Hi all,
Thanks for the advice so far. Unfortunately, it seems I still have a problem. I did try reversing the polarity of the wires. I do not get even a pop then, so that unfortunately did not fix it. I went ahead and ordered a new pickup, got the "better" quality Standard one. Still made in China but put it in. The air gap was a little finicky but finally got it sorted. Put it in. No fire. Decide that even though there is 5000 feet of water just off the North shore I would probably regret towing it down and pushing it into the Caribbean. So, to eliminate things, I go back and test the system. First, I pull the coil wire and jump the ends. Still good spark. Try rotating the distributor, nothing. It seems that the distributor pickup works better spinning. Somewhere in here I break one of the wires from the pickup so have to fix that. I then pull the distributor and stick a big screwdriver into the coil wire end. Spin the distributor. Great spark. Grab the screwdriver too close to the shaft. Discover there is definitely an excellent powerful spark. Put vocabulary from a lifetime of sailing to good use. Next, pull a plug, decide to start with # 1 cylinder. Plug is black wet and dripping petrol (at $4.00 a gallon here). Hook plug up to coil wire, rest plug on bare bit of engine. Spin distributor. Get noisy spark and puffs of smoke but not across gap. Most of the sparks are way up inside the plug and sort of bouncing around the center insulator and the body of the plug. I go ahead and clean the center electrode and the ground strap and spray it all down with brake cleaner. Put it back on engine and spin distributor. Eventually get good spark across electrode. Proceed to do the same process to all 8 plugs. Discover that # 5 has a cracked insulator so will have to deal with that. Still, the other 7 should have fired so that is not the big problem. After ensure that all the plugs are clean and pass the spark test on the coil wire, I hook everything up and try starting up car. Fires right up, then gets progressively worse and eventually dies. Try to start again, nothing. Take out # 1 plug. Soaked again. Hook up to coil wire and do the spin distributor test. Eventually cleans up and sparks properly. However, engine does not.

MSD seems to be working fine. Pickup is functioning, at least when doing the manual spin test. The MSD unit itself is hard wired directly to the battery with # 12-2 marine wire(essentially a wire with 2 conductors) so I think the ground issue as far as the MSD is concerned is good. I have done nothing to the carbs. Turned on the fuel pump, removed the air cleaner on the forward carb and looked down it while the engine was off. Nothing leaking, so I do not think the pump is over pressurizing. Still, the plugs were soaked almost immediately.

I am starting to think multiple problems. The spark side seems good. However, the plugs looked a bit worn, and Dan had a fair amount of dyno time on it dialing in the carbs. I am thinking replace all the plugs to be certain. They are NGK, have to double check the part number.

I have added an additional ground from the engine block directly to the battery. No change on the ignition front unfortunately, as I am a believer in the ground everything school of thought. The starter loves it.

Anyway, help before it becomes a mooring.

Tomorrow going sailing with Michelle on a friend's trimaran to practice for the BVI Spring Regatta. All wind powered, no spark plugs, no carburetors, very refreshing.......

Like you said... replace the plugs... crank it over
with all the plugs out to make sure the engine doesnt
have a pile of fuel in it

Did u try a new cap & rotor?

It could be the coil.
I want to say it's in the carb. It sounds like it's flooding and getting the plugs to wet to fire. Or the coil is going away as it warms up.

I'm gonna risk embarrassing myself again by opening my mouth once more...

Have you checked the battery on this thing? And the alternator? Could it be a weak battery?

You said at one point after you cleaned the plugs it fired and ran briefly then died. If the alternator was not charging the battery, that could happen, especially with an electric fuel pump that requires a lot of continuous voltage. The MSD likes full voltage for sure. Maybe put a charger on the battery and try to start it or at least check the battery voltage to see if it's good.

Does it crank over fast and not fire or does it sputter and not start? If you keep trying to start it without firing obviously the plugs are gonna get wet and the battery will lose voltage. Then you're fighting wet plugs and less than optimal spark energy.

When I went through an MSD problem last year I almost always needed the charger on with the crank assist to get the motor to spin over fast enough.

Regardless of the problem, sounds pretty annoying.

As already suggested, check the floats and needles and seats in the carb. for the fuel problem. Most of the local pump gas fuel here in the states goes really bad in less then 45 days in mild temps. faster and quicker in the summer It loses it octane and gets really hard to start Race gas can be worst if it sits where it is hot or the lid is open a little bit It ran good before, it doesn't run good now, it has sat for awhile Let us know the final fix is

Hi all,

Thanks again for the input. I appreciate it all, the only other 70 B body down here has the roof sitting on the floor pan underneath a tree, so definitely an orphan. I appreciate all of the input and suggestions as I have no Mopar specific people down here to bounce ideas off of.

