8n quit-still no spark

DavidIowa

New User
I sent out a message on December 24 as follows: early 1948 8n, front mount distributor, 12 volt, electronic ignition. Plowed 10" of snow without problems for 2 hrs. Next day went out to touch up lane, worked fine for 3 passes. Suddenly one very loud backfire, seemed to come from right side of engine, and engine stopped. Restarted and ran for 2-3 seconds and stopped. Gas line and filters OK. Plenty of juice. Starter turns engine easily but no spark. Pulled and pushed into garage. 2 days later still nothing. Where do I start? Thanks.

Common responses were related to snow in distributor. I pulled it, took it inside to dry out, let is set for several days. Today I reinstalled it and there is absolutely no spark. I used a meter between the coil terminal and ground and got 5 volts. Seems a little high. The only resistor in the line is the ballast resistor. It seems like it might be the coil or the electronic ignition module. Any more suggestions on trouble shooting? Thanks
 
Did you do the EI conversion? Still got the points around somewhere? I can't think of any other way to test the front mount square coil.
 
1, call the ei maker if you bought it

2. put breaker contatcs plate back in and test.

3, got a spare coil?

4, the 5v.. did you bump engine and recheck?

post back
 
Loud back fie sounds like you blew the electronic ignition system as in let the smoke out of it. Same thing happens to a point system if the points slip with the engine running and you can/will get a back fire and loose spark so your E.I. stands a good chance of being toast
 
First do as wrenchtech said, and then if no blinking, proceed as follows:
Pertrinix_neg_gnd_tst.jpg
 
I put a test lamp between the coil terminal and ground. Cranking dimmed the lamp but it didn"t make it flash. Does this mean a new coil? Thanks for the help in working through this problem.
 
(quoted from post at 13:20:11 12/31/12) I put a test lamp between the coil terminal and ground. Cranking dimmed the lamp but it didn"t make it flash. Does this mean a new coil? Thanks for the help in working through this problem.
t should be flashing dim/bright/dim/bright in unison with each cylinders firing time. Never completely dark.
If just dimming due to starter load lowering battery voltage, then either coil spring-like pig tail not making good connection to concave screw in distributor or pig tale shorted to distributor body or EI not switching. Check coil seating & connection, then do EI test that I described/pictured.
 

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