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Picked it up earlier started fine, ran some errands in town, started fine. Got home, parked in front of the house (blocking both house garages) and went to start it 30 minutes later, only for it to crank but not start. Checked battery voltage and tried again, quickly stopping when I noticed smoke.
The wire coming out the top of the alternator melted the insulation, it looks to also be spliced with one running to the large connector at the back of the engine and also burned some insulation off there. So at a minimum need to replace those wires, but also need to figure out what caused it (maybe a break in insulation shorted something).
It's very disheartening, between me starting it today and the place that worked on it, likely started fine at least 10 times. I've got no idea what caused the wire to melt like that, hoping to find a replacement, a lot of the wiring is very crusty and hacked together in many spots.
Feeling a little down over it, driving home it ran really nicely, needs suspension and all the weather stripping! But was fun driving it home, my youngest was ready to go for a ride and now has to wait. I'll post some pictures of the wiring tomorrow, hoping I can resolve it quickly.
I've seen this a ton of times and I hope this is your problem. "GROUND" Many times while cranking and you find smaller wires on the engine and most often coming from the alternator it's the engine block itself lacking a sufficient ground. The small wire on the alternator is acting as a ground and of course burning up because of it's size. I've seen people eliminate an engine ground in haste after pulling an engine often where it connects around a motor mount or from the back of the block to the body on some makes. It will search out a ground on its own causing headaches. Grounds are cheap and easy to attach to the block to body.
My buddy replaced his engine in his Corolla and it did the exact same thing yours is doing. I ran a jumper cable from the negative battery terminal to the block and it fixed it temporarily until we found the hanging ground that he missed that went from body around motor mount (which is rubber non-conductor) to the block. Good luck
The earlier model Toyota trucks with manual transmission were burning out the input shaft bearing on the tranny. Engineers found the metal bearing was serving as a ground for the transmission. When the bearing was spinning it would arc pitting the bearing. The fix was a ground strap directly to the battery to tranny. I ran a direct ground on my wife's from new to the battery.
You should check the connections at both ends of the ground straps also…
Where should the ground straps be located? The reason I ask, I don't see any. I see the battery to engine block ground, a small ground from the battery to the body next to the radiator, but no ground straps.
Looks like I'll need to locate a 4 wire alternator harness, the red wire is beyond repair as well as what I think is the wire to the choke. Those both melted all the insulation off, not sure if that's something available or if I'll have to try and make my own.
Those are the grounds. They need to be taken off, wire brushed or sand papered at the underside of the contact points to the block and frame and also scrape until you see bare metal on the block and frame.
Those are the grounds. They need to be taken off, wire brushed or sand papered at the underside of the contact points to the block and frame and also scrape until you see bare metal on the block and frame.
OK, good to know. I already removed the one at the engine block and cleaned it until the surface was good and shiny, the battery end is already pretty clean. I also already had removed the one going from the battery to the body next to the radiator, that wire was dry rotted and the insulation was cracked in multiple places, including missing entirely on a piece about 1/8" long (see picture below). Already bought wire to replace that with, so will get that installed later and then call some junk yards to see if I can find a new harness for the alternator.
One piece I am a little confused about, is that the top field wire on the alternator was spliced to a second wire. So, there is the red wire that runs through to the 4 pin plug at the back of the engine, the wire also goes to what I think, is the choke, not sure though. However, this is the wire that primarily burnt up, these 2 wires that are spliced together. When I get a replacement harness, or try to repair it myself, I am not sure if those should still be spliced together or if that was part of the problem.
Pictures below show the 2 wires circled red and where they are spliced together at the alternator.
That burned wire coming out of the choke junction box looks as if it may?? be the source.. The power doesn't run to the choke unless it's running to prevent the choke from opening up while sitting with the key on. Hence the junction box. I would disconnect the power source going to the choke junction box for now. The choke will just stay closed longer and won't open all the way. 6 cylinders are different they will operate fine without the electric choke assist. Replace the harness wires going to the alternator. It's kind of simple just replace what you cut out on that right bank. Note: Always have the battery disconnected while replacing wires. The cranking and no starting may be from the hot wire going to the coil getting smoked. Any way, the cut and splice is relatively easy. Try to color match the wires only because it will help in the future.
