'46 Will Not Re-Start

[JayChicago]

“Is it close enough?”

Definitely. Seems that the Echlin IC-9 is designed for 6volt, no resistor. You could use that. Or do as suggested above, wait for Skip’s coil.

Chances are the IC-7 is designed as an original equipment replacement, so will need a resistor. Skip’s coil will need a resistor too, if its an original coil.

[Mountain Dew]

I'm in no rush, I'll just wait to get my coil and distributor back from Skip. I'm going to need a resistor. Any recommendations on where I can get a "good" resistor from? I heard there's some junk out there. I guess I'll mount it on the coil like the picture Kube posted.

[1942deluxe]

Mountain Dew, did you check to see if there is a resistor next to the circuit breaker on the inside firewall? It should be located on the the driver's side inside firewall. Should be a wire coming from the voltage regulator running to it.

[Mountain Dew]

Originally Posted by 1942deluxe

Mountain Dew, did you check to see if there is a resistor next to the circuit breaker on the inside firewall? It should be located on the the driver's side inside firewall. Should be a wire coming from the voltage regulator running to it.

Thanks 42Deluxe! Yep it's there, right beside what I guess is a circuit breaker. I was looking more under the dash and not on the firewall. It looks like it is hooked up too. That might be my problem. I'm running a resister on a coil that doesn't require one.

I'm about to head out of town. I'll investigate more when I get back.

[1942deluxe]

Mountain Dew, you should be good to go when you get the coil back from Skip. If the resistor is in place and working you should be fine. When you get the coil back one terminal will be marked DIST and that wire will go from the coil to the distributor, the other terminal will be marked BATT. Hook your other wire up to that.

[Mountain Dew]

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I got the rebuilt coil and distributor back from Skip. I installed the coil and she fires off every time now! I'm not however getting the voltage reading that skips notes says I should have. On the battery side of the coil primary I'm getting 2.3 volts with the points closed. Skip says it should be around 4 volts. I'm getting 6.3 volts with the points open. I'll call and run this issue by him. I went ahead and installed the rebuilt distributor too.

Thanks to everybody for leading me in the right direction. I am slowly getting the bugs worked out of the ole girl.

[JayChicago]

Yeah, 2.3 volts is low. The resistor should drop about 3 volts. (it increases somewhat as the resistor heats up) Another couple tenths drop is to be expected thru the switch and wire connectors. But your battery voltage is 6.3, so you should see around 3.0 volts at the coil with engine stopped. I think you have some parasitic resistance. You could try to clean and tighten connections at the resistor and switch. Likely suspect is the switch itself....you can remove the working mechanism and clean the copper contacts. (not sure how easy that is to do on the '46)

Then with engine turning, the averaged measured voltage at the coil will jump up to around 4 volts, as Skip said. (with engine turning, points open 20% of the time, no current flow while points open, no voltage drop with no current, therefore full battery voltage seen 20% of the time)

[petehoovie]

Last year I had the same symptoms with the same voltage reading (2.3 volts at the coil) as Mountain Dew in my '34. The culprit turned out to be that the 87 year old resistor had changed value...

[1942deluxe]

Good news that you are back running!

[Mountain Dew]

Here' where I'm at with the low voltage at the coil...............

Voltage checks

Battery 6.3v
Switch In 6.3v
Switch Out 6.0v
Resistor In 5.2v*
Resistor Out 2.5v
Coil 2.3v

* I thought this voltage drop between the switch and the resistor was excessive so I doubled up the wire with a jumper and it was still only 5.3v at the resistor input. I also jumped the Input and output of the switch and still only had about 2.3v at the coil.

I called Skip and ran these results past him and he thinks its the resistor. I cleaned and checked the resistor, it's showing .8 ohms. I seen a post on here where a member named GM told how he fixed resistors. It seemed tedious. I found a NOS resistor on Ebay and I'll go that route.

[JayChicago]

Good troubleshooting!
I agree with you, something is not right about the voltage drop between switch out and resistor in. Should be no drop there. Is something else connected there that could be leaking some voltage to ground?
Yeah, try replacing the resistor, but I doubt that’s the problem.

Let us know what you find as you work thru this mystery.

[FlatTopFreddie]

Make sure you are getting GOOD ground. My 47 Mercury had similar symptoms, 6 volt, positive ground, battery grounds to body, down to chassis them body to engine. Try a direct ground wire from battery to engine … solved my start issue

[Mountain Dew]

UPDATE

I received the NOS resister today. It measured .8 ohm also. Installed it and still only getting around 2.8V at the coil.

I jumpered the original resistor inline straight to the battery then straight to the coil. No switch or car wiring involved. I still only got 2.8V at the coil. There's nothing left.

What resistor value are you guys showing? I read somewhere on here that the resistor should be the same resistance as the coil's primary. Mine is .8 ohm.

I also ran another ground straight from the battery to the bell housing. I tried calling Skip but got no answer. I guess he's started the weekend.

[JayChicago]

Originally Posted by Mountain Dew

UPDATE
I jumpered the original resistor inline straight to the battery then straight to the coil. No switch or car wiring involved. I still only got 2.8V at the coil. There's nothing left.

I don’t have an explanation for this. I don’t know what’s going on. Both your resistors seem right to me. Did the battery voltage drop while you have been working and testing in the garage? Have you taken readings with another voltmeter to confirm?

2.8 volts is real close. If you are getting good spark, I would consider it good enough.

[marko39]

I too changed resistors because of 2.8 instead of at least 3 volts at coil. It made no difference and car starts very quickly with the 2.8 volts. Have a skip rebuilt coil after my new ( made in china) coil bit the dust after 20min. At least it was good for target practice.

[Mountain Dew]

I have 6.3-6.45 at the battery. I've tried different volt meters and get the same readings. This beats me. It fires right up every time. I guess I'll take it out and road test it.

marko39.......Are you running your car with 2.8 volts at the coil? Have you had any issues?

[aussie merc]

have you tried checking total resistance between the resistor input and the coil as you may have a bad wire or connection that is playing havoc with the voltage drop and often the longer you run the worst they get yet when checked cold show little or no extra resistance chasing them can be an absolute pain i always run them for at least 20 mins before checking trying to replicate how they work going down the road

[Mountain Dew]

I used a jumper to go from the battery to the resistor and a jumper to go from the other side of the resistor to the coil. Total resistance was still only .8 ohm and still getting about 2.8v at the coil.

[Mountain Dew]

I've been driving it around town and it is doing fine. I spoke with Skip and it's still a puzzle. I'll keep tabs on it but I'm not going to let it stop me from driving. I have other bugs to work out of it. Thanks for all the responses.

[JayChicago]

Good to hear its running well.

Thanks for posting the follow up. Always good for the rest of us to learn if/how a problem got resolved.