[MattKomel]

This is my first time posting, and also my first time really learning about timing.

My problem is that I am getting no spark at the plugs, I grounded cylinder No. 1 plug, and cylinder No. 2 to multiple different grounds while cranking the motor and I'm getting no spark from either. I'll explain what I've done to the motor in case I may have missed something through the steps.

I changed out my intake manifold to a Edelbrock Performer 289, and married it with a 600 cfm 4-barrel carburetor. I took out the distributor so that I could lift off my old intake manifold without getting chunks of gasket and corrosion into my intake valley. I was weary of doing this because I've never set timing before, and never reset a distributor or installed a new one. Of course, I only had a carpenters pencil to mark the distributor, and my marks somehow smudged off.

So first, I found Top Dead Center, (marked TC on the 72 302 5.0 harmonic balancer) made sure I was on the compresion stroke by taking the spark plug out of cylinder 1 and putting my thumb over the hole, felling for the "whosh" of air. I then manually rotated the crankcase 2 notches before TC which should be 6 degrees BTC (before top center), which is what my specifications tell me is accurate for the 302 V8. After setting the initial timing I dropped the distributor in. With the pointer on the distributor pointed towards cylinder one firing point. Cranked it...no spark. Turned over fine, but has a clunking--almost ticking--but closer to a clunk noise with each stroke.

I rechecked the firing order on the distributor. There are two different diagrams that I have seen across the internet, one I think is for Ford trucks (with firing point No. 1 towards the firewall) mine has firing point no. 1 clostest to the thermostat. I went with the diagram on the Edelbrock manifold instructions sheet:

On pg. 3

http://www.edelbrock.com/automotive_new/misc/tech_center/install/2000/2121.pdf

Later, with the distributor cap off, and now having a remote starter, I felt that whoosh of air from Cylinder 1 everytime the pointer of the distributor pointed towards the point closest to the thermostat (as shown in the Edelbrock diagram) so that confirmed that my points were set up right on my distributor cap. I then put a voltimeter on my main spark wire coming off of my coil, and going to my distributor, and I have power there, I put the meter at my spark plug wire #1 (coming from dist. Cap and plugs Onto the spark plug- and I have 13.8 volts at the end of the wire (at the plug) - but I grounded out plugs 1 and 2 (which look fine) and have no spark on either when I crank, and I still have the clunking. I gapped my distributor break point ignition (the little contact point that mechanically tells each point to fire) to .017 which I've read is accurate for all V8s? I did only use a feeler gauge rather than a dwell meter. And I never checked the spark at that point. Finally I replaced the stock distributor with an MSD "ready-to-run" and an MSD blaster coil 2, I had to rewire a balast into the blaster coil/distributor circuit. I then custom crimped my plug wires to fit the new distributor, and still no spark. I am getting new plug wires in tomorrow, and am going to change out the spark plugs just to eliminate a variable. The only other thing I can think of is the Ignition control module, but that is built into my new distributor. I cannot think of any reason why I am not getting spark, and I am worried about the unknown clunking everytime I turn the motor over. Any help would be great! I am at a total loss here. Thanks!

 

[Klinkin]

Make sure your ground strap to your block is good, if you take your ohmmeter and check from your block to your frame to your negative battery terminal you should have very low resistance at any measurement point.

After getting TDC on compression stroke for cylinder 1 you can aim the rotor any direction you want as long as it pointing at the piston #1 plug wire, then install your plug wires CCW in the proper firing order.

When in doubt, pull all the parts you installed off and start your installation over again, you might of skipped a step without realizing it.


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[MattKomel]

Thanks Klinkin. I'll check that tomorrow. I'm guessing around .3 or so ohms would indicate a good ground? I'm putting the Ignition control module in tomorrow, along with new spark plug wires and plugs. Other than that, I can't think of anything else except going through the whole wiring harness to see if it is shorting somewhere. I did actually pull the main spark wire off my distributor and check for spark there--and nothing. Then checked for spark between the coil and the wire, no spark there either. But I read voltage all the way to the ends of my wires, just can't make heads or tails of it. Still suspecting ICM, it's just strange because I never touched it throughout my project.

 

[Klinkin]

Anything below 1-3 ohms is good. Above that you might have paint or corrosion somewhere in your connection.

Are you using a spark plug to test for spark? Your not going to see it with a volt meter, make sure the connections is good, and ground the threads to the frame, hold the spark plug with a insulated pliers and bump the motor to see if u have spark.

It is possible to get a bad coil out of the box, don't discount a part being bad, just cause it is new out of the box. Mine was the the first time.


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[MattKomel]

Okay, I have spark now. I had a faulty ground on my ignition box. I set the timing yesterday to about 8* advanced with a total timing of about 36* I've heard that 34 is about the highest you want to advance your timing on a 302, but I'm going to play around with it a bit, and maybe change out the springs and bushings on my MSD distributor. I am still having poor throttle response though. Or more accurately, the motor bogs down when I really step on it, mostly in first gear as well. My car did this before I did anything to it. But it would only do it when the engine was cold, or hot (driving on the highway, coming to a stop sign, then trying to go again---I would have to feather the pedal to keep from stalling out.) Previously, before the mods, It seemed to get worse on humid/rainy/cooler days and nights. So I re-tuned my old Carburetor, which seemed to help a bit, then It came back with a vengeance. Now that I have the new Carb and intake on, it only does it when I really step on it.

It's a 600cfm Edelbrock on a 302 5.0L. I am hoping I didn't over- carbureate my motor. My first suspect would be the fuel pump as it had a similar problem with the old carb. Im going to change that out later this week, along with changing out the hardline fuel line.

My second suspected culprit are the metering jets being too large, and bogging down the motor by created too fuel rich air for combustion when the pedal is mashed to the floor. Still tweaking with her.

I've heard about having poor throttle response and weak power under a load due to the throttle linkage on the carb itself. Someone told me to bend the small rod on the carb, reducing the amount of slack, and also traveling distance of the throttle... I think it's a fuel issue though.

 

[Klinkin]

I'm having a bog issue also, did many of the same things u have. I was told our sbf like to be lean, the only thing I have yet to do is lean out the jets. I'll be watching this thread if u figure it out.


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