whats the best replacement for points ignition

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bowshooter1

New member
Hi I've got a 1972 Scout 2 with the 345 and a 4 speed. I've had the Scout since around febuary and have loved messing with it but just can't get it to stay running.

At first I changed the distributor cap plugs wires and rotor and fuel pump. I could get it to run by putting gas down the carb, then I hooked up a temporary gas tank and got it to run and idle but it wouldn't rev up at all. The scouts at my dads house and at the time I lived with my Mom so I could only work on it on weekends. Well the next weekend that I came back it wouldn't run at all. So I rebuilt the carb, after I rebuilt the carb it would start up but it backfired like crazy and wouldn't idle. I tried every different setting on the carb possible then decided it might be something with the timing, so I spent the next few nights soaking and prying on the distributor until I finally got it to break loose. I got it timed to where it will backfire less but its still a lot of backfiring, no idle, and no much power.

Last time I went to my dads and tried to get it to run it wouldn't start at all, even when I put a little gas down the carb.


I'm almost positive it has something to do with the ignition and wanted your opinion on which to get. I've heard petronix are good but I've also read you could make a GM hey distributor work with a Jeep distributor gear and since I like making stuff myself id rather something like that.

Sorry for typing so much I just wanted to let you know what I've already done so you might have a better understanding of what might be wrong with my Scout
 
Welcome bowshooter, sorry for your troubles but we have all been there.
My best advice is to determine just what is wrong 1st before you throw money at it.
The truck will run fine on a points dizzy, are you timing off of #8 cylinder?
If you read the post on power timing in this sub forum it will get your timing set right.
If it still does not run then we need pics (detailed) of your carb so we can help you further.
The more detailed pics the better.
But if it were me I would try to get your current dizzy set right before I upgrade, there is not much to trouble shoot with points, set gap, and make sure #8 is top dead center, and one last thing check your plug wires for firing order. I have made a firing order mistakes many times and swore I had it right the first time. So check firing order, then check it again, then again!! Countless people have swapped plug wires and switch a plug wire around.

Keep us updated with your progress.
Ron
 
Thanks for the reply, I don't have a timing light so I'm just timing it by ear to the point of where it backfires the least. I haven't checked since the last time that I was up there to see if I have fire at the plugs so that will be the first thing I check when I get back. But since the points have not been replaced yet do you think that the points could be causing the backfiring?

If I take the cap and rotor off and look at the points I can see a bright blue spark in between them while turning over the engine


and to answer your question I have read the power timing thread and I think that will be very useful when I get to the point of actually getting it to run good enough to time
 
As far as the points go you can just sand them down with emery cloth and then set the gap. (about .018 gap) just to get it to run.
I would pull the #8 plug and stick a little tissue paper in the plug hole, turn the engine over and when the paper puffs out stop and check your timing Mark (doing this with the starter it is easy to crack it to far). The best way is to pull all the plugs and turn the crank with a wrench, much more control. When you find tdc of #8 your timing Mark should be at tdc or advanced about 5 degrees.
Once that checks out pop the dizzy cap and see where the rotor is pointing, it should point to the # 8 plug wire.
The firing order is stamped on the manifold follow that to check the plug wires/firing order.

With the backfiring you described, I still suspect the firing order.

Ron
 
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Ok thanks I tried that same thing but I did it to the #1 spark plug.

Firing order is 18436572 right? If so I've got it right unless I pulled a wire and accidentally put it on the wrong plug.

Im not anywhere near the Scout right now but I will have my Dad go check the firing order and set the timing as you described and let you know how that works out.
 
Your firing order looks right, you have to have that # 8 wire right or it screws everthing up. It sounds like you found the back fire issue, tdc of #8 cylinder= a timing Mark on the crank= the rotor on # 8 plug wire, then follow the firing order. So the plug wire after # 8 is the #4 plug and right on around the cap, #1 would be the last on tho put on if you follow the rotation of the rotor.

Good luck
ron
 
Thanks hopefully that should fix my problem.

And I don't mean to be a nuisance asking a lot of questions, and to tell you the truth I should have asked this earlier as it May also be part of my problem but when I first got the Scout it would only run while I had the starter turning over but I had an old shade tree mechanic tell me to hook up a wire straight from the hot on the battery to positive on the coil and it works, I've had it running lime this before all my other problems but id like to fix it the right way. How do I fix that?
 
