proper coil/distributor combination for '39
 

A friend is helping a friend with his '39 deluxe 85 HP that is hard to start when warm. What is the proper ballast, coil, distributor combination for that year? should it have the ballast under the dash on the firewall with the coil mounted on the distributor?

Re: proper coil/distributor combination for '39
 

If it has the original distributor, it would be a "Helmet" type with the coil mounted on top with 2 screws. The condenser is also mounted with the distributor. The ballast resistor is under the dash.
For reliability, I would have the coil redone by Skip Haney in Florida, and maybe get a new condenser. The ballast seldom causes any problem

Re: proper coil/distributor combination for '39
 

Here is the wiring diagram if that help you any. The original coil was mounded on the distributer. There was a resister unit mounted under the dash.

The resistor assy is 18 12250 and used 32-48.

Re: proper coil/distributor combination for '39
 

Yes, '39 would have a resistor on the firewall behind the dash, '37-'41 helmet type distributor with a two screw mounted coil on top of the distributor. The distributors in those years would have used some different advance weights. Not sure what advance curve would be stock for '39, but the '41 advance curve may have been considered to be the best.

Re: proper coil/distributor combination for '39
 

And send the coil to Skip Haney for a rebuild. It will save lots of headaches down the road.

Re: proper coil/distributor combination for '39
 

Thank you 40cpe for posting the question and thanks for the responses. As mentioned above, I'm working on my friend's 39 Deluxe, he wants it rewired staying with the 6v system. The problem he is having in addition to the headlights barely working is that once driven, the engine will not start while hot. You have to let it cool off before it will generate spark. Someone in the past took off the original coil because there isn't one on the distributor anymore; it's been replaced by a cylindrical coil which has been mounted between the carb and fuel pump.

Re: proper coil/distributor combination for '39
 

If it is a spark issue with heat soak it could well be the coil or the condenser.

Re: proper coil/distributor combination for '39
 

There is a condenser on top of the distributor that I assume is supposed to be there?? How would I check to determine if the coil or condenser is bad when hot?

Re: proper coil/distributor combination for '39
 

I would probably rewire the car first, then see where you're at with the starting problem. Could be related.

Re: proper coil/distributor combination for '39
 

Good point. Thanks

Re: proper coil/distributor combination for '39
 

Does anyone know the resistance of the stock coil on a '39?

And what should the voltage be at the coil with the resistor warm and points closed?

Re: proper coil/distributor combination for '39
 

The stock 6 volt coil is .6-.8 ohms primary resisitance........on the average car you will see 3.5 volts or more at the coil ......

Assuming the resistances are the same (close to equal) each would drop the voltage 3 volts with engine not running . A running engine will supply a 7-7.2 volt feed and then they would drop 3.6 volts etc......
Pretty amazing that the coil can and does produce spark at 3 volts supply but they do very well ......
assuming everything else in the circuit is perfect....

Re: proper coil/distributor combination for '39
 

Bubba, Thanks for the info

Re: proper coil/distributor combination for '39
 

I ohmed the coil and resistor last night, both of them cold. The coil measured 1.6-1.7 ohms of resistance between the posts and the resistor under the dash measured .5 ohms. I did notice that one of the terminal nuts on the resistor was loose so I tightened it. It was late at night so I didn't drive the car in order to test the ohms of the coil and resistor when hot.

Also, here are a couple of pics of the distributor and coil. I'm new to flatheads so please forgive my ignorance.

http://www.fordbarn.com/forum/pictur...ictureid=30325

http://www.fordbarn.com/forum/pictur...ictureid=30326

Re: proper coil/distributor combination for '39
 

40,
Is it possible the tube coil has an internal resistor in it ? Usually somewhere
on the body of the coil there is a note stating this.
Charlie ny

Re: proper coil/distributor combination for '39
 

Coil is incorrect for the 6 volt system.....................

Re: proper coil/distributor combination for '39
 

Also the coil is mounted where it will get a lot of engine heat. Should be mounted off to side.

Re: proper coil/distributor combination for '39
 

Thank you Bubba. I'll be looking for a correct coil and I assume a factory one would be the best. Do you sell them or should I just buy one from a restoration parts supplier?

Re: proper coil/distributor combination for '39
 

Mount the coil like Ford did in 52-53 standing up beside the Generator .

Re: proper coil/distributor combination for '39
 

I think your looking at low compression Good Look