That burned wire coming out of the choke junction box looks as if it may?? be the source.. The power doesn't run to the choke unless it's running to prevent the choke from opening up while sitting with the key on. Hence the junction box. I would disconnect the power source going to the choke junction box for now. The choke will just stay closed longer and won't open all the way. 6 cylinders are different they will operate fine without the electric choke assist. Replace the harness wires going to the alternator. It's kind of simple just replace what you cut out on that right bank. Note: Always have the battery disconnected while replacing wires. The cranking and no starting may be from the hot wire going to the coil getting smoked. Any way, the cut and splice is relatively easy. Try to color match the wires only because it will help in the future.
That's great information, thanks. It seemed strange to me that the choke was spliced into the alternator like that. I'll feel better about having nothing spliced in like that and it should make a cleaner repair.
I started to depin the connector earlier, once I get that all complete I'll replace the wires with ideally same color and gauge and hope for a good outcome.
Battery always disconnected when working on electrical, I actually have had it disconnected since it smoked wire in case of a short.
Managed to get some of the smaller connectors de-pinned.
Hoping to get the rest of this one done later, although it is being problematic!
Then I need to see if any local parts store has any of those connectors and the correct crimping tool. Found a Dorman multi-pack with what looks to be the correct ones in there, but only has 2 of them per pack and 6 others that I don't need. Worst case I can
1. Cut the white plug off both ends, use some kind of crimps to crimp both sides together and use ring terminals on the alternator
2. Cut the white plug off both ends, buy a new plug and go that way.
I'd prefer option 2 if it comes to it, but hoping to be able to de-pin the connector fully and find new pins.
Got all the pins removed, but having struggles finding replacement connectors to fit the plug. While I think I have found a similar connector that should slot into the factory plugs, I can only find one for smaller gauge wiring (14-18ga) but 2 of the wires I have are 10ga, so they won't fit into the connector and I cannot find larger ones. I am sure they are out there, but searching through 1,000 different connectors is not fun.
Which might work nicely, but would be a bit of a squeeze for the 10AWG wire (2 x 10AWG, 1 x 14AWG is what I have), would also mean I need to order the correct crimp tool since I don't have one available.
Starting to wonder if I should simply cut that factory plug off and use butt connectors instead, if so, I could likely get it done much sooner since I believe I have everything I need to do here. The back of the alternator looks like the 2 that uses plugs, I can remove the plug and simply use a ring terminal under the nut instead, butt connectors to join both pieces of the harness together.
But, I worry about the reliability of such a connection. Any opinions? Sure would be nice to get the truck up and running this weekend (assuming I fixed the issue of course) but at the same time I don't want to rush and end up back at square one, or possibly worse.
Could just throw some wire nuts on like the PO and see what happens! haha
Last edited by Abcdefghii; 02-22-2024 at 06:18 AM.
The factory connectors are there for 2 reasons only. During assembly it's simple to plug and assemble. The same in reverse. If you were to pull the engine apart or remove disconnecting the connections is helpful. That being said.......splice and crimp works just as good and in some cases better making a direct pressed connection. I've certainly done my share of bypassing connectors. My wife's Jeep had an electrical connection under the seat that was fixed twice under warranty. The third time I ran a wire around the connector splicing and crimping that's worked out well for about 7 years.
Great, well it is wired up, then I ran out of time to see if the engine started. I am not 100% happy with the connector on the small red field wire, the original wire just did not seem to get a good bite with the crimp, actually went through 3. I had initially gone with a larger gauge wire because a piece coming out of the alternator was larger, but then at the other end was not going to work with the connector I had, so had to remove that and make a fresh one with smaller gauge. If it ends up starting and has fixed the issue, I think longer term I will strip the factory wiring back a little further and replace more of it with a quick disconnect of some kind. For now, the 3 butt connectors are exposed but will get wrapped in electrical tape as well if things go well.
Hoping I get time to try starting it later, but I might wait until I have an assistant to yank the negative battery cable real quick in case of any smoke.
Decided what is the worst that can happen (maybe not entirely sensible, it could have gone worse than some melted wire), hooked everything up, connected battery, took a deep breath. OK, good so far. Had my son stand next to the battery just in case, turned key and she fired up. Let it idle a few minutes and felt the wires from the alternator to see if they were getting warm to the touch, all good so far.
Had to get back to work, but will likely try starting it again later and if it starts then I can move it inside to install new shocks over the weekend, try to get the windows going up and down (manual), replace the wiper bushings, figure out why the shift indicator does not work, decide whether to start figuring out an HEI upgrade, determine if I really did use 1/4 tank of gas driving 8 miles (sure hope not) and so on.
So far at least though, I'll call this a win.
Last edited by Abcdefghii; 02-22-2024 at 01:35 PM.
