1978 Dodge 440: Gas has funny smell, Backfiring, etc

Maybe all of the above needs serviced. You may try some starting fluid to get it running and top off the tank with fresh gasoline and add an additive to absorb any moisture in the tank. It may also need the fuel filter to be changed.

Primary tank was full.We think it may have went bad as it sat. He says engine purrs when it is running. But, it has backfired. Maybe you are right. I will pass your suggestions to my husband. Thanks.

BelleStarr71 wrote:
Primary tank was full.We think it may have went bad as it sat. He says engine purrs when it is running. But, it has backfired. Maybe you are right. I will pass your suggestions to my husband. Thanks.

The bad smell is usually indicating old gas. If you can I'd get rid of about a half tank of the current gasoline and fill it up with new gas. Probably a good idea to change the fuel filter and put Seafoam additive in the tank when you fill it. You'll have to change the fuel filter again after a tank full has been run through.

Good luck.

BelleStarr71 wrote:
Just purchased this beast. We are brand new at this so any help is greatly appreciated. Already replaced battery, but driving it from Lancaster OH to Columbus OH it decided to not start after driving it for 3/4 of the distance. The gas smells off. Engine tries to catch, but just won't. Thinking maybe bad gas? Need plugs and wires?

Gasoline has turned; Carb is gummed up; fuel line and filter need cleaning and maybe even replacing ( Filter)

Clean everything up.....replace filters....install totally fresh gasoline and dump existing gas....try it again

Not uncommon for engines of that era to jump or break the timing chain when they're shut down. Your going to have to do a lot more inspection and testing before someone can just tell you what to do to fix this.

Backfiring is "generally" an issue with the ignition portion of the engine. Not always, but that is the first place to look.

Try getting some starting fluid and squirting it into the carb. If the engine starts even for just a second or two, then you have a fuel issue. Bad gas, clogged filter, etc.

If there is no difference after trying the starting fluid, meaning the engine refuses to run, then your problem is probably ignition.

Timing chain - Doubtful
Bad gas - maybe, but it wouldn't have run in the first place
Clogged fuel filter - Probably. If the rig has been sitting awhile, some of the gas may have gelled, broken loose and clogged the filter. (The starting fluid will confirm fuel delivery problems.)
Plugs and wires - Always a good idea to replace on an older vehicle, but to suddenly stop it from running, very doubtful.
Stuck choke - Common problem on 440's. Easy fix. Open the butterfly "flap" on the inlet of the carb if closed shut.

Another thing those late 70s Mopars were famous for was the ballast resistors going bad.. On the firewall will be a rectangular white ceramic looking thing with a plug on each end.. these acted like a fuse for the ignition system.. When they went bad it would not start.. Back then everyone carried a spare in the glovebox.. To test it unplug both ends and take a ohm meter and check the lower one from end to end and the upper one from end to end.. If either reads open then it is bad.. One side is the start circuit and the other side is the run circuit..

This is what they look like.. http://www.amazon.com/BorgWarner-RUE1-Borg-Warner-Resistor/dp/B000BZF8YM/ref=sr_1_88?s=automotive&ie=UTF8&qid=1388962442&sr=1-88&keywords=ballast+resistor

IF bad..you can jumper around the ballast resister to start it and drive it home

then replace it, the way it works is the resistor is bypassed in start mode to provide a hotter spark from the ignition
then is 'in circuit' with the engine running, so the plugs last longer

when i had my old wedge head 413, i bypassed the ballast resistor
but i had to replace the points more often because they would burn up
plugs were no problem i just when to a heavy duty plug

your 78 440 has a different distribute, mag senor no points, but the same ignition module
buy a spare ignition module and spare voltage regulator module to carry with you

IF you have that plastic body thermo quad carburetor... replace it

Born To Travel wrote:
Another thing those late 70s Mopars were famous for was the ballast resistors going bad.. On the firewall will be a rectangular white ceramic looking thing with a plug on each end.. these acted like a fuse for the ignition system.. When they went bad it would not start.. Back then everyone carried a spare in the glovebox.. To test it unplug both ends and take a ohm meter and check the lower one from end to end and the upper one from end to end.. If either reads open then it is bad.. One side is the start circuit and the other side is the run circuit..

So true. I was going to write about that, but felt I was not able to give a good description of it. Back in the day, I drove a tow truck for auto club. I always carried one. Came in handy more than once.

However, the resistor will have nothing to do with the backfiring. Just the starting.