70 up charging system upgrade question

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Removed 16 Ga fusible link from starter relay stud, and measured resistance from there to the red "batt" wire at terminal end 0.1 ohms resistance ....minor?(Remember Mad bypass)
I thought "IF" there is a 2 v drop at ign1, this would be where it is? 0 resistance tells me it's good?

20181007_131445.jpg
 
Checked for resistance continuity at connections I had done. All seem good.
Batt -ve was unhooked while doing these tests.
1.Zero ohms from red batt at ign switch and the red and black leads from ampmeter(now connected together Mad bypass)
2. Zero ohms 16ga fusible link at starter relay and again to red black ampmeter bypass connections.
Thanks all.
 
Steve you cannot (usually) find this with resistance checks. This is because things like connector terminals and switch contacts, or sometimes splices or wire crimps, are usually the cause, and the heat up and change under load. Also "the wiggle test" sometimes.

A good example is the ignition switch, think what you have

You have the power in CRIMP to the connector TERMINAL, the CONNECTION between the connector terminal and the switch terminal itself, then through the switch CONTACTS and out on the run terminal, and again the CONNECTION between the switch terminal and the connector terminal, and once again the wire CRIMP at the blue wire.................then the blue wire goes out through the bulkhead and once again you have CRIMP, the CONNECTION between the two bulkhead terminals.........and the CRIMP at the enging bay end on the blue

Follow this like a road map. As the wire progresses through each crimp, terminal conneciton, switch contact, etc, there is/ might be "a little or a lot" of voltage drop.

If you measure say, 12V backprobing the power into the ignition switch, and the blue coming out shows say, 11.8, then you know right there in your hand is a .4V drop. It is right there in those 2 wire ends, the crimps, the connections and or the switch.

One way to check the switch is to get some good quality individual "push on" flag/ blade terminals that fit the switch TIGHT and crimp / solder them to some scrap no 14 wire. Clean the switch terminals really good, nice and bright. "Rig" this up with a load, to a battery in fact you can clip lead it right into the car where it came from, and then clip your meter across the power in and the blue. Now you have pretty tight connections at the switch. If you measure any drop across the switch........and wiggle the key........see if it changes, now you know it is right in that switch itself.
 
I agree with all the connections/crimps with voltage drops. I thought they may/would show up in resistance tests, and I understand the temp/load could also cause an increase in resistance.
Ok I did this test before reading your last response. I'll read your reply and try to saturate. Heres results from last test.
Ecu and ballast unhooked, everything else connected.
Volt measured at ign2 ballast terminals and direct to batt -ve.
Key on 0 volts
Key off 0 volts.
Key start 10.16 V.
I'll read you last reply.
67Dart273 said:
Steve you cannot (usually) find this with resistance checks. This is because things like connector terminals and switch contacts, or sometimes splices or wire crimps, are usually the cause, and the heat up and change under load. Also "the wiggle test" sometimes.

A good example is the ignition switch, think what you have

You have the power in CRIMP to the connector TERMINAL, the CONNECTION between the connector terminal and the switch terminal itself, then through the switch CONTACTS and out on the run terminal, and again the CONNECTION between the switch terminal and the connector terminal, and once again the wire CRIMP at the blue wire.................then the blue wire goes out through the bulkhead and once again you have CRIMP, the CONNECTION between the two bulkhead terminals.........and the CRIMP at the enging bay end on the blue

Follow this like a road map. As the wire progresses through each crimp, terminal conneciton, switch contact, etc, there is/ might be "a little or a lot" of voltage drop.

If you measure say, 12V backprobing the power into the ignition switch, and the blue coming out shows say, 11.8, then you know right there in your hand is a .4V drop. It is right there in those 2 wire ends, the crimps, the connections and or the switch.

One way to check the switch is to get some good quality individual "push on" flag/ blade terminals that fit the switch TIGHT and crimp / solder them to some scrap no 14 wire. Clean the switch terminals really good, nice and bright. "Rig" this up with a load, to a battery in fact you can clip lead it right into the car where it came from, and then clip your meter across the power in and the blue. Now you have pretty tight connections at the switch. If you measure any drop across the switch........and wiggle the key........see if it changes, now you know it is right in that switch itself.
Click to expand...
 
Cleaned up switch connections nice n shiny.
Measured volts, with everything hooked up and meter leads weaselled into the back.
Key on, getting 300 mV?? Meter jumps around a bit too.
Remove switch and measured at same 2 plug connections and get 11.13V. Static V is 12.20V.
This would indicate a 1 volt drop?
Thanks all.
67Dart273 said:
Steve you cannot (usually) find this with resistance checks. This is because things like connector terminals and switch contacts, or sometimes splices or wire crimps, are usually the cause, and the heat up and change under load. Also "the wiggle test" sometimes.

