Electrical woes :-(

[EvilBob]

I'm at my wit's end with the electrical system on my poor '71. Pretty much all of my posts on this forum have been related to it in one way or another. I just want it to run again so I can take the top off and drive it a little while the weather is nice. No more deep water, I promise

Anyway, the starter solenoid was bad, I replaced that. The battery cables were all nasty/corroded so I replaced them. The alternator was bad, so I replaced it. All this went bad mind you at once, after a little swim. I don't know what or how, but a little dip in a water hole has completely killed everything electrical on this whole truck. It wasn't really even that deep :whoops:

I can wrench all day long, but I'm no electrician, so I gave up and took it to a local automotive electrical diagnosis expert. He played with it for a little bit and decided the ignitor is bad, but he can't find a replacement. Like I said, it's a '71, but the previous owner swapped the drivetrain for that of a '78 or '79 (2F, 4speed, etc) so I would assume this makes it the full electric ignition. Where does one locate a new ignitor or a suitable replacement? The electrical guy says that if it's possible it might be cheaper and easier to just put an old school points/condenser ignition on it. Is this possible/easy? Like I said, I just want the poor thing to run again.

Also, despite my lack of electrical knowledge, I'm not entirely convinced that this is the only problem. In my time tinkering with it I found that although I get a voltage drop at the battery when I turn the key, I don't think I really have any juice in the system. The headlights and stereo do not work, with fully charged batteries and the key in or out, on or off. I recall reading about a constant power connection something or other from the fuse box to the starter maybe? that would power these items. Would this prevent the beast from starting? Any other ideas?

The noob says thanks.

 

[Von Chaos]

Do you have power to the fuse box?

 

[lostmarbles]

I pressume a 71 has "fusible links" in the wiring just like my 79.

Check them................................

Deleted the rest of this post because this pressumption is WRONG (See Steve's post = #6)

 

[Pin_Head]

It is possible to put a points type ignition and distributor in. Just make sure you have oil pressure before you run it.

Pictures of the distributor and ignitor would help. I presume you checked it for a spark?

You always get a voltage drop across the battery when you turn the key to start. You shouldn't if you only turn it to on. If you get a voltage drop at the battery with the key in the "on" position, then maybe
the battery post connections are corroded.

If the headlights and all the other chassis power doesn't work, then there is a major problem with the main power feed from the battery. This would also explain why it won't start as there may be no power to the coil. (did you check?)

On a 71, the main power wire takes off from the starter motor battery cable as a white wire that goes to the amp meter and then to the key switch. From there it branches off in two lines to the fuse block as constant and key on power. Turn the key on and all the other switches and check for voltage at the fuse block. If no voltage, work back to the key, amp meter, starter until you find voltage. There will be a bad connection somewhere after the point you find the voltage.

 

[D'Animal]

Check your grounds.

You should have a black with a yellow strip ground wire;

Engine to Frame on the USA passenger side of the front engine mount.

Engine to Body located about cylinder #6 on the valve inspection cover to the body.

Some I have worked on also have a wire from the body to the T-Case.

When doing any wiring, always start and make sure you have a good ground.

 

[Pin_Head]

I pressume a 71 has "fusible links" in the wiring just like my 79.

No they don't. The chassis power connects at the starter motor on a '71. This saved them 1 meter of wire.

 

[EvilBob]

Thanks for the replies guys

As I said I'm electrically incompetent so I did not check a lot of the things you mentioned like power to the fuse box. Didn't check spark either, but the truck never would turn over. I turn the key to "start" and the voltage drops at the battery but nothing else happens. The starter doesn't engage, the solenoid doesn't click, and I don't hear any fuel pumping or anything. I assumed I should try to get it to at least turn over before it would need any spark.

The problem now, is that the truck is sitting at the auto electric shop. I am hesitant to bring it back home, because even if it has other problems besides the ignitor, I would trust this guy to diagnose them and fix them more than I would myself. And I was hoping I would be able to drive it home, and avoid paying a towing bill both ways

Also, I am unsure of how much of the electrical system is '71, how much is '79, and how much is custom. Here is a pic of the dual battery setup that was on it when I got it. This pic is pre-new battery cables. The nasty looking ones in the pic have been replaced. You can also see the ignitor/coil and the top of the distributor. I took the fender off at some point for easier access to all of this

 

[dargreg]

I hope the ground wire to the engine has been replaced its much to small, The power wire to your starter (the small red one) doesnt look good either.D'Animal has it covered TLCs love their grounds LOTS of them.

