Newbie here, first time owner of an older ford. I have a 75 f150 super cab with the ford 460 and edlebrock 1406. I drove the truck on its first long trip, two hours one way. Driving back today, I was 30 minutes from home and got up on the interstate when the engine presumably backfired twice and died on me. I was able to get it started again and back to a gas station, but it dies when I put in drive. If I can get it to idle in drive, it dies when I give it gas. I can hear a vacuum leak, but it's had one since I bought it. Any help will be greatly appreciated!

Update: Got the truck towed home but was able to drive it off the truck and into my driveway. It idles ok but sputters a lot more than normal.

 

Glad you at least got it home.
Kind of hard to diagnose the problem long distance. You'll need to do some troubleshooting.
First, check and make sure you have fuel at the carb. Look down the throat of the carb and work the throttle, you should see two strong jets of gas spray into the throat of the carb.
Seeing as you can get it to run, you have spark. If you have a timing light, check the timing.
I would definitely look at the vacuum leak you said that it has.
I have also seen a bad DS II ignition box act like that.

 

Thanks for the reply, mikeo. I'm going to check that at some point today, but I've been intending to rebuild the carb regardless. Now I guess I have a good reason. It did happen as soon as rain got bad so maybe it has something to do with bad wiring? The wires are all exposed and there is a lot of missing weather stripping. Everything has been working as is should save the instrument cluster. As long as there is nothing wrong with the engine internally or the transmission didn't pop on me I'm pretty confident I can fix it.

EDIT: It has given me trouble starting the entire time I've had it. hesitant to crank but drives fine. Maybe the ignition has something to do with it.

 

Welcome to the FTE.
Well at least you do know that there are wiring issues. And like Mike mentioned checking your timing. That's really kind of what I'm thinking too. If you remove the distributor cap, and rotate the crankshaft side to side a bit (less than a couple of inch's) you should see that rotor in the distributor move with it.
If it takes more than a couple of inch's to see that rotor move, that timing chain may be week/loose enough to where it jumped timing. You could also remove the fuel pump, then should be able to stick a finger in the hole and feel the timing chain. But you'll have to try to find the middle area to the chain doesn't have tension on it, if that makes any since.
Far as hearing a vacuum noise, does the carb have an air filter on it? If not, then your just hearing the carb.
Unk Bob

 

So I cranked it this morning to move off the grass so I could cut the lawn. Had it sitting all day and just cranked it up. Everything seems to be fine. I'm thinking it has something to do with wiring since it happened during a heavy rainfall. Is there any way to diagnose this? I'm going to replace the plugs and plug wires as well as rebuild the carb. How difficult is it to rewire these things? Should I get a professional to do it?

 

I had the same thing with my buddies bronco... After looking and fixing there are a TON of things that can aparently cause this issue. One of them had to do with a locked up torque converter, vaccume leaks, cab seals, and timing. Luckily for me the timing got a bit goofed up from the previous owner that rebuilt it. Same troubles as you, idled perfectly fine, shifter perfect. But the instant that the gas was hit it would cut out and die. I'd start with the timing like mentioned above, then the vaccume leak issue as it may make it easier to diagnose the other problems. Then get a new base gasket for the carb to the 460 also while you rebuild. A lot of people I know try to reuse them. As for the rewiring, these trucks are extremely easy!! A bit of reading and research and shouldn't be a hassle. Any other questions about my specific situation on the bronco just PM me! I can help walk ya through some of the suff I did.

 

But the OP has a 1975, so it may not have DuraSpark because not all vehicles came with it until 1976.

The DuraSpark module used in 1974 is 1974 only. The DuraSpark module used in 1975 is 1975 only.

Both of these modules were turds, Ford techs referred to them as NeverSpark!

DuraSpark II module introduced in 1976.

 

Thanks for the info. I'm thinking it may be timing...since I've had it, it has idled a little rough and seems to sputter/pop every 6th or 8th firing. Here are my priorities.

1. Rebuild carb (and replace accel pump if needed)
2. Replace plugs
3. Replace plug wires
4. Wrap exposed wiring in elec tape
5. Check timing
6. Replace ignition module


Wish me luck...!

 

Update for everyone!

I did all the above and she's running beautifully. The carb was disgusting and I tightened up some vacuum lines so she's purring now. All that's left is to fix the exhaust.

NOTE: i did find some oil on the plugs for 3 and 4. Gonna have to remove the gasket cover and see if I can spot the issue.