Cylinder #1 not firing at idle 2F (1 Viewer)

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Jul 20, 2015
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Alright so I’m at the end of my knowledge here and what I can find by google.

69 FJ40 with later model 2F components all Frankensteined together with the”semi electronic” vacuum advance distributor

Noticed about a week ago that it was ideling rough but running fine otherwise. Checked all the usual things like fuel/air and sprayed around the carb an intake with starter fluid to see if that did anything; nothing. Ok.

Pulled all the plugs and they looked fine. Adjusted timing and thought that might have gotten me somewhere maybe it slipped timing. Next day back to the same thing ideling rough. Go to check timing again and notice my timing light isn’t lighting up on #1 cyl. I turn up the idle just enough to the point where it starts running smooth again and what do you know my timing light works again. So I try swapping plugs and wires around and nothing can get #1 to fire at an idle. I figure maybe it’s a time for a new cap and rotor.

Fast forward to today and the cap and rotor made no difference. Still not firing on #1 at idle.Now I don’t know a ton about points but I know a shop replaced them about 5,000 miles ago and I’m not sure why that would affect only one cylinder only at idle. Also here’s the odd part if I grab the distributor (not the cap) and pull down or push on it in any way #1 starts firing. So I’ve basically isolated it down to something in the main distributor. I don’t feel hardly any play at all in the thing but I don’t know how perfect it needs to be. Could it be my points somehow only messing up at idle? Is my distributor bad? I’m really at a loss here and all my more experienced mechanic friends are stumped too.
 
Verify the cam on the distributed shaft is actually opening the points to number 1...there are 6 lobes on the distributor shaft (under the rotor)...each lobe opens the points to fire the coil and associated plug. People forget, but you usually put a dab of grease on the lobes to keep the points from wearing down the lodes. It wasn’t uncommon in the days before electronic ignition, the lobes would wear and the points wouldn’t open.

I see a Pertronics in your future.....
 
Verify the cam on the distributed shaft is actually opening the points to number 1...there are 6 lobes on the distributor shaft (under the rotor)...each lobe opens the points to fire the coil and associated plug. People forget, but you usually put a dab of grease on the lobes to keep the points from wearing down the lodes. It wasn’t uncommon in the days before electronic ignition, the lobes would wear and the points wouldn’t open.

I see a Pertronics in your future.....
Tried a pertronix and for some reason it didn’t work. Then saw it said it wouldn’t work on my distributor.

looking right now it doesn’t look like the points are opening up at all and I’m gonna try to set them up to the right gap. But I’m confused because my truck doesn’t have an igniter or a condenser so nothing is really matching up to how my Hanes manual is describing it.
 
Like Mark Jennings was saying, the cam lobes wear out. Try a points gap a bit tighter than called for in the FSM, it will account for the wear to energize the coil a bit more between fires. If that works, then you might get a dwell meter to dial it in correctly.

My condenser on the '75 distributor was mounted on the breaker plate (internally), but externally on my Non-USA vac advance distributor. You might check to see.
 
This is the inside of my distributor.

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Do you know how to get the tang (driver end under the gear) of the distributor back in the block so the oil pump is engaged?
 
Do you know how to get the tang (driver end under the gear) of the distributor back in the block so the oil pump is engaged?
I just bought feeler gauges and no I didnt know if there was a specific way to get the distributor all the way down. That’s actually how I blew my old engine because I didn’t know about how that works :bang:
 
This is Totally @4Cruisers area of Expertise ......

OEM NipponDenso Parts Maker Ignition System Repair & Restore Specialist here on MUD ....... :)
 
You have to line up the oil pump slot to where you think the distributor will be oriented based on the twist of the gear (they are helical) as it engages with the camshaft.

And, it just so happens that 4Cruisers bailed me out of my distributor oil pump mistake, by setting me up with a replacement F out of his collection. It only takes a few minutes of a sleeping oil pump to spin or gall a crank bearing.
 
You have to line up the oil pump slot to where you think the distributor will be oriented based on the twist of the gear (they are helical) as it engages with the camshaft.

And, it just so happens that 4Cruisers bailed me out of my distributor oil pump mistake, by setting me up with a replacement F out of his collection. It only takes a few minutes of a sleeping oil pump to spin or gall a crank bearing.
Yeah when I made my mistake I thought my oil pressure gauge had just stopped working and had no idea the oil pump was dependent on the distributor. Figured that as long as the engine was turning the pump was turning haha..
 
Set the gap to .016 and put everything back together and then was reminded that my battery is dying for whatever reason. Figured that’s a good place to stop for the night. Guess I’ll jump it and see how it runs when I get back from work tomorrow.
 
Looks like a non-US points distributor to me. Two clues are the vacuum advancer and the points breaker plate. The non-US breaker plate has the easier to adjust points, with two hold down screws. The early US F engine distributor breaker plate had one hold down screw and an eccentric bolt that adjusted the gap as the points assembly rotated. BTW, it should have an internal condenser.Here';s the new style of breaker plate installed in an early distributor:

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Got it started up and set the timing. Cylinder #1 seems to be firing at any rpm along with the others now but I can still tell it’s ideling rough. It also has a flat spot when driving and the entire rev range seems like it’s tougher than before. Something is definitely off. And as a correction to my previous post I do have a condenser I just didn’t noticed it on the bottom of the distributor. I’m probably going to try replacing that since it’s cheap and see if that works but I’m running out of ideas here.
 
So that last issue ended up being a bad spark plug from dropping it on the ground; had no gap. Popped a new set in and it runs as good as ever. So for future reference I’m saying it was probably the points being set up completely wrong. When I got to them they literally had no gap and weren’t opening at all and now with the gap set right the distributor is a good 20-30 degrees off from before to achieve the same timing (7 degrees).
 

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