Thread: 350 Spark plug & wire change

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I changed my plugs and wires today and now my car wont crank it was cranking fine before but i new they needed to bechanged.Help me out. I did not gap the plugs but wouldn't it still crank. the last ac delcos i put in i didnt gap those. these are Autolite 685. with accel superstock wires

By not cranking are you saying it won't turn over at all? Does it turn over and not start? Does it start to turn over then stop? Need more info. Not that I think it has anything to do with your problem, but why don't you take a few seconds to gap plugs before you install them?

Oldman2

Probably got the firing order wrong or your coil wire isn't on all of the way. Some coils/wires require a special adapter or "tower".

The car turnsover but wont fire up. Sometimes it seemslike it wants to fire but doesnt. could it be bad wires. i think i'll try putting theold wires on andsee what happens. It should be in the right order i pulled them one at a time. I dont know what the gap should be how do i find out. I'm new to doing this stuff myself but want to learn. This is a rebuilt 74-75 350

I checked the plugs and the plugs are dry. I'm going to gap the plugs and see what happens. would the car not fire if the plugs aren't gapped? It has stock heads with headers and air gap intake and 1.6 comp roller rockers.

Yes i pumped it before i tried to start and all the wires should be in the right place because i took them out and replaced them one at a time. Would the car not fire if the plugs arent gapped?

Question
What type distributor are you running? While changing the wires did you perchance unplug the HEI?? Is it still points?

I dont think its any way the wires could be wrong if i took them off one at a time. The car cranked fine before this. I hear accel wires arent good could they be faulty? Does these autolite 685s have to have the right gap in order to fire? what is the firing order and which side is #1 plug on? I new to this.

#1 plug is left front. Firing order 1-8-4-3-6-5-7-2.

I've only put about 15K miles on this rebuilt engine. What does this mean if The timing chain jumped Denny?

Its a 74-75 350

First of all, you have to start using the right terminology if you are going to give us the correct info so we can help.

You say the engine won't CRANK. That means you turn the key and nothing happens, the engine doesn't turn even one revolution, or.....

The engine won't START. That means you turn the key and the engine spins over but doesn't start running on it's own.


Which one do you have??????


Don

The engine turns but doesn't fire up

Good, now it is clearer what is going on.

So the car ran ok before you did the plugs and wires, is that correct? When you bought the parts what did you tell them so they could pull the correct items?

Even if you pull one wire at a time, it is possible to still screw up the order. I have done it more than once, and I suspect it happens alot. What you will want to do is retrace all of your steps. Someone on here will probably be able to post a wiring diagram for the plug wires. Check yours one by one against that.

Plugs are not pregapped in the box. One plug may fit a whole bunch of applications, so you gap them to the car you are doing. They can also get bumped and close up the gap, so you have to check it. You can even bump it putting them in the hole.

That being said, gaps can be way off and the engine will still run, but maybe not really good, so you have something else going on. Did you pull the cap off the distributor?

You are starting to get us good info, so we might be able to help.


I see Denny was posting while I was typing, great now you have a diagram to follow.

Don

Ok so the #1 plug is on the driver side? No i didn't pull off the distributor. and the car was running fine