Gregdatech said :Have you checked for play in the distributor shaft? , I was wondering if there should be any play in it? Becuase I am replacing mine ( i think it is whats giveing me problems) and I can move my rotor about 1/2" counter clockwise and cant move it clockwise at all? Is this normal? I wouldnt think it is, and somone told me it was not? Just wanted to ask.... And Bailingwire : Start the truck (if it runs) and start moveing wires arround and checking them, also do what Tourque 1st said and make sure you have a good ground wire connection to the body fron the battery.

 

Dave, spring loaded rotation is normal. That's the mechanical advance. Side to side movement would indicate worn bushings and possible problems with erratic spark.

 

hey thanks for the fast reply, I am afraid, thats not my problem then..... It only moves one way about 1/4 of an inch and it goes right back to the original position (springs back)... I was planing on buying an entirely new (rebuilt) dizzy... but now I am wondering if it is worth it? Cant I just buy a kit and do it myself? Or is it about the same ammount of money? Also What type of coil is a step above the stock coil on my 77 302? And what does the stock coil put out? I was thinking of geting a MSD Blaster 2, it puts out 45.000 volts, it says that is 15,000 more than stock? Is this a good coil to buy? I know MSD is the choice of alot of people? But would it be ok to put on my stock ignition? I would be upgradeing everything except the dizzy later on with MSD anyways..... When I get the cash.?

 

I am trying to find out what is wrong with my 77 302, it is in my 77 F-100 Shortbox and it has started missing, and doesent run well.... I replaced the intake and carb with Power+Plus and Edlbrock Performer 600CFM Carb. I am thinking the problem is my distributor, everything else checks out ok... I have not goten the computer tested, but I am almost positive that is not the problem, I went out and checked the gap between the Armature spokes and the Stator, I noticed in the manual I have that the Stator tooth sticks out very little, on my dizzy it doesent stick out at all... So I grabed my feeler guage and checked the gap, it is .025 or 635mm, it doesent say what the gap should be in my book so I looked all over to see if it could be adjusted, I didnt find anything that looks like it can be adjusted in my distributor. I thenchecked to see if there was any movement that was not normal from the Stator assembly, it moves.... I am thinking that is a bad thing? I would not think that it is a good thing since it says in my repair manual that "Each 1/2 tooth error is equal to 7 3/4 engine degrees timing error. " And I have had trouble with my timing since this started happening, I timed it with a light and it is set at 8.deg. BTDC I was told it should be between 8 and 12. I hope somone can help

 

Make sure you get everything replaced or at least figured out before you start doing the expensive upgrades. A bad ground is a terrible way to lose a $300 igniton system.

 

Oh I know..... I am not spending 300$, untill I get her running in perfect shape... Just wanted to know about the Stock coil output Volts and if MSD Blaster II is a good coil to upgrade to? Also wanted to know about the rebuild kit on the dizzy?

 

RacerDave, I know of no kit to rebuild the DuraSpark distributor. The only wear points on the distributor itself, are the shaft bushings and gear (and the mechanical advance parts). Most people just buy a rebuilt unit.

The DuraSpark coil puts out about 30-35K volts, with a plug gap of .044". You can upgrade to a MSD coil with no problems, and re-gap the plugs to about .050".

 

Not sure on the Dura Spark but my Accel unit sets at .006. You might have worn bearing that allowed the teeth to touch and wear off.

 

but are you sure? I need a positive reply.... Because I want to know if my dizzy is worth replaceing... or not? Or should I replace it anyways? The engine was rebuilt 8000 miles ago and I am not to sure if the distributor was done along with everything else.... But it does have some corosion on the Armature spokes (which I cleaned off, and also the ground screw was caroded with greenish (almost like battery acid corosion), I cleaned it out as best as I could with really really fine sand paper.. I made a point of not takeing off any metal, just took off the (rusty brown stuff), almost like a light rust had formed on everything in there? I am thinking more and more that my dizzy is my problem, but I dont want to replce somthing that is not in need of replacement. Can I take it out and get it tested? If so would it cost me anything or, should I save my time and money and buy a new one ( like I was planing on doing), OR..... Should I get a rebuild kit and do it myself? I am sure what the kit comes with, but I would imagine I would need a new Stator, along with the stuff for the vacuum advance and new Armature spokes, along with the screws and wiring? Do they sell a kit like this? Any help would be great, Thanks in advance.

 

hey thanks that helps alot!

 

Double check your manual to be sure but .006" gap between the reluctor and pickup coil sounds right to me. The adjustment proceedure should be in there also. There should be an adjustment like the points had to set the gap. Loosen one of the screws that hold the pickup coil bracket to the breaker plate and use a flat blade screwdriver in the slot provided to move it. Make sure you measure the gap with a non-magnetic feeler gauge.
And if there's corrosion on the ground wire connection you'll have problems. Make sure that's really clean. You can probably get a little more aggressive with the sandpaper to give the surfaces a little "tooth" for a better connection.
Also, a little surface rust on the reluctor doesn't hurt anything 'cuz there's no physical contact there.
Just my 2¢
Greg

 

Grab hold of the rotor bug and push it sideways back and forth and pull it up and down. Should be a little play but not much side to side. Also look for signs of fine metal dust.

 

The msd blaster is an awesome coil. The autolite 25 spark plugs are already gapped at .050"

 

Ok well I know points are adjustable... but I dont see anything on how to adjust electronic ignition.... I have heard there is no way to adjust it and that you just have to buy a rebuilt dizzy, I am buying an OHM meter to test the resistance of my sparkplug wires and my stator (after I replace my dizzy) to make sure its not my wires... Also buying a Volt meter, I have heard they are very handy... As for the Coil, I was thinking of keepiing the stock setup, and just upgradeing the coil..... I dont really see the point in haveing new MSD ignition installed for over 300$? All I really need is more surface area for the spark (opeining the gap) and a thicker spark (better coil will do both) so.... If I dont want to I dont have to right? I meen if this is going to be a daily driver is it worth the 300? Or should I just go with the Coil for now? (after I fix all of my problems I have now).

 

Racerdave, don't worry much about the gap between the reluctor and pickup it isn't excessively critical as long as the parts don't hit or the reluctor triggers the ign. consistently it's good enought.
I'm not sure how well the DS stands up to a hotter spark but I would imagine the worst case would be slightly more frequent parts replacement.
If your going to buy a meter (especially if it will see a lot of use) buy a good electronic Multi-meter, I'd recommend one with a rubber sheath around it since that helps protect it if dropped and electronic because it's harder to damage those than analog ones.