So, I have 8 new plugs coming down from Rock Auto. Gotta love them, as soon as I put in my zip code it switches to USPS Priority mail. I have to plead with most people to get them to use USPS to here.

So, blew like stink here over the weekend, friend cancelled on sailing. Caught up on work, then worked on car a bit more. Decided to check the basics. Cleaned the plugs again, double checked the plug gaps, realized they were on the high side, set them to .032. Left the plugs out for the day to let the cylinders air out. Turned the engine over a few times with a breaker bar and socket. Then, decided to look at the distributor again. The instructions with the new pickup had a comment about making sure the reductor was in the correct spot. The reductor was in the wrong spot which could have explained some of the tuning issues on the dyno but to be fair I had taken it off but paid attention to it so I believe it was back in the same spot as before. Next, I rotated the engine until the harmonic damper points to 15 degrees before TDC. Set the distributor so that the point on the reductor was in line with the pickup. Rotor definitely pointing to the wrong location. Pulled distributor, yanked off reductor, pulled it in other location. Now rotor lines up with terminal. However, noticed there are chunks missing from reductor but should be enough to get a signal. Somewhere in here I show Michelle how if I spin the distributor we get a good spark across all plugs. She thinks it is cool and wonders how to incorporate it into one of her classes. At that point we head over to a friend's house for a Superbowl party. As she is from Jamaica and most of the other people are from the Caribbean not sure how much we will be paying attention to the game but the fresh caught conch was good along with the homemade rum punch (tamarind with some ginger and lemon and of course decent amounts of Cruzan). Left at half time, I think it was tied but had high hopes that the Windies would pull it out. Wait, that is cricket.

Anyway, today put the plugs in and hooked up the wires. Cranked it over and actually fired up. Ran for a bit with a fair amount of throttle work. Tried to keep it running long enough to attempt to mess with the timing to at least get her to run at idle. Almost succeeded. Was able to leave driver's seat and head to front of engine and wind in a bit of advance. Idle improved and then kawoomp, backfired and died. Got it fired a little bit a couple of times but never as good as before. Then, it got worse. Tried switching the fuel pump off to see if the pressure was too high and flooding it out. This seemed to improve it but somewhat tenuous. Getting a lot of backfire issues into the intake, not sure if that is timing or lean. Have a hard time believing it is lean. Backfiring in the intake manifold is a theme right now. Intake is a Weiand tunnel ram with 2 x Holley Ultra HP 600's

Carbs are new, but not sure what has been done to them. Did not have it running long enough this last time to put a timing light on it.
Battery is an Odyssey Group 65, brand new. Starter is a Robbmc starter, cranking is good. I am pretty sure the MSD is getting
power as I know they are sensitive to that. Have been putting it on a charger to ensure that.

Here is a youtube video of the one time it ran any distance. I shut it off but she did not know that.
https://www.youtube.com/watch?v=1mEnweacxIE

Thoughts on timing in terms of backfiring into the intake? Probably time to check the carbs again but again this engine ran on the dyno so reluctant to change too many things.

Best, Dave

Verify the spark plug wires, make sure there not switch between the easy ones like #5 and 7 and #4 and 6 Back firing now sounds like either a spark plug wire or distributor cap issue

Sounds like the plugs are junk to be honest. Champions are the most noted for it, but most standard style copper plugs seem to die once they're flooded once.

So it fires and runs with a lot of throttle input. Maybe re-set the idle mixture screws on the carbs to a baseline and start from there. Have you verified the transfer slots? Have you checked for any vacuum leaks?

Or maybe start taking big swings at it, like advancing or retarding the ignition timing a bunch just to see what happens. Advancing it might help to keep it running then you can back it off while you try to dial in the idle.

In stock ignition system cars, I would swap the coil, then if no improvement, remove the idle screws on the carb and blow compressed air into the holes to hopefully dislodge any dirt in the idle circuit.

