Builds Rescuing a Basket Case '72 FJ40

[diesellibrarian]

Well, last night i *did* try firing up the 40, and....wait for it.....it still runs like s***e. The carb rebuild had no appreciable effect.

I'm confident that the carb can be eliminated as the source of the poor running. So, my plan is to go back again and baseline timing and points. I'm also going to install a new condenser. If that fails, I'm going to pull the 2F big cap dizzy out of my FJ55 and swap it to the 40. My plan with the 55 is is build it as a 2FE, so I'll be using the spare 3FE distributor that I have laying around for that build. I gather that I will also need to swap over the side cover plate to the F engine?

A bit of a bummer but that's working on old trucks I guess.

 

[RevISK]

Well, last night i *did* try firing up the 40, and....wait for it.....it still runs like s***e. The carb rebuild had no appreciable effect.

I'm confident that the carb can be eliminated as the source of the poor running. So, my plan is to go back again and baseline timing and points. I'm also going to install a new condenser. If that fails, I'm going to pull the 2F big cap dizzy out of my FJ55 and swap it to the 40. My plan with the 55 is is build it as a 2FE, so I'll be using the spare 3FE distributor that I have laying around for that build. I gather that I will also need to swap over the side cover plate to the F engine?

A bit of a bummer but that's working on old trucks I guess.

I may have missed it, but have you gone through your plug wires?

 

[diesellibrarian]

I may have missed it, but have you gone through your plug wires?

I have visually inspected them and cleaned the contacts, but have not tested resistance. I guess I assumed they were ok since at one point the truck was idling quite nicely using these wires. But I should test them as a matter of due diligence.

 

[RevISK]

I have visually inspected them and cleaned the contacts, but have not tested resistance. I guess I assumed they were ok since at one point the truck was idling quite nicely using these wires. But I should test them as a matter of due diligence.

Last summer I swore I blew a head gasket the way the truck was running, turns out the #5 wire was disconnected. Ran like absolute garbage but ran.

Worth checking

 

[diesellibrarian]

Last summer I swore I blew a head gasket the way the truck was running, turns out the #5 wire was disconnected. Ran like absolute garbage but ran.

Worth checking

I did confirm that they were all connected and in the right order.

The thing is running as if its timing is messed up. If fires in fits and starts with the occasional backfire through the carb. I tried to static time it last night, which is something I have done many times on this truck and on my air cooled VWs. It wasn't responding in the way I expected, i.e. the test light would not shut off no matter the position of the distributor. I have not seen that before, and it makes me wonder if there's an internal grounding issue with the distributor, as current flow from the (-) side of the coil was not affected by the opening/closing of the points.

I believe it's the OG vacuum retard distributor, and there is definitely some play in the shaft, but I'm wondering if there's more going on - like some kind of ground fault between the retard plate and the body of the dizzy. This is new territory for me, but I'm sure I'll get it figured out. It's such a (theoretically) simple system!

 

[diesellibrarian]

I meant to add: it really reminds me of a time when my VW lost power over the course of a several-hour drive, to the point where it barely ran at all. The cause ended up being points that had slipped or worn so that there was little to no gap. That's how this truck is behaving, though I am sure the points are gapped correctly. That's why I also suspect a failed condenser.

 

[pb4ugo]

When you crank the engine with the cap and rotor removed, do you see the points opening and closing? If the points are working properly you can sometimes see a slight spark between the contacts. Is the wire going into the distributor grounding against the body of the distributor? Theres usually some sort insulated junction or material for protecting that wire. It could be the condenser, but i would think the test light would go out regardless if it was bad or not. Maybe disconnect the condenser and see if the test light goes out.

 

[bhsdriller]

backfire through carb is typically timing related

 

[RevISK]

Bummer. Was reaching for the low hanging fruit.

 

[FloridaLife]

Well, last night i *did* try firing up the 40, and....wait for it.....it still runs like s***e. The carb rebuild had no appreciable effect.

I'm confident that the carb can be eliminated as the source of the poor running. So, my plan is to go back again and baseline timing and points. I'm also going to install a new condenser. If that fails, I'm going to pull the 2F big cap dizzy out of my FJ55 and swap it to the 40. My plan with the 55 is is build it as a 2FE, so I'll be using the spare 3FE distributor that I have laying around for that build. I gather that I will also need to swap over the side cover plate to the F engine?

A bit of a bummer but that's working on old trucks I guess.

That's a good idea trying out the other dizzy.

The more I think back to dealing with the carb issues in my very first car (flooding, choking, vapor locking in the hot summer) and in my '69 Chevy pickup, the more I lean towards taking the carb off my 2F and running fuel injection. Especially if I can run my original air breather. I was looking at the Holley Sniper units, but they don't make a Sniper 2 for a 2 barrel setup. Someone in the "Best FJ40 Upgrade Ever" told me they bought this one and from the first time they turned the key after installing it, it has been perfect and they are super happy with it.

