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Replacing spark plugs and wires

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Replacing spark plugs and wires
A

AZ75CJ5

Jeeper
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Location
Phoenix, AZ
Vehicle(s)
1975 CJ5
Is there any reccomendations/suggestion that you all can give me regarding plugs and wires. I don't know if there actually anything wrong with the ones I have, was just thinking about changing them out so that I know they are new and the condition they are in. Should I save the money and wait until I know they are bad? Or is replacing them still a good idea? Thoughts???
 
If you are not sure how old your wires are, it would be a good idea to replace them. Autolite plugs seem to work the best for the ignition system in the CJ. MSD makes the best wires but are quite expensive. If you still have the oem ignition swapping out for a Motorcraft or HEI would be a good bet.
 
AZ75CJ5 said:
I don't know if there actually anything wrong with the ones I have,
Click to expand...

Let's find out, do you have an ohms meter? If not you can pick one up on the cheap anywhere from free (harbor freight with coupon) and up.
Visually inspect the wires for cracks and corrosion.
If all looks good test each wire by attaching the probes of your ohms meter to each end of the wire. Typically they should run 8,000 to 10,000 ohms per ft.
If they check within range take the money you would have spent on wires and purchase some tools or beer.
 
Posi said:
Let's find out, do you have an ohms meter? If not you can pick one up on the cheap anywhere from free (harbor freight with coupon) and up.
Visually inspect the wires for cracks and corrosion.
If all looks good test each wire by attaching the probes of your ohms meter to each end of the wire. Typically they should run 8,000 to 10,000 ohms per ft.
If they check within range take the money you would have spent on wires and purchase some tools or beer.
Click to expand...

Haha.. I really like this idea. Can never have too many tools or beer. :chug:

However I have found myself looking all through parts catalog and finding things here and there to upgrade and pretty her up. But before I started beautifying her, want me to be running smooth. Lol..
 
I have used Autolite plugs in my Jeep for almost 30 yrs.
I strongly recommend you apply some copper anti-seize to the plug's threads, and dielectric grease(use a Q-tip)to the inside of the plugs boot, and where the wire it attaches to the dizzy cap. Also put a coating on the top of the rotor contacts. That helps to reduce RFI to the radio.
If your replacing the plugs and wires-Best to get a new dizzy cap an rotor. make sure your new cap has brass contacts and NOT the alum. ones.
LG
 
If you are going to replace one, make sure you replace them all. Replace then one at a time don't take them all out and then put them all back in. Is there a reason you are thinking about replacing them? Is it missing? Is it running rough? At a certain RPM does the whole vehicle jerk? Or are you like me and just like to replace stuff:rolleyes:. However, my husband would say if it isn't broke don't fix it.
 
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About prettying things up. Remember, pretty to a hotrod guy might not be the same as pretty to a jeep guy. A lot of us tend to be all about getting power to the ground, not a necessarily a sparkle in the eye. If I were you I'd spend my Limited time and money getting the important things right. If your jeep is running right now the ignition can't be that bad and it won't keep your jeep from being on the road. A totally out of whack drive line will.
 
IMO-Omix=:dung:.
Go to your nearest NAPA Auto Parts, so you can see what your buy'n and get to know those guys.
LG
 
Posi said:
Visually inspect the wires for cracks and corrosion.
Click to expand...

Disclaimer: I'm just a shadetree mechanic (if even that), so anything I say about anything may be dumb or just plain wrong.

I like to take a piece of wire and use it to ground a screwdriver to the frame, and then pass it along all over the insulation on the sparkplug wires to see if it arcs through anywhere, too. I had an old Plymouth Duster ages ago that the wires looked fine on, but lo and behold the insulation had broke down and it was arcing all sneaky-like and making it run bad. That's the only time the grounded screwdriver ever found anything that wasn't already obvious, but maybe worth fooling with if you've tried a bunch of other stuff and are still scratching your head.
 
I did notice when it was driving that in 3rd gear was rough and seemed to lose power. I know that there is a vacuum leak so not sure how much would have to do with that also.
 
+1 on NAPA. The corporate and franchise stores I've used have always been well staffed with friendly, knowledgeable folk.

The only thing at NAPA which has let down is the parts computer.

If you're replacing a Jeep part, take it into the store with you and make sure all the holes on the old part and new part match.

-Jon
 
Stay away from Omix as suggested.

Stay away from BLACK caps and rotors as they contain carbon and promote early arcing.

Stay away from carbon string (graphite) wires as these BREAK internally easily.

Stay away from solid core (copper) wire unless you don't have a radio.

1. Buy SPIRAL WOUND WIRE in 7, 8, or 10 mm silicone jackets. MSD, MALLORY, BELDEN (NAPA), BOSCH, MOTORCRAFT, ACCEL all have versions.
2. Buy caps with BRASS TERMINALS
3. Keep your fingers and parts clean when installing.
4. Use non-conductive boot grease on the plugs boots.

About once a month...go out in the dark (really dark) and crank your jeep. Let it idle while your eyes get dark adjusted (about 4 minutes eyes closed). Use your peripheral vision to 'see' electric arcing to ground from your plugs, wires, cap, coil, etc. This will help you identify parts that are either 'dirty' or failing. Plugs can be cleaned off, but arcing from boots or across the cap/coil is usually replacement only.
 
You have so many drive train issues it's a wonder it ran at all in 3rd gear. The rear drive shaft will vibrate and do all kinds of odd things at speed. Once you get the differential turned down where it belongs things will deffinately be different.

I like the wire and screw driver suggestion. Running your engine in the dark is common and enlightening, but more or less forcing a short with the wire would be better yet.
 
Posi said:
Visually inspect the wires for cracks and corrosion.
Click to expand...

MrPolecat said:
Disclaimer: I'm just a shadetree mechanic (if even that), so anything I say about anything may be dumb or just plain wrong.

I like to take a piece of wire and use it to ground a screwdriver to the frame, and then pass it along all over the insulation on the sparkplug wires to see if it arcs through anywhere, too. I had an old Plymouth Duster ages ago that the wires looked fine on, but lo and behold the insulation had broke down and it was arcing all sneaky-like and making it run bad. That's the only time the grounded screwdriver ever found anything that wasn't already obvious, but maybe worth fooling with if you've tried a bunch of other stuff and are still scratching your head.
Click to expand...

You may have missed the rest of my post about testing the wires with a ohms meter. Whatever works for you is cool, I use an ohms meter and takes about 20 seconds a wire. The visual check is to see the obvious and to toss them without further testing.

Posi said:
Visually inspect the wires for cracks and corrosion.
If all looks good test each wire by attaching the probes of your ohms meter to each end of the wire. Typically they should run 8,000 to 10,000 ohms per ft.
Click to expand...
:chug:
 
Honestly other than being really rough (terrible job of a thing calked lift) and issues switching gears (no pivot ball, inner spring and bell housing with a huge hole where fork goes in) it fired right up (had to buy new battery), drove good and strong. Can only imagine now after I'm done with these things. Keeping soa and going yj springs and new shackles, perches, body mount.

Reason I brought up plugs and wires is because I hate seeing her just sit there. I just wanna twist some wrenches, get diry, drink some beer listening to music and spend time with her. Haha. But really want her safe and trail ready by time it cools down. I probably sound like a creeper, but I think Im in love. Haha
 
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