Thanks again for all the help. I worked on it a bit more last night and have found a few things. I verified the timing, set it statically to about 18 BTDC, by the process of lining up the reductor with the pickup (I believe that should work close enough). I pulled the #1 plug and checked the spark using the jumper wire trick and the plug attached to the coil wire. Initially the spark was not jumping to the ground strap but rather sort of scattering around the center insulator. Finally it did spark across the gap. As suggested by a couple of people, I tried swapping coils. I took the Lucas Sport coil out of Michelle's Land Rover as I knew it was good and it puts out a pretty good spark. Basically about the same as the yellow Accel coil in the car. Put the plug back in, tried starting it. A couple of pops but that was it. Noticed that only the #1 header tube had any warmth. Next, tried a different plug using the jumper wire and coil wire test. It never really sparked at all. Then, I remembered I have a spare set of brand new plugs for Michelle's Landy. They will not fit the RR but will work fine for testing on the coil wire. Hooked up one of the new plugs. Nice solid spark across the gap. Either coil produced the same result.

I also took Rmchrgr's advice and made up a better set of jumper wires to test the polarity without having to cut wires. Seemed to spark the same when doing the spin the distributor while out of the engine with plug attached to coil wire test. Not sure if in that situation the polarity difference would even show up but tried it both ways. I did try starting it with either polarity set up and neither worked. When I do get it running I will confirm as suggested.

To clarify my earlier post, it really only ran that one time after I had cleaned the plugs. It got worse and worse then backfired and died.

Carburetor settings: idle screws are about 1-1/4 turns out, unchanged from how the engine arrived. Carbs are brand new, just dyno time. idle jets are 32 and the idle air correctors are 73. I think it would have done better and at least sort of ran on the squirters better than it does.

Good question on the transfer slots. They are not exposed at all. It seems that Dan set it up to run on the idle air bypass. However, when it did run that one time up and down the hill that is how it was set up, idled around 1000 RPM. Any thoughts there on that set up? I have not changed anything on the carbs from how they arrived, in terms of idle speed screws and idle mixtures. I did disassemble them to verify what jets and air correctors are installed but did not change any.

Fuel is pretty new.

I am really coming around to the plugs being bad, as also suggested. This is based upon how well the test plug worked, and also that the #1 plug seemed to behave better. At some point last night I remembered that this past summer I bought 1 new plug as when the engine arrived here there were only 7 plugs in the box of miscellaneous parts. I am pretty sure I put that new plug in # 1 as I put the rest in before we went up to the states and left 1 as it is the easiest to reach. At this point until the new plugs show up I think trying anything else is just going to wash more gas through the engine which can not be good. The plugs are NGK R5671A-7. Engine is 452, around 10:1 compression, Edelbrock Performer RPM heads, cam is 257/267, .6 lift, Weiand tunnel ram and 2 x Holley Ultra HP 600 carbs if anyone has thoughts on that plug selection. Those are what came with the engine.

As frustrating as it is, last night I was working outside in a t-shirt, at our little house about 800 feet up a hillside on an island in the Caribbean, watching the full moon come up over Buck Island and the water. Things could be a hell of a lot worse.

Best, Dave

Well, it runs.

Thank you to all that contributed. Last night I took the plugs out and used the propane torch trick suggested. I checked each plug for spark off the coil wire, triggering it with a jumper wire. I then checked and rechecked the static timing, along with the reluctor air gap. The pickup coil was not quite parallel to the teeth on the reluctor so futzed with it until it was better. After static timing, I fine tuned the air gap until it sparked each time I moved the rotor back and forth. Hooked up the wires and it fired right up. Kept it running, it died once as it was still cold. Michelle helped me keep it running and I hooked up a timing light to it. Full advance is around 34-36 degrees or so, initial is around 20. Will have to clean up the marks a little bit but it is very close. To test it again I just fired it up this afternoon. It ran fine until the coil wire fell off the coil. I have the coil mounted horizontally on the top of the inner fender so I think I will relocate it to the side of the inner fender and mount it vertically. That way gravity is working for me. It was hooked up when this problem started.

I think it was a one problem leads to another situation. The pickup was dying or air gap was off, which led to poor running, which led to fouled plugs. I also believe the reluctor was in the wrong position so I am surprised it ran as well as it did the one time I drove it up and down our road. Once the plugs were fouled they would not work well enough to keep running. I might have not have had the new coil pickup perfect either but I certainly spent a good chunk of time on the clearance initially but I think the final check with the twist the rotor test is a good one.

Once the new plugs arrive I will go ahead and put them in as one has a cracked insulator.

That number of NGK plug is the hottest they make in that model. It is described as a good street/strip plug. Open to suggestions for sure.

I will say it sounded as if it had a much cleaner idle last night.

I will start a new thread on the transition slot not showing at all when I had the carbs off.

Thank you again to all.

Best, Dave