Hi I'm new here

Just recently bought a 74' f100
302 5.0L v8 rwd
Was running fine until today

Has a new battery
New spark plugs
New oil and filter

So this morning I was messing with the carb and drove it to work . I noticed it was idling smooth but driving rough.
I thought maybe the guy I got it from had the Sparks to dist. Cap set wrong so I followed a diagram I found and after following that I had a backfire through the carb .
Now it won start.

Do I need to take to a mechanic or is this traceable myself ?

 

sounds like an easy one! ensure your firing order is correct 1-5-4-2-6-3-7-8. timing around 10* btdc. is it a 5.0 H.O engine ? firing order is different on those (1-3-7-2-6-5-4-8)

 

Also something that you might look into is plug wires, the truck I bought recently had bad wires that were not making great connection, so sitting at idle it ran ok but when I drove around,especially turns and stops it would misfire. The way I finally figured it out was by bumping one of the wires and watching the idle change, might be worth checking especially on one you just picked up

 

I have it on the
1-5-4-2-6-3-7-8 currently I have not a clue what it was on before I changed it and then set it to that.

Sorry guys I'm new with trucks but what's a H.O engine ?

 

Yeah I've been slowly replacing things I'll have to get wires next just to be on the safe side . But that doesn't solve my issue of it not running atm

 

After dark start it and open the hood ,bad wires will light up . Bad plugs or wires will idle smooth run rough ,ck number on plugs they may be wrong .
welcome to the forum i see it,s your first post also .

 

Sounds good will do that .

Btw this is the diagram I followed earlier and then afterwards hard the backfire through the carb

 

thats a 5.0 H.O./351C/M firing order!

 

Ok well when I did that order it backfired on me. When I went to the standard 5.0 order it doesn't even seem like it's trying

 

whats the engine out of ? or, does it have a different cam in it ?

 

Does it back firing on the 5.0 HO wiring mean that's the wiring it's supposed to be set on ?

 

I was pretty sure it was just a 5.0 302ci v8 with 2bbl motorcraft carb.

& do I need to possibly reset the timing for the ignition sequence to get back in order again ?

 

if its a regular 302, firing order should be 1-5-4-2-6-3-7-8 and yes definately recheck timing, both firing orders rotate counter clockwise

 

On my cap
The 1 is just after the 12o clock mark and my clips are about 12 and 6 o clock. is that correct

 

once you get your firing order correct.. if you remove the #1 spark plug, bump the engine till you feel compression..then line up the timing mark on the harmonic balancer and timing tab.. loosen the dist. and point the rotor centered on the #1 position on the cap (i usually mark the dist body before pulling the cap).. that should be close enough to start.. after it starts slightly turn the dist. clockwise till it runs its highest rpm..then back down a few degrees that should be close enough to run till you can have the timing checked..