ToddMcF2002
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MSD Dead - Help with direction please
- Thread starter ToddMcF2002
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There is ABSOLUTELY NOTHING that this guy has to say, is relevant to this subject, or in fact just about any subject. Im not asking for his comment or opinion....period.
BOB RENTON
I doubt they would tell anyone how their product works. Why would they give away any trade secrets? It would be like asking KFC how they make their chicken so tasty.
On the Pertronix III, if you use an inductive timing light, it will not be accurate and flutter around. If you use an electronic light meant for multi spark, it will show steady and clear. I've tried them both on my car. My old Sears light just won't work on it.
ToddMcF2002
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I'm a bit confused by this video:
The guy is installing his distributor intermediate shaft perpendicular to the crank instead of parallel but his rotor looks like its pointing to #1 in the right place? I thought you wanted the slot parallel to the crank like this?
The guy is installing his distributor intermediate shaft perpendicular to the crank instead of parallel but his rotor looks like its pointing to #1 in the right place? I thought you wanted the slot parallel to the crank like this?
MSD loves voltage. The resistor should have been removed or bypassed.
ToddMcF2002
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Any thoughts on the post above regarding the distributor intermediate shaft alignment?
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Clearly the aftermarket distributor pictured is clocked differently than an OE distributor.
ToddMcF2002
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Still sort of new to Mopar so I need to check / confirm these things so I don't destroy my RB. Thanks.
Distributor body needs to be oriented with the vacuum advance pointing to driver side, for clearance issues. TDC on motor, rotor needs to point to #1. Orientation of wires can be altered clockwise or counterclockwise so rotor points to #1. It is a deviation from norm but I have seen it done and it will work that way.
Jeremiah
Well-Known Member
Wow...a LOT of speculation going on in this thread.
All you need is a Pertronix ignitor 1 and swap in a 3 ohm coil if you want to bypass the ballast. If the trusty old flame thrower can light off a 175 shot of nitrous and fire off my 451 with the comp xe294h on the first crank it will be more than adequete for 99.5% of the cars on this forum.
All you need is a Pertronix ignitor 1 and swap in a 3 ohm coil if you want to bypass the ballast. If the trusty old flame thrower can light off a 175 shot of nitrous and fire off my 451 with the comp xe294h on the first crank it will be more than adequete for 99.5% of the cars on this forum.
ToddMcF2002
Well-Known Member
I think I have a bad ballast resistor. Its measuring 12V in and 3.52V out to the coil which I thought was supposed to be around 7V? Also when I crank the starter voltage is constant at ~3.5V - which I thought during cranking would jump to around 12V (IGN2) and stay at ~7V during run (IGN1)? Sound like a dead ballast? Its also hot to the touch but I'm not sure if that is expected on a double ballast...
If the ballast is hot it's likely still working as they fail open circuit. But yes your readings appear to be low
So what distributor do you have in there?
The pickup polarity may be swapped.
Two pretty simple tests.
Pull the distributor out set the coil wire about 1/4" from a good ground test for spark by twisting it with the key in start and run position. Spark should be blu/white and crisp.
If so (spark looks good) double check timing on compression stroke and firing order.
The ballast will get hot if you have the key on for a while without the engine running. ( Try not to do that)
So what distributor do you have in there?
The pickup polarity may be swapped.
Two pretty simple tests.
Pull the distributor out set the coil wire about 1/4" from a good ground test for spark by twisting it with the key in start and run position. Spark should be blu/white and crisp.
If so (spark looks good) double check timing on compression stroke and firing order.
The ballast will get hot if you have the key on for a while without the engine running. ( Try not to do that)
ToddMcF2002
Well-Known Member
Thanks Don. I did a little more diagnosis and I don't think its the ballast resistor. The Chrysler ECU plugged in drops the voltage to the coil. If I unplug it the voltage jumps to 12V. Its putting .5V on the magnetic pickup (grey wire, ECU side of the harness). I tried a variant of what you said because I have one of those bolt type spark testers. I haven't tried the "pull the distributor and spin it test" but I did try grounding the grey wire (ECU side) with a test light which should mimic the distributor spin. Didn't work so I'll pull the distributor tomorrow and try it the way you suggested. I talked to MSD and the orange wire is positive on the magnetic pickup so I don't think its wired backwards but I'll check that tomorrow too. If I was a betting man at this point I'd say bum coil - should be able to confirm that tomorrow.
Well if the coil turns out to be bad then the MSD is likely to be good.
I'm not familiar with the grounding of a wire to trigger the ECU but it seems incorrect to me
I'm not familiar with the grounding of a wire to trigger the ECU but it seems incorrect to me
ToddMcF2002
Well-Known Member
Yup the MSD would be good in that event. But I'm still going to pull it in favor of the Chrysler stuff. For $20 I'll keep a spare ECU in the trunk. Fast forward this video to the 12:20 mark you can see how this guy simulates the pickup its pretty neat.
ToddMcF2002
Well-Known Member
I’m getting my butt kicked by this ignition. I bought an OEM type coil and I’m finally seeing some intermittent spark on the testor. I tried the magnet pickup both directions and it’s intermittent. She won’t start. Voltage on the coil is still 3.52V which seems real low. I’m starting to wonder if I should try bypassing the resistor with the Pertronix coil and try 12V? I did a resistance test on the Pertronix coil and I don’t see anything wrong with it. I’m stuck.
Yes that voltage is low.
Do you maybe have the start wire from the ignition is on the 5 ohm side?
The pugs are keyed but maybe the wire is spliced on the wrong side.
Do you maybe have the start wire from the ignition is on the 5 ohm side?
The pugs are keyed but maybe the wire is spliced on the wrong side.
ToddMcF2002
Well-Known Member
I have it wired like this - 70 diagram. Blue wire to coil. Brown wire is IGN2. The voltage drop is coming from the ECU. As soon as I plug it in the voltage drops with the key in RUN on the resisted side of the resistor (left side). When I crank it I thought that the brown wire (IGN2) would override the voltage on the resistor for 12V during cranking (IGN2) and drop back down once the key was back to RUN. I'm not noticing any jump in voltage during cranking. That's why I'm considering bypassing the resistor and using an internally resisted coil (Pertronix). At this point though I'll try anything!
Check your bulkhead connector you should have battery voltage at the coil during start.
Test for spark in start and run like I described.
I don't like doing it but try a jumper wire to the coil just as a test
Test for spark in start and run like I described.
I don't like doing it but try a jumper wire to the coil just as a test
ToddMcF2002
Well-Known Member
I have nothing left to try but pulling the distributor. I tried jumping the coil direct to battery. Coil sparked once and then I got smoke on the jumper wire at the battery positive terminal. I thought that’s how people stole these cars in the 70’s??? I have to admit it I’m nearing defeat here.
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