need help 71 fj40 just died on me

[sneek]

Here's what happened. Drove around town all day and it ran great and on the way home the engine just died . It did not spit and sputter or run rough , it just died as if I had turned the key to the off position.
I have fuel going into the carb. Motor turns over fine . I feel like the problem is with the ignition. It has a pertronix flame thrower coil on it . I put a new coil in it and still wouldn't start. I am going to see if I have spark going to the plugs today when I get off work.
One guestions I have is if there is no spark at the plugs or the the plug wire coming off the coil to the center of the distributor what would be the next thing to look at.
If I have spark coming from the coil to the dist. Cap what would I replace inside/under the cap. Of the distributor cap. Any help would appreciated. Thanks ,Justin.

 

[John Smith]

Here's what happened. Drove around town all day and it ran great and on the way home the engine just died . It did not spit and sputter or run rough , it just died as if I had turned the key to the off position.
I have fuel going into the carb. Motor turns over fine . I feel like the problem is with the ignition. It has a pertronix flame thrower coil on it . I put a new coil in it and still wouldn't start. I am going to see if I have spark going to the plugs today when I get off work.
One guestions I have is if there is no spark at the plugs or the the plug wire coming off the coil to the center of the distributor what would be the next thing to look at.
If I have spark coming from the coil to the dist. Cap what would I replace inside/under the cap. Of the distributor cap. Any help would appreciated. Thanks ,Justin.

Energize the coil directly from the battery and see if it starts. If so, the problem lies somewhere in the ignition circuit.

 

[ColonelMustardFJ40]

I have had this happen to me and it was the spring band on the set of points. It had broken in two because of rust due to moisture getting into my distributor as a result of a water crossing in the past. Replaced the points and was on my way, provided you still have points.

 

[skidplate]

I had a bad connection on my fusible link that would cause my engine to just die . I replaced the link....no more problems. Sounds like you are on the right track. Good luck.

 

[My wife said no FJ!]

Happened to me in my CJ7...it was due to a loose ground wire.

 

[splib]

Just happened to my brother on his '78. Turned out to be corrosion on the battery posts.

 

[alan m]

If it turns over but wont start, the problem has to be that you are not getting any spark to the plugs.
If the coil is ok, inspect the rotor and cap for signs of arcing and pitting.
You can also pull one of the plugs and see if it sparks when turning the engine over, be sure to ground the base first.
That will tell you if your rotor, cap and points are good.
Good Luck
Alan

 

[Pulso]

I had very similar symptoms with my '71 the other day and it turned out to be a stuck float. I thought I had fuel going into the carb too. Take off your air cleaner, pour a little gas in your carb and see if it starts.

 

[igotta40]

"Energize the coil directly from the battery and see if it starts. If so, the problem lies somewhere in the ignition circuit."

And/or run a wire from the distributor body (-) to the coil (-). I had that wire break inside the insulation, talk about a hard one to diagnose!

 

[sneek]

Ok I forgot to mention it has a pertronix ignition. I suspect the ignitor is bad . I have a new set of points and condenser and a new coil that came with the FJ40 when I bought it . How hard would it be to convert back to points . It will be a few weeks until I get a new ignitor . I have everything I need to go back to points for now but not sure how much trouble it is . Thanks for all the help..

 

[edwjmcgrath]

Before you go spending money on a new ignitor, you should do a little diagnosis.
I'd bet that it is something else electrical.
Do you have power going to the coil when the ignition is on? A test for that was suggested.
Ignition switches on these rigs fail all of the time, it could be that.
Before you buy a new pertronix, I'd put the points in. 20 minute job. If it runs on points and not pertronix THEN it it might be the ignitor.

 

[sneek]

Yes I have voltage at the coil with the key in the on position. The truck turns over so I would say the ignition is good