chances are without testing, new springs will jack it up. My 2 centavos.
DO NOT USE aftermarket weights. They all SUCK>
If you can find those plastic/nylon bushings that would be great. I couldn't find them when I rebuilt my distributor. Used some nylon bushings that I found @ Lowes in the hardware section. They fit nice and tight and are similar to what was broken on mine.
If you can find those plastic/nylon bushings that would be great. I couldn't find them when I rebuilt my distributor. Used some nylon bushings that I found @ Lowes in the hardware section. They fit nice and tight and are similar to what was broken on mine.
Different bushings. His are for the weight pins, Yours are the weight rubbing blocks, which are the same as the tach gear thrust button.
Love Lowes. But not for car parts, just home improvement. Look at Summit for IGN parts: cap, rotor, springs, bushings, etc.
You own a desirable sportscar now. Not a time to bubba things up using the corner hardware parts.
And I still say lube under the weights with White Lithium grease. It is an automotive lube. Won't melt, won't fly off. If you don't coat those weights, you will be right back where you started with rust.
Last edited by HeadsU.P.; Dec 11, 2019 at 08:26 PM.
Love Lowes. But not for car parts, just home improvement. Look at Summit for IGN parts: cap, rotor, springs, bushings, etc.
You own a desirable sportscar now. Not a time to bubba things up using the corner hardware parts.
And I still say lube under the weights with White Lithium grease. It is an automotive lube. Won't melt, won't fly off. If you don't coat those weights, you will be right back where you started with rust.
Any oil/grease gets thinner with heat and flings off doing more harm than good.
Point cam grease is even an issue if it's the wrong stuff.
The nylon bushings and pads are the bearings.
Coat the other parts in gun oil, and you won't live long enough to see that again.
If the module is good, leave it alone, and put a spare in the glove box.
Those rub blocks look OK on mine surprisingly. At least I think they're good, don't know what they looked like new so don't know how worn they really are. Strange how they're different colors.
I'll probably hit the rusted parts with a light coat of CL&P after they're cleaned up. If you're a 'gun nut' you know what that is. If it's good enough to run m16s in the desert it'll probably be OK in this environment.
Those rub blocks look OK on mine surprisingly. At least I think they're good, don't know what they looked like new so don't know how worn they really are. Strange how they're different colors.
I'll probably hit the rusted parts with a light coat of CL&P after they're cleaned up. If you're a 'gun nut' you know what that is. If it's good enough to run m16s in the desert it'll probably be OK in this environment.
Those pads are fine for now. They are white nylon that turns brown with heat and time.
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Rusted/dirty Ignition Hardware
