Good Morning,

I have a 1978 440 out of a motorhome that I put in my Challenger. It will not start, just backfires once in a while
up through the carb. Engine did sit in a garage for a few years before I installed it. Ran the oil pump for about
15 minutes with a drill, seemed to have good oil pressure. Has what appears to be maybe a weak spark (put one
of those cheap inline test lights with the #1 plug).

Here are some things I have done:

Replaced the ECU, twice. Verified it is grounded. I am using an original NOS unit for a 73 Mopar.
Replaced the Dual Ballast Resistor, twice
Upgraded the coil to an Accel, then MSD Blaster
Replaced the Distributor
Verified all wiring.
Set timing to 10 BTDC without vacuum advance

At this point I am stumped.

Any help would be greatly appreciated

Thanks,
Jim

Ii either has good spark or it dose not. Should have a nice blue arc out of a plug wire 3/8 of an inch. If so verify compression, verify the distributor is at TDC compression stroke.

You know the drill, compression, fuel, spark, timing, valves that aren't stuck, pushrods in place and not bent... I'd would probably run a hot wire from the battery to pos coil to see if the spark improves. You seem to have covered everything else sparkwise.

Might have jumped a tooth on the timing chain? Nylon tipped gear.

Dist. 180 out?

Joe

This

Knowing I’d tdc is really tdc would be good. Worth a check.

Easy thing at this point would be to bar it over to tdc indicated, then pull distributor. Look at drove slot in the gear. Should be parallel to the crank, or in other words straight across. If it’s close but slightly off, by not much with the timing mark right on tdc, you are 180 out. Roll engine over again to the tdc mark and it should be straight across now. Then reinstall distributor and make sure your rotor is close to number 1, also great time to check firing order.

If you put can’t picture how the gear will look, this will make more sense once you see it both ways, tdc and 180 out.

jlatessa called it, distributor 180 out, ugghhhh. I checked it like 3 times, never fails.

Runs smooth as hell now.

Thanks Everyone!!

jim

Just heads up. when you line the dots up on the timing markers, its on the exhaust tdc. So if we bring the dots together, piston at tdc. and put the dist. in, its 180 out.

Yep & Yep.......OR the ever popular......firing order of plug wires are correct on the cap....but not COUNTER-clockwise like a big block. Ask me how I know this stuff? It's because I make a lot of mistakes and remember stuff One more tip...IF you are indeed "180 out" and you have at least a little slack on all your plug wires, then the easiest way is to move the #1 wire at the cap straight across to the other side of the cap & then move all the other wires appropriately, following the fire order, counter-clockwise. On the other hand, if you don't have any slack, you can also remove the distributor hold down, move cap/wires out of the way, lift up distributor 1", turn rotor 180-degrees, drop distributor back straight down....etc.

I have a 78 440 out of a motor home in my pickup. I had the same problem. There are 3 grooves in my harmonic balancer, thought I marked the right one. Couldn't get the damn thing to run. Finally pulled number one spark plug, brought it up on compression stroke and low and behold, I marked the wrong groove. Checked the distributor and it was way off. Set the distributor so the rotor was pointing at number one and it fired right off. It's the simple things that screw most of us up.

I thought Chrysler small blocks would run 180 out, not great, but would run. True or not?

Nope, BTDT, not true. Well, unless you're a complete screwup and install the cam 180 degrees out, DAMHIK about that..