Ford Mustang Forums banner

1 - 8 of 8 Posts

·
Registered
Joined
·
417 Posts
Discussion Starter #1
We just got done installing an AFM cam, s/c, and many other goodies on my 94 Cobra and it just won't fire up. It will crank and pop every once and a while, but just won't fire. We checked the spark and that's fine. You can smell the raw fuel after cranking it for a while, so we know it's getting fuel. If I have the distributor off 1 tooth will it fire at all? I'm thinking it's a timing problem...any other ideas?
 

·
Registered
Joined
·
1,042 Posts
Definitely sounds like a timing problem Find TDC again, and stab that distributor back in with the rotor pointing at #1.
 

·
Registered
Joined
·
3,567 Posts
Your ignition is firing on the wrong TDC. Do this: Line up the engine on TDC by the balancer. Mark the location of the rotor. Pull the distributor and rotate the engine over ONE revolution, back to TDC again. Now reinstall the distributor to the marked position. It should fire up then.
 

·
Registered
Joined
·
417 Posts
Discussion Starter #4
Alright, I'll give this a try. I am definitely going to back-track a bit and start by finding TDC and see if the rotor is pointing to #1 on the rotor. Thanks
 

·
Registered
Joined
·
3,567 Posts
stacked8 said:
Alright, I'll give this a try. I am definitely going to back-track a bit and start by finding TDC and see if the rotor is pointing to #1 on the rotor. Thanks
No, you're missing something. The crank turns twice for every 1 cam revolution. Take the cap off and you'll see the rotor points straight back (#1) at TDC, and if you turn it over back to TDC again, the rotor will be pointing straight ahead. Your distributor is 180 degrees (360 crank degrees) out of phase with the cam. You're lighting the plug during overlap, instead of at the end of the compression stroke.
 

·
Registered
Joined
·
1,042 Posts
Billy Edwards said:
You're lighting the plug during overlap, instead of at the end of the compression stroke.
That's the key.....the spark is firing during the exhaust stroke, and not the compression stroke. That's why you do the whole, "finger over the plug-hole" thing, so you know you're on the compression stroke, and THEN you check for TDC, and check where your rotor is pointing.
 

·
Registered
Joined
·
417 Posts
Discussion Starter #7
I was planning on doing the finger over the plug hole method to find TDC, then check to see where the rotor is pointing. My assumption at this point is exactly what you guys are saying. When I initially dropped the distributor in, I set the timing mark to 0 and dropped it in, but obviously I needed to go one more revolution on the crank. I just talked to Rick at AFM and he told me to find TDC for 1, manually crank the motor over until the timing mark is set to the 10 degrees mark, then drop in the distributor. Should I try this, or just drop it in at 0 then adjust the timing later?
 

·
Registered
Joined
·
1,042 Posts
Either way should work. Personally, I always just stick it in with the balancer at TDC, and set the timing later, but it's totally up to you.
 
1 - 8 of 8 Posts
Top