A good example is the ignition switch, think what you have

You have the power in CRIMP to the connector TERMINAL, the CONNECTION between the connector terminal and the switch terminal itself, then through the switch CONTACTS and out on the run terminal, and again the CONNECTION between the switch terminal and the connector terminal, and once again the wire CRIMP at the blue wire.................then the blue wire goes out through the bulkhead and once again you have CRIMP, the CONNECTION between the two bulkhead terminals.........and the CRIMP at the enging bay end on the blue

Follow this like a road map. As the wire progresses through each crimp, terminal conneciton, switch contact, etc, there is/ might be "a little or a lot" of voltage drop.

If you measure say, 12V backprobing the power into the ignition switch, and the blue coming out shows say, 11.8, then you know right there in your hand is a .4V drop. It is right there in those 2 wire ends, the crimps, the connections and or the switch.

One way to check the switch is to get some good quality individual "push on" flag/ blade terminals that fit the switch TIGHT and crimp / solder them to some scrap no 14 wire. Clean the switch terminals really good, nice and bright. "Rig" this up with a load, to a battery in fact you can clip lead it right into the car where it came from, and then clip your meter across the power in and the blue. Now you have pretty tight connections at the switch. If you measure any drop across the switch........and wiggle the key........see if it changes, now you know it is right in that switch itself.
Click to expand...
 
67Dart273 said:
How does the "big red" (battery feed) get through the bulkhead? Is it still "the connector" or drilled through and wire straight through?
Click to expand...

Sorry Del, I missed this question. Red wire is solid thru bulkhead, I drilled bulkhead out and ran a length.
 
67Dart273 said:
If you measure say, 12V backprobing the power into the ignition switch, and the blue coming out shows say, 11.8, then you know right there in your hand is a .4V drop. It is right there in those 2 wire ends, the crimps, the connections and or the switch.

One way to check the switch is to get some good quality individual "push on" flag/ blade terminals that fit the switch TIGHT and crimp / solder them to some scrap no 14 wire. Clean the switch terminals really good, nice and bright. "Rig" this up with a load, to a battery in fact you can clip lead it right into the car where it came from, and then clip your meter across the power in and the blue. Now you have pretty tight connections at the switch. If you measure any drop across the switch........and wiggle the key........see if it changes, now you know it is right in that switch itself.
Click to expand...
Del, I'm following you here, now when i make the jumper wires from ign switch to ign switch connector, do I make jumpers for ALL 5 of the connections?
It's easier to get meter leads connected safely then?
Thanks
 
No just the immediate path. Dont worry for now about start, accessory, etc, you are "going down one road" at a time. Power through the switch to ignition.....just two wires. What you are trying to determine, is "the drop" inside the switch, or right at the terminals of the switch/ connector? I have found at least two, over the years, where the CRIMP itself at the terminal was the problem. This is difficult to get to but THINK of them as each a separate part

This may be a poor example. What I'm trying to get at is wherever the drop changes "a lot" is right where the problem is. As you move one way or the other with your probe along that path, wherever the drop "is" will change the reading
 
Ok, I wasnt sure if just having 2 wires jumped would give "proper" test results. I'll make a couple jumpers at work. Back in for 4 days in a row, so limited time again.
Thanks for chiming in Del.
The test results I posted above in reply 55, does that look like a 1v drop in wiring itself? Key switch was removed for test.
Thanks again.
67Dart273 said:
No just the immediate path. Dont worry for now about start, accessory, etc, you are "going down one road" at a time. Power through the switch to ignition.....just two wires. What you are trying to determine, is "the drop" inside the switch, or right at the terminals of the switch/ connector? I have found at least two, over the years, where the CRIMP itself at the terminal was the problem. This is difficult to get to but THINK of them as each a separate part

This may be a poor example. What I'm trying to get at is wherever the drop changes "a lot" is right where the problem is. As you move one way or the other with your probe along that path, wherever the drop "is" will change the reading
Click to expand...
 
