No start on rebuilt 360LA

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jtn2655

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Recently rebuilt the motor from the junkyard. Had cylinders bored .030 over. KB107 pistons, stock crank/rods. Comp Cams XE .525/.525 cam. Rpm Performer heads, comp cams roller rockerS, RPM Air Gap intake, Holley 750 DP carb. Outside motor: MSD Magnetic pickup/mechanical advance distributor, -6AL MSD Ignition box, Holley electric fuel pump (regulated to 7psi) battery (relocated to trunk via summit racing kit) summit ignition switch panel.

Turns over smooth, getting fuel, all tolerances/torques checked. Timed +- 10 degrees. We are getting backfires but no start.
 
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Backfire through the carb means your timing is retarded! Poor some timing to that beast and let her eat! I'd recommend 12-16 deg. BTDC. 65'
 
Should not need the MSD 6A, disconnect that, and just connect your three wires to the distributor, 12v, coil negative, and ground. Make sure you are getting 12v to the distributor while cranking as well as key on.
 
Should not need the MSD 6A, disconnect that, and just connect your three wires to the distributor, 12v, coil negative, and ground. Make sure you are getting 12v to the distributor while cranking as well as key on.
And make sure you have bypassed/eliminated the ballast resistor- ready to runs need a solid 12v at all times; in crank, and run, as said by royslead.
 
Same happened to mine and I was 180 off. Its easy to do! I did it TWICE! Lol
 
THERE IS NO REASON to argue with timing on startup. LEARN to set it up and get it close and it will start and run........just like it had been run and parked the night before.

Check for compression stroke no1 ready to fire. There are two ways to do so

If the valve covers are off rotate the engine so the timing marks are at TDC and check both no1 and no6 valves. One pair will be closed and that pair is ready to fire

Otherwise remove no1 plug, stick your finger in, and bump the engine and feel for compression. As soon as you feel it, watch "for the marks" and bring the mark up NOT to TDC but "where you want the initial timing." Wiith a big cam at least 15 BTDC. Set the dist. in. If the intermediate shaft is 'wrong' the dist will not end up with no1 wire in the "factory proper" hole. THIS IS NOT A BIG DEAL

You can either "walk" the gear up and change it's position, or leave it and simply put no 1 in a different hole, that is, "wherever the rotor is pointing"

Now rotate the dist "retard" and slowly bring it back advanced until the points open or the trigger device (pickup / hall effect) is aligned

YOU CAN ALSO quickly check the timing with a light "on the starter."

Now make sure it has fuel, make sure the valves are properly adjusted and START IT UP
 
THERE IS NO REASON to argue with timing on startup. LEARN to set it up and get it close and it will start and run........just like it had been run and parked the night before.

Check for compression stroke no1 ready to fire. There are two ways to do so

If the valve covers are off rotate the engine so the timing marks are at TDC and check both no1 and no6 valves. One pair will be closed and that pair is ready to fire

Otherwise remove no1 plug, stick your finger in, and bump the engine and feel for compression. As soon as you feel it, watch "for the marks" and bring the mark up NOT to TDC but "where you want the initial timing." Wiith a big cam at least 15 BTDC. Set the dist. in. If the intermediate shaft is 'wrong' the dist will not end up with no1 wire in the "factory proper" hole. THIS IS NOT A BIG DEAL

You can either "walk" the gear up and change it's position, or leave it and simply put no 1 in a different hole, that is, "wherever the rotor is pointing"

Now rotate the dist "retard" and slowly bring it back advanced until the points open or the trigger device (pickup / hall effect) is aligned

YOU CAN ALSO quickly check the timing with a light "on the starter."