 

[Pin_Head]

The wiring is not stock, so it is hard to know where the power for the chassis comes from. If the starter motor won't crank the engine, then either the starter is bad or the engine is frozen. Can you turn the engine by hand. If so, jump across the two large lugs on the starter motor with a screw driver and see if the starter motor will turn.


It looks like there might be some kind on non-stock ignitor on the coil. More pictures and better pictures might help.

 

[D'Animal]

Doesn't the coil and ignitor need to be grounded? I know in the FJ60 series 2F you can blow it if you crank it and not have it grounded, as per FSM and Gas A Lot.

 

[EvilBob]

The wiring is not stock, so it is hard to know where the power for the chassis comes from. If the starter motor won't crank the engine, then either the starter is bad or the engine is frozen. Can you turn the engine by hand. If so, jump across the two large lugs on the starter motor with a screw driver and see if the starter motor will turn.


It looks like there might be some kind on non-stock ignitor on the coil. More pictures and better pictures might help.

The starter does turn, jumping the two lugs like you said will get it to do so, but turning the key will not. I took the starter off and had it tested at an auto parts place and it checked out as good. Like I said I get a voltage drop at the battery, but then nothing else when I turn the key. Like I'm not getting power to anywhere from the batteries?

The thing ran like a top even after it got a little wet. The engine was semi-recently rebuilt and served as the previous owner's daily driver until starting a business forced him to sell it. I drove it ~30 miles back to the house after playing out in the woods all day. It started right up a day or two later when I pulled it into the garage for some fresh fluids and stuff. Unfortunately it hasn't run since then

I'm not sure about the ignitor, I'm pretty sure it has a Toyota part number on it, although it does look a little bit newer than the coil, so who knows.

If I were to decide to get a new ignitor, where would I look? They're expensive, right?

Would it be silly to let the electrical shop guy convert it back to a points style ignition, and let him sorta tinker with it to get it running? Unless there's some huge detriment to performance or driveability/reliability then I wouldn't mind. I just want to be able to drive it some.

I could probably drop by the electric place and take a few more pictures if they would help, unfortunately I think that one is the best I have.

 

[Pin_Head]

Does the starter motor run when you jump between the battery cable and the spade lug of the solenoid? If so, then you have no power from the switch. Is there any voltage at the switch or the fuse box?

The ignitor needs to be grounded. It is the job of the ignitor to ground the coil through the - lug. This is the only ground that the coil needs

 

[EvilBob]

Doesn't the coil and ignitor need to be grounded? I know in the FJ60 series 2F you can blow it if you crank it and not have it grounded, as per FSM and Gas A Lot.

I wondered this myself, so I was sticking it up on the firewall when I was attempting to start it. After actually inspecting the combo, though, it appears to be just a bracket that mounts it to the fender, something that wouldn't actually ground it. I may be completely wrong though

 

[EvilBob]

The ignitor needs to be grounded. It is the job of the ignitor to ground the coil through the - lug. This is the only ground that the coil needs

When I was first attempting to start it I would ground the ingnitor on the firewall. The last few times I was not, though, sort of assuming it didn't need it. This wouldn't have prevented the engine from even turning over though, would it? Meaning there is still another issue somewhere. Obviously, once the engine turns over, I will need to have the ignitor grounded to fire the engine, but the ingnitor being grounded isn't going to keep it from turning, right?

 

[dargreg]

May be your amp gauge is blown if so you wont get power to your fuse block or switch on the 72s anyway. You must have power to the + side of the amp gauge and out .

 

[Pin_Head]

This wouldn't have prevented the engine from even turning over though, would it? ?

No. It would prevent it from delivering a spark.

Fix the starter motor problem first. Do you have power at the fuse block and the ignition switch? If the switch has no power, it can't operate the starter motor solenoid.

Focus: Does the starter motor run when you jump between the battery cable and the spade lug of the solenoid? If so, then you have no power from the switch. Is there any voltage at the switch or the fuse box?

 

[joeyg1973]

Time for a Painless wiring harness.

 

[EvilBob]

Time for a Painless wiring harness.

Yeah, maybe . . . think I could incorporate my dual batteries?

 

[dargreg]

Try and find a donar wire harness,Painless aint so painless