Last edited:
So had a few minutes tonight after work.
I rigged my negative lead on meter direct to battery -ve.
I made 2 jumpers, 1 from batt(red) and 1 from ign1(2 blues)
I also have 2 switches.
Battery static 12.32 V
Results
Original switch
Key off 12.10 V at red battery
Key on 11.34 V at red battery
Key on 11.18 V at Blue ign.
0.20-0.16V drop. Looks minor to me thru switch, but red wire has 0.76 V drop?
Spare switch
Key off 12.02 V at red battery
Key on 11.30 V at red battery
Key on 11.12 V at Blue ign.
Similar results as original switch? Drop in red wire of 0.72 V.
I'm thinking the problem lies in the circuit I've taken a pic of.
Also posted pic of ign switch with jumpers.
Thanks all.
67Dart273 said:
No just the immediate path. Dont worry for now about start, accessory, etc, you are "going down one road" at a time. Power through the switch to ignition.....just two wires. What you are trying to determine, is "the drop" inside the switch, or right at the terminals of the switch/ connector? I have found at least two, over the years, where the CRIMP itself at the terminal was the problem. This is difficult to get to but THINK of them as each a separate part

This may be a poor example. What I'm trying to get at is wherever the drop changes "a lot" is right where the problem is. As you move one way or the other with your probe along that path, wherever the drop "is" will change the reading
Click to expand...

20181008_204204.jpg


20181008_221224.jpg
 
So I am now questioning my sanity here ffs. Do the above test results indicate a drop in switch? If so then both switches are bad?
 
Ok I have read and been told with everything hooked up (except distributor leads) and key on that when tapping harness side of distributor connector to ground there should be a spark??
Well there is BUT, I cant see it only HEAR it. If that makes sense. Coming from under distributor.
Is this right?
Thanks
 
Ok ran tests again.
12.50 V battery static
10.04V at coil +ve when cranking. Everything hooked up.
I then unhooked ECU and ballast resistor for tests below.
Ign 2(start)
0v key off
0v key on
10.80 V cranking.(1.70V drop??)
Then Ign1 side.
0v key off
11.53 key on
1mv when cranking.
Daves69 said:
Did you unplug the ECU when checking voltage at the disconnected ballast connectors?

How I check...…

1) Disconnect both sides of the ballast.
2) Disconnect the ECU plug.
3) Attach volt meter to Ign 2 ballast plug and ground.
Zero volts in "key off" position.
Battery voltage in "key start" position.
Zero volts in "key on" position.

4) Attach volt meter to Ign 1 ballast plug and ground.
Zero volts in "key off" position.
Zero volts in "key start" position.
Battery voltage in "key on" position.

How I see the system working.
Start circuit acts as a "hot" wire giving full battery to the positive side of the coil and "hotter" spark to the plugs on key start.
Run circuit is battery power reduced through the ballast resistor to not cause the coil overheat as it runs.
Click to expand...
 
Car tries to start when I release key. In start it just cranks.
A test I ran earlier gives 10.80 v at coil cranking.
This is a 1.70 Volt drop??
Notes from more of today's tests/results.
Thanks
Steve

20181012_205645.jpg
 
4spdragtop said:
Car tries to start when I release key. In start it just cranks.
A test I ran earlier gives 10.80 v at coil cranking.
This is a 1.70 Volt drop??
Notes from more of today's tests/results.
Thanks
Steve

View attachment 1715234756
Click to expand...
Steve. That all looks normal to me. I bet the voltage at battery when cranking is right around 11.

Is the problem that the engine won't start?

And this happen after changing from a positive regulator to the later negative type regulator, or is it seperate?
 
Well I haven't done this with a ignition like yours. But I have with my msd setup. Basically the same,interrupt power to the coil to create a spark. Result is a spark you can see and hear. From the coil wire to ground. Only hearing it from under the distributor,that's not right at all. Try it again with the coil wire close to ground away from the distributor. Distributor has nothing to do with this test. You are testing the ecu and the coil.
 
Test msd I use a paperclip to connect both sides of the lead to distributor. Purple wire to green or something like that. Pull paperclip and POW you gotta spark.
 
Not sure what cranking voltage is at battery. Difficult to do as doing this by myself for most part.
Yes problem now car wont start(in crank) but wants to fire when I release key back to run.
I had 69 and down charging system and issues arose(sudden power loss).
Tried to decipher problem and couldnt(square peg round hole).
Got a "good deal" on all new 70 up stuff.(alt & vr) and got new ecu, ballast resistor and coil.
Did the 70+ upgrades correctly I believe.
Now cant get it to start properly. It's now cooled down out and I'm working on it outside, so naturally harder to start(no choke). But I can tell it's trying to start in run not crank.
I took your earlier advice with doing an "as built" drawing and 99% sure this is how my underhood wiring is. See pic, sorry its hand drawn, I haven't had time to do it in MS Paint or another computer program.
Also pic of ign switch.
Thanks!

