Weird Starting Issue (1 Viewer)

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Mar 26, 2015
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Rig: 1978 FJ40 2F

Lately my FJ40 has not been starting right up like it has in the past. Usually the engine turns over a couple of times and she fires right up. Lately, however, it takes a substantial number of turns before firing up. 10 turns then I turn the ignition off....10 more turns...same thing. Pump the gas a bit and no fire. Pump one more time around 10 ish turns and the engine finally turns over. Lately, I've been going through this sequence betwee 4-6 time before the engine turns over. Once I have her running and she warms up everything seems to be fine. The engine will turn over just fine the remainder of the day.

If I let her sit for a couple of days without driving is when this start up issue occurs.

Yesterday, after the 5th attempt to turn the engine over I turned the ignition (5th time) and there was nothing. No turn over at all. Nothing fired. Just quiet. Turned it again and it fired right up. Really odd.

Anyone have any ideas what the culprit might be? I have an OEM mechanical fuel pump too FWIW and a Weber 38/38.

EDIT: The engine is not sluggish during turn over.
 
  1. defective ignition switch
  2. Filthy battery terminals/weak battery
  3. Missing wire that gives extra voltage on starting
  4. Poo-poo fuel filter
  5. Etc. etc.
 
  1. defective ignition switch
  2. Filthy battery terminals/weak battery
  3. Missing wire that gives extra voltage on starting
  4. Poo-poo fuel filter
  5. Etc. etc.

Maybe an ignition switch but how can I test to see? My battery is only a year old and the terminals are spotless. No missing wires and I run two fuel filters and both are clear and clean.
 
Good through Tuning 101 stuff.. Plugs, wires, by rotor, cap, etc

I just replaced all plugs, wires, new dizzy, etc. about a year ago. I pulled plugs earlier and they look the way they should.
 
not sure how to test the ignition switch but very similar symptoms to when my ignition switch was going. I just went for the switch as most everything else was pretty fresh.
 
Sitting for a couple days the gas in the bowl is evaporating or siphoning off.
From my experience just about every carburetor'd car has that problem.

The 350 in my Cruiser will fire right up with barely a turn of the switch but sit for a few days and I have to prime the carb or it will crank but not fire.

If it has set a day or two or more I turn the key with foot off the gas peddle and count to ten while cranking then turn off key, pump gas peddle three times and the engine usually starts right up when I turn to start.
If it does not start try the sequence again.
If still no fire then most likely there are other issues.
Flooding is likely if done too many times in a row.

This is a trick my dad showed me when I was a kid so that tells me dry bowl after several days is nothing new and the method has worked on just about every carburetor car I have messed with.

You stated that your vehicle starts and runs fine after the first start up of the day so if everything is in good working order the method I use might help.
 
For a quick test of the ignition switch you could hook a temporary test light to the + side of the coil that you can see from the driver’s seat.
I mounted an led pilot light permanently under the hood when I was having all my Pertronix issues. I can see it while cranking with the hood up or when I’m under the hood. Helps with quick diagnostics if having starting issues without breaking out the meter.
 
fuel level in carb had no effect on the issue when my ignition switch was dying... would just crank and crank and not fire and would only happen in the morning too as far as I recall. See post #5 for a test from Pinhead...

 
If your ignition switch is original, just replace it. Cheap insurance against the next most likely scenario: starter engaging while engine is running!o_O
 
There seems to be one thing that confuses some not really familiar with what the key switch is actually doing during starting.
Everyone knows the key switch has 4 positions Acc, Off, Run and Start. What throws people off is when a key switch is starting to fail, sometimes it's the RUN contacts that feed power to the coil/igniter that go out or become intermittent. This means the truck will crank over fine as the START contacts are working, but the coil/igniter is not getting power due to eroded RUN contacts. The idea of adding a light to the +side of the coil is a good one. It allows one to easily see if the coil is getting power during the cranking stage.

Maybe I should build a new trouble shooting kit for the electrically challenged....
 
There seems to be one thing that confuses some not really familiar with what the key switch is actually doing during starting.
Everyone knows the key switch has 4 positions Acc, Off, Run and Start. What throws people off is when a key switch is starting to fail, sometimes it's the RUN contacts that feed power to the coil/igniter that go out or become intermittent. This means the truck will crank over fine as the START contacts are working, but the coil/igniter is not getting power due to eroded RUN contacts. The idea of adding a light to the +side of the coil is a good one. It allows one to easily see if the coil is getting power during the cranking stage.

Maybe I should build a new trouble shooting kit for the electrically challenged....

I'm familiar with what my 4 positions SHOULD be doing but I just noticed today that the engine would turn over when I had it in the ON position before I even made it to the START position. Then on a separate attempt it would not turn over until I had it fully in the START position.

If it is turning over in the ON position what is that telling you? I have a bad ignition switch or maybe the ON and START wires on the back of the ignition switch are touching causing it to start the engine in either mode?

BTW...here is my ignition switch
1911505
 

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