Now make sure it has fuel, make sure the valves are properly adjusted and START IT UP
This is dead on listen to this guy he knows what he is talking about! He walked me thru my electrical issues on my dart over the phone late one night and I did the break in the next morning! DEL knows his stuff and is the one guy here that is right 100 percent of the time! Well 99 percent lol :lol::poke:
 
This is dead on listen to this guy he knows what he is talking about! He walked me thru my electrical issues on my dart over the phone late one night and I did the break in the next morning! DEL knows his stuff and is the one guy here that is right 100 percent of the time! Well 99 percent lol :lol::poke:
Absolutely- the initial setup MUST be right to get it to fire up immediately. You don't want to be endlessly cranking on a fresh cam.
But there's multiple issues here- with a ready to run distributor AND a 6AL both on it (no idea how that would even be wired...?) you've got two different ignition control systems trying to operate: a single-fire and a multi-spark... They're most likely fighting each other. Get rid of the 6AL and just use the ready to run distributor to get it going (wired per MSD's instructions!), after making sure your initial is set correctly.
If, after setting your initial correctly; and getting a single ignition system wired in correctly, it's still not starting, you've got to question whether the cam was installed correctly- a tooth or more off will also have similar symptoms.
 
Correction to description(I showed my idiot card) it’s a MSD Magnetic Trigger, Mechanical Advance (part # MSD-85345)

**Update car is still backfiring, but after attempting these fixes, a new issue arose. When we set the timing as previously stated, we let off the ignition push button and the car kept cranking on its own. I had to pull the battery ground off to get it to stop.
 
Look at the starter relay switch and make sure the battery cable and the solenoid wires are not touching

turn the engine over by hand to TDC NO. 1 FIring....see where the rotor is pointing vs the no. 1 on the cab....simple
 
Look at the starter relay switch and make sure the battery cable and the solenoid wires are not touching

turn the engine over by hand to TDC NO. 1 FIring....see where the rotor is pointing vs the no. 1 on the cab....simple


The previous owner removed all the factory wiring, I have wires running from MSD box to switch panel,from switch panel to starter and battery and from fuel pump to switch panel. There is like 6 wires in the whole car right now.
 
some how those two wires on the starter are touching somewhere
 
Correction to description(I showed my idiot card) it’s a MSD Magnetic Trigger, Mechanical Advance (part # MSD-85345)

**Update car is still backfiring, but after attempting these fixes, a new issue arose. When we set the timing as previously stated, we let off the ignition push button and the car kept cranking on its own. I had to pull the battery ground off to get it to stop.
Do you have a spare points dizzy? Or a standard mopar ecu ? I'd hook up something as simple as possible to get the engine broke in then you can trouble shoot your msd issues! Is it backfiring through the carb while cranking?
 
Do you have a spare points dizzy? Or a standard mopar ecu ? I'd hook up something as simple as possible to get the engine broke in then you can trouble shoot your msd issues! Is it backfiring through the carb while cranking?
Nothing spare that would be easy to hook up, all the factory wires were cut and/or removed. That’s why I went the MSD route.

**Update 2**
Now getting fire through top of the carb consistently every time we attempt a start.
 
Here is some bad pictures of my wiring setup
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2D81F262-0DB5-4976-8975-2B3AFB690B9F.jpeg
D703F4FA-5534-4BAB-ABB2-52740A2DFF2A.jpeg
 
Nothing spare that would be easy to hook up, all the factory wires were cut and/or removed. That’s why I went the MSD route.

**Update 2**
Now getting fire through top of the carb consistently every time we attempt a start.

If you set the dist up like I posted earlier, you have an intake valve(s) hung open. Check valve lash. And DID YOU set the dist. up as I posted? Otherwise "timing" is a crap shoot. And double --triple check your plug wires/ firing order..........wires go clockwise around the cap on a Mopar SB. No1 is driver side front, no2 is pass side front. Check CAREFULLY you do not have 5 and 7 switched
 
If you set the dist up like I posted earlier, you have an intake valve(s) hung open. Check valve lash. And DID YOU set the dist. up as I posted? Otherwise "timing" is a crap shoot. And double --triple check your plug wires/ firing order..........wires go clockwise around the cap on a Mopar SB. No1 is driver side front, no2 is pass side front. Check CAREFULLY you do not have 5 and 7 switched

Yes both valve covers off, checked 1 and 6 both were as you said. 1 closed and 1 ready to fire. Set distributor to #1 +-0-15 that’s when we saw the fireballs. Plug wires are all good, correct firing order checked 69 times.
 
Yes both valve covers off, checked 1 and 6 both were as you said. 1 closed and 1 ready to fire. Set distributor to #1 +-0-15 that’s when we saw the fireballs. Plug wires are all good, correct firing order checked 69 times.
Now you have me stumped. I want to know whats wrong with it. Lol
 
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