O.K., I searched the archives and found lots of posts that were informative but didn't solve my issue. Just bought a 41 sedan a few weeks ago with a V8 from a 39 truck (I was told). took it out for the 1st long drive and it crapped out @ a stop sign. Let it cool for a while and it starts up again (but runs rough). Ended coming home on a flat bed. The next day my buddy follows me around the neighborhood to see if we can repeat the resaults and diagnose. After 30 minutes of running the same thing happens. My buddy checks the ignition wire going to the coil with his multimeter and gets like 2.9 volts. So we ran a temporary wire straight from the battery to the coil and it starts right up. After we get it back home I decide to let it cool off while I have some lunch. Go back out later...no spark. I figured the previous events were symptoms of a weak coil and it had at least lasted long enough to get me home. So I buy a new coil, condenser, and ignition resistor. Put it all together and.... Nothing! So, did I burn something up when we ran the hot wire from the battery to the coil (like the points)? How much voltage should be coming from the switch to the coil(I assume less than 6V due to the resister). am I missing something? this is my 1st flathead so I'm still learning, but any help is appreciated. Roger
3 volt to stock coils. It does depend on the coil but most early flatheads are 3v. My first thought from the first part of your question was a coil issue. Coil gets warm, then fails. Fairly common with old coils. Now it can be a number of things. What condenser you using? Sometime they can be bad right out of the box. Points could be burned out too. Hope this get the thread rolling for you.
Connect a test lamp or meter to the pos. and neg. on the coil crank the car the light should go on and off (or V / no V on meter)as the points open and close. If not then file or replace your points.
Thanks for the input guys. The condenser came from NAPA, an Echlin (FA49); Certainly wouldn't be the 1st time that I've got a brand new broken part. The points seem to be the next thing to check. Gonna check the coil too now that I know how (Thanks J scow).
I don,t know what coil you bought but I,d get one like a 1950 Ford uses round and no resister needed.
A few things for you. 1) I looked through your picts and it looks like your running the divers helmet coil. If you are keeping it, look up "Skip" Haney. He can rebuild your coil and it will be better then new. 2) There are also adapters out there that can convert you divers to a round later coil. To me, after you buy the adapter and a new coil you have pretty much spent as much as a rebuild from skip. 3) You can change out the divers and go with a crab style dizzy. You will need the adapter plate to convert the 3bolt dizzy to a 2 bolt. Crabs can be easier to work on. The napa condenser you bought is the correct one for 37-41. This is a good read on condensors. http://www.fordbarn.com/forum/showthread.php?p=264669 Best of luck!
For that helmet coil you will need a resistor. It'll work for a while but over time you will fry that coil and burn out your points faster.
Maybe you 'shouldn't', but you do. Run that diver's helmet on 6V and you'll boil the oil out of the seams. (if you don't fry both sets of points first) We shouldn't need to be skeptical of the State of the Union speeches, either.
I've got to ask: are the points adjusted correctly and are they in good condition? Over the years I've probably seen more points that were either burned or were not adjusted correctly causing problems over the years on just worked on cars than anything else.
Coil is first suspect, especially if car runs fine for a few minutes after cold start. Voltage is about right, will be higher before resistor warms up. On distributors that have sat for a while, sometimes the long spring on a point will fail...if it grounds, you stop, if it doesn't ground it can make a 10 degree shift in timing... Coil is a real issue...old ones almost all have your exact problem, many imported repros are garbage, rebuilt is excellent but expensive. Cheap way out is to get adaptor plate and run a modernish coil. Buy good brand deluxe version...there are plenty of crap brand new coils available nowadays too!
thanks for all of the info guys! Been down with the flu for a few days so I haven't done anything to it since installing the new coil, condenser and resistor. Gonna check the points next. A couple of old timers have told me it's easier to work on the points with the distributor out of the car; not sure if I'm ready to try that yet(I'm a lot more confident @ body work than mechanics).
Saxon- thanks for the link. what a cool site! Gonna have to add Fordbarn to my faves list. wonder if they already have a bondojunkie registered over there?
Had sorta the same problem and since I live so far away from the parts store I bought a coil and a new condenser, put them on, problem solved
If you get in touch with Bubbas in Indy, he has what you need and lots of info. I had coil problems, like they would last 3 months and die, NAPA would replace them and 3 months the coil towers would crack and die. Bubbas sold me a coil and said it would be the last coil I would ever need for my 29. So far He's right, and its been better then a year. Iceman
Bubba is an ignition master. bondojunkie, it's a great place for original ford and flathead information. Not that anyone there is ignorant to flathead hopups.
Epilogue: just wanted to say thanks again to everyone that helped out and to bring a little closure to this post. I ended up replacing the resister, coil, 2 condensers, the points and the rotor; and still never got any spark! And just to make sure it wasn't just me, I had several buddies who are way sharper than me to look @ it and they were stumped (including my uncle who worked as a Ford Mechanic back in the 50's before becoming a science teacher). The point is now moot as the '41 is now on it's way to Detroit in the care of a gentleman who had more disposable income than I did attachment to the car. He promised if he unraveled the mystery he would let me know what I had missed. If he does I'll pass it along to y'all. Meanwhile I am flush with cash and Billetproof Florida is only weeks away...
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