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[diesellibrarian]

Bummer. Was reaching for the low hanging fruit.

You and me both, brother.

 

[diesellibrarian]

That's a good idea trying out the other dizzy.

The more I think back to dealing with the carb issues in my very first car (flooding, choking, vapor locking in the hot summer) and in my '69 Chevy pickup, the more I lean towards taking the carb off my 2F and running fuel injection. Especially if I can run my original air breather. I was looking at the Holley Sniper units, but they don't make a Sniper 2 for a 2 barrel setup. Someone in the "Best FJ40 Upgrade Ever" told me they bought this one and from the first time they turned the key after installing it, it has been perfect and they are super happy with it.

#K247T - Toyota Land Cruiser TBI Conversion Kit

Marine City, MI – March 10, 2015 – For fans of the classic ’55-’91 Toyota Landcruiser, replacing the troublesome carburetion system with state of the art electronic fuel injection required a custom build that could end with questionable results. Enter Howell EFI who has come to the rescue with a...

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That's the dream right there, but I just can't throw any more money at this rig. But that is definitely the reason I'm looking at building the 2FE for my Pig. EFI just works, with none of this occult black magick carburetor voodoo.

Maybe that's my problem. Have I been sacrificing to the wrong gods?

 

[diesellibrarian]

backfire through carb is typically timing related

Agreed. That's why I'm going to go back and start from scratch at #1 TDC.

 

[diesellibrarian]

When you crank the engine with the cap and rotor removed, do you see the points opening and closing? If the points are working properly you can sometimes see a slight spark between the contacts. Is the wire going into the distributor grounding against the body of the distributor? Theres usually some sort insulated junction or material for protecting that wire. It could be the condenser, but i would think the test light would go out regardless if it was bad or not. Maybe disconnect the condenser and see if the test light goes out.

I didn't see nor hear any spark, which is weird. The wire to the condenser was isolated in some fashion with a rubber grommet that was clearly not original. Going to see if I can improve upon that when I install the new condenser.

I sure appreciate everyone's input on this! Y'all are so generous with your knowledge and experience.

 

[FloridaLife]

I didn't see nor hear any spark, which is weird. The wire to the condenser was isolated in some fashion with a rubber grommet that was clearly not original. Going to see if I can improve upon that when I install the new condenser.

I sure appreciate everyone's input on this! Y'all are so generous with your knowledge and experience.

I don't miss dealing with points and condensers either. Give me electronic ignition any day of the week.

 

[anothernz45]

If test light stays on all the time theres a short to ground somewhere, I'd check the terminal on the dizzy first. If its not ignition or carb related could it be cam timing? Havn't gone back thru your thread but 1 tooth out turns an engine into a pig. Tappet clearances ok?

 

[diesellibrarian]

If test light stays on all the time theres a short to ground somewhere, I'd check the terminal on the dizzy first. If its not ignition or carb related could it be cam timing? Havn't gone back thru your thread but 1 tooth out turns an engine into a pig. Tappet clearances ok?

I don’t think the timing gear is off. I have had it running nicely, so I know that it’s possible. I recently adjusted the valves, and then double-checked them. I’m sure they’re done correctly. I’ll be exploring timing and a possible ground short once I’m back from my vacation. Cheers.

 

[FloridaLife]

I don’t think the timing gear is off. I have had it running nicely, so I know that it’s possible. I recently adjusted the valves, and then double-checked them. I’m sure they’re done correctly. I’ll be exploring timing and a possible ground short once I’m back from my vacation. Cheers.

 

[diesellibrarian]

Have I finally solved the problem? I think I have…maybe? Checked the various things that people had mentioned over the past few days, and was still finding that the (-) terminal on the coil was always hot, no matter whether the points were open or closed. I decided to swap in the OTHER set of used points that I’d found in the glove box, and this second set seemed to work as designed. So I was able to static time the engine. Turned the key, and wouldn’t you know it, it fired instantly and settled immediately into a nice idle.



I’m pretty happy, but also mystified. The two sets of points look identical. There was no sign of damage on the set I removed. So what would cause one to short to ground? Has anyone seen this before?

 

[MatthewMcD]

Have I finally solved the problem? I think I have…maybe? Checked the various things that people had mentioned over the past few days, and was still finding that the (-) terminal on the coil was always hot, no matter whether the points were open or closed. I decided to swap in the OTHER set of used points that I’d found in the glove box, and this second set seemed to work as designed. So I was able to static time the engine. Turned the key, and wouldn’t you know it, it fired instantly and settled immediately into a nice idle.



I’m pretty happy, but also mystified. The two sets of points look identical. There was no sign of damage on the set I removed. So what would cause one to short to ground? Has anyone seen this before?

I suspect that there was a bad ground on the previous points installation. Is there a difference in insulation between the old ones and the new?