The type of direct bypass you describe is mainly for troubleshooting or emergency situations and not meant to be a long term fix as it supplies full battery voltage to the coil constantly. This hard on the coil and the points, especially when the engine isn't running. Originally, there were two wires connected to the + terminal of your coil. One originates from the starter solenoid and the other was/is a funky looking cloth insulated wire. The wire from the starter solenoid is your bypass feed which provides full voltage to the coil only during starter cranking. The insulated wire is a resistor wire which supplies a reduced or ballasted feed to the coil from the ignition switch when the key switch is in the "on" position. The lowered voltage via a fairly precise resistance factor of roughly 3.2 ohms is necessary with a breaker points ignition to prolong both the life of the coil and the points. What often happens is that insulated resistor wire overheats and breaks contact, or some "all knowing" moronic po removes it in favor of a standard automotive wire, not realizing that a constant full voltage feed to the coil is a no-no. If the original resistor wire is missing or damaged beyond the point of being useful, you can eliminate it complete and run a 14-16 gauge wire. This new wire will need to be interrupted at some point (firewall) by a porcelain ballast resistor with a resistance factor of roughly 3.2 ohm. Without proper resistance to the coil in one fashion or the other, the engine will never run properly, and you will burn out your coil and your points in short order.
 
Ok so since theres no insulated wire I run the 14 gauge wire from the positive terminal on the coil to one side of the ballast resistor then have another 14 gauge wire connected to the other side of the ballast resistor, but where does the other end go?

It can't just connect straight to the battery can it?
Is there a wire coming off the ignition switch that this would go to so that it only powers the coil when the switch is on?
 
Yes there is a wire from the ignition switch that is hot while the key is in the run position that will go to your ballast resistor. So when you turn the key off the motor will shut off, it doesn't now with your bypass in (if you can keep it running that is)
there is a connector called the bulkhead connector it is where your dash wiring enters the engine compartment (known to have bad connections over time) it is located on the pass. Side to the left of the hood latch on the firewall.

Ron
 
Ok thanks ill look for the bulkhead connector and test wires and see which wire has power when the key is on but no power when the key is off.

Thanks for your help ill let you know if this fixes my problem when I get a chance to go work on it.
 
Some pretty good relaying of the baton here between me and ron. Hey, that rhymes! Now, the one point where I May have lead you astray, but not necessarily, is where I mentioned the resistance value for the ballast resistor you need to get. This presents another learning opportunity for you. I stated that value under the assumption that your coil is the original or a standard replacement, but we don't know that it is for sure. Just in case some aftermarket, performance coil has been installed with an as yet undetermined resistance value, you need to test the primary resistance of your coil before you purchase a ballast resistor. Its really easy to do. If you don't know how, sound off and I'll walk you through the process.
 
There are a few threads where various causes of backfire have been discussed. Here Is a good one. Could be you have one of many possible issues with your valves in combination with any fuel/ignition issues.

Good luck
 
I have a stock coil but I need a new one too since last time I was trying to get it running the coil started smoking but I think thats because I need a resistor, so I'm going to get a new one but nothing special.


And as for back firing, it started as backfiring out of the carb but I messed with the timing a little and now it back fires out the tailpipe (enough to where it blew the pipe off the end of my muffler) when I can get it to start up and stay running it backfires constantly. I took off the valve covers and watched all the valves moving and they all seemed to move the same amount so I think all the valve springs and the cam are fine
 
Yeah, all you need is a stock replacement coil with the points ignition. No real benefit to be realized from some fancy smoke blow in a can mega volt thrower at this point. So, that 3.2 ohm resistance figure I mentioned earlier is actually the total we want to shoot for. Pretty much any coil will have a certain amount of measurable primary resistance, even the ones that have the words: "use only with external resistor" printed on the can. So we want to determine what the value is for the coil you will be using and subtract that x.x figure from the 3.2 target. The remainder is the amount of resistance we will need to get from the ballast resistor. Any combined total between 3.0 to 3.4 ohm will be fine, with the middle of that range being perfect.
 
You still need to be sure of the timing! You said you set the timing or firing order off of #1 cylinder it has to be #8, nothing will fire right untill you are positive of the firing order. Yes, if you smoked the coil you should replace it. It smoked due to the full voltage you were applying with your bypass wire (no ballast resistor). Stock coils don't like a full 12vdc.
You need to tackle this one step at a time, when your are sure of the firing order then you can look at something else as the cause.
Ron
 
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