20181013_210634.jpg


20181013_210840.jpg
 
I'm not using the coil wire, I'm using the distributor lead, I will do the coil wire tap tomorrow. Should spark with key in run correct?
Thanks!
hangn0ut said:
Well I haven't done this with a ignition like yours. But I have with my msd setup. Basically the same,interrupt power to the coil to create a spark. Result is a spark you can see and hear. From the coil wire to ground. Only hearing it from under the distributor,that's not right at all. Try it again with the coil wire close to ground away from the distributor. Distributor has nothing to do with this test. You are testing the ecu and the coil.
Click to expand...
 
4spdragtop said:
Not sure what cranking voltage is at battery. Difficult to do as doing this by myself for most part.
Click to expand...
Doesn't matter. Your other test showed no problems in the wiring, we know its around 11 Volts and you can hear the starter is turning fast enough that it should start, that's close enough.
Your hand drawn diagram is fine. I could copy it, turn it 90 degrees and read it.

4spdragtop said:
Got a "good deal" on all new 70 up stuff.(alt & vr) and got new ecu, ballast resistor and coil.
Did the 70+ upgrades correctly I believe.
Now cant get it to start properly.
Click to expand...
Hard to know if this relates or not. Always a possibility it could be ECU. Less likely coil because you heard it fire off once on release from start.
It could be timing, it could be in the start switch, it could be fuel, or compression.
Lets eliminate the possibilities one at a time. Start with spark because electric is the area where things were changed.

The best and safest way to check for spark is one of these testers.
31GcuD3PIqL._SL500_AC_SS350_.jpg

Less than 10 USD and I'm sure you can find one at any autpo parts or small engine store.

Put it on a spark plug where you can see it while turning the start switch.

A slightly different test will be to put the key in run position. This one is only needed if the first test shows no spark.
Then take a jumper, or a screw driver with an insulated handle, and provide power from the battery to the start relay. In other words jump the main power from the stud to the terminal with the yellow wire. The solenoid will energize on and the starter will crank. The difference is the ignition will be getting power through the blue RUN wire instead of the brown START wire.
 
Ok so I hooked everything up and I tried to start it. Just cranks and cranks.....let off to run and it fired up. I didnt let it run long as I'm worried about frying something(lots of bare connections) while troubleshooting.
So now I move on checking for voltage drops. Everything hooked up, key OFF and headlights ON.
Battery direct at posts with HL on, 12.30V
1. Batt +ve to main junction at starter relay 9.6 mV. Seems minor.
2. Main junction at starter relay to red/blk splice(old ammeter hookups) 66.4mV. This one seems minor as well.
3. Red feed at key switch to same red/black splice(old ammeter hookups). 11.4mV. Minor or am I wrong??
4. Red/black old ammeter hookups to the HL switch(black/tracer) direct at switch.
This drop is a little larger, 95mV.
All these drops add to 182.4mV which =0.1824 volts.
In my opinion these are minor drops.
Thanks all.
 
Last edited:
So I redid some more tests
12.45 Battery v static
11.22 battery direct cranking.
With ecu and ballast resistor unhooked.
1. Ign2 terminal at ballast and batt -ve 1.3 mV, key OFF, key START 11.10 V, key RUN 0.6mV
2. IGN1 terminal at ballast resistor and batt -ve 2.3mV key OFF, key START 56mV, key RUN 11.77 V.

The start voltage seems good(11.10v) as compared to battery cranking (11.20v).
Could new ECU bu bad? I have another new one but dont wanna keep throwing parts at it.
Could I have messed up the wiring when I "upgraded" to 70 + VR and alt?
Thanks!
 
Testing coil +ve.
0 volts key OFF.
8.34 Volts key ON
10.34 Volts cranking....then it started NORMALLY while in CRANK position?
So a voltage fluctuation to coil??
I bought liquid electrical tape so going to put it on some of suspect wires under dash.
Neighbors are entertaining company outside so I'll liquid tape the wires for now.
Thanks all.

20181014_150238.jpg
 
That seems about correct. It should run with lower voltage. It should start with battery voltage.
Remember, once its running, the alternator will be providing system power closer to 14 Volts. The ballast resistor will bring it down from that 14 for the coil positive. How much lower will vary with current flow and temperature. You're in the ballpark.

Charge the battery, get it running. System voltage should be around 14. Maybe a little less at idle and a little more at fast idle.
Then check initial timing, because right now that's seems like a possible reason it didn't want to start easily.

This is a hydraulic lifter engine - stock 318 ?
 
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