Front and rear shocks replaced today, the old ones were completely shot. Not a terrible job other than the top nut on the front driver's side was a complete bear. Crescent wrench / vice grips on the flat just chewed it up, that to get a grinder and cut the top off. Ride obviously massively improved.
Started to look at the driver's window issue, I can't tell what the problem is. The crank turns fine, but doesn't appear to be engaging with the mechanism to move the window up and down.
Passengers side the crank doesn't even turn, but I want to get the driver's working first. Any ideas why the crank isn't engaging with the rest of the mechanism?
Tip on shock removal. With a 1/2 drive extension and socket over the shock nut bend the entire nut and threaded rod back and forth until it snaps off. Feels good doing it too!! LOL
As far as the window crank, the inner gear components I'm sure are spun clean making no gear-to-gear contact. I'm quite sure you'll need a window regulator.
As far as the window crank, the inner gear components I'm sure are spun clean making no gear-to-gear contact. I'm quite sure you'll need a window regulator.
At least it looks like regulators are available, just have to find some instruction on removing it. Both doors need all new weather stripping, so I may gather parts and replace both regulators and weather stripping at the same time.
The electric ones are difficult because of the spring load and getting your arm in there. I imagine your regulator is riveted in place. Just need to pop them off.
Yep, riveted in place. I found a video on YouTube and the guy was mentioning removing bolts, I'm looking at mine and thinking, there are no bolts here. Then found some posts here and there that they use rivets and those need to be drilled out. I might take the passengers door panel off later this week and see what is going on there, since one side cranks and does nothing, the other side does not crank or move the window. Likely both a similar problem though I am sure.
Small wins.... for those following along, in the 1st post I mentioned the wipers not working. Well, they are now. The motor was working, so sure enough it was the bushings that had failed. Actually, the only one that had failed completely was the one where the linkage attached to the motor. Manually moving one wiper arm they would both move, however, when I pulled the mechanism out I saw that one bushing was barely holding on.
Anyway, I replaced all of them, added some grease and reinstalled. Interestingly, 2 of the bushings I bought were a different material and so failed as soon as I tried putting the linkage in the truck, thankfully I had 2 different ones with me (much harder material) so swapped the squishy ones out and now I have working wipers.
One step forward, 2 steps back.... Trucks been running fine, parked it outside yesterday as I needed the garage to work on the 67 Mustang. Go to start the truck a little while ago and nothing, it's got power, battery reads 12.3v, but not cranking at all. My brain is saying things like "it's parked on a hill, nose down, maybe that's the problem" I just can't believe it started first turn of the key yesterday less than 24 hours ago.
Guessing another electrical issue, frustrated doesn't cut it. Of course it's also stuck outside again. Nice sunny day today, was looking forward to going for a drive.
Neutral safety switch comes to mind first. Try starting in neutral. Still nothing? 1, Turn the key to run position 2, using a screwdriver jump the positive going to the (relay solenoid) on the fender right by the battery with the smaller nutted wire. If it starts the hot wire going to the solenoid is either corroded or lacking power on crank.I've seen this many times and more than often it's just a bad connection where the starter wire goes to the solenoid and needs cleaning. Similar not exact video.
Update for this morning, put it in neutral, little tricky, the shifter indicator is currently not working, but it's on a hill, so I knew I found neutral when I took my foot off the brake and it rolled forward a little. Anyway, with it in neutral nothing happened.
From there, moved onto jumping the solenoid via the terminals circled in orange below and it cranks fine, turned key on and jumped the solenoid again and it ran, so I drove it into the garage. Took a test light, disconnected the green wire (red circle terminal), positive from the battery and test light clipped to that terminal it lights up. Assuming that is the correct wire for the neutral safety switch.
Assuming the green wire is the neutral safety, with it unplugged I then tried to see if I can get ground through the wire and am the test light is not coming on, I can't get the test light clip into the plug, so I used a small piece of copper wire into the plug and put the test light clamp on there. If I am correct in my thinking though, the fact I am not getting ground through that wire could that be enough to cause the truck not to start with the key?
Edit: Decided to lay down under the truck to look at the neutral safety switch, the middle wire basically fell off when I touched it then the plug fell off the switch itself, the black wire has bare wire showing.
Edit 2: Ran a ground wire from the solenoid terminal to the battery, engine started right up with the key. So, now to figure out a new harness for the neutral safety switch.
Last edited by Abcdefghii; 03-01-2024 at 08:47 AM.
The green wire in the lower right corner to my recall is the hot wire from the ignition when cranking. I would pull off the green wire from the solenoid and insert your test light into it. Turn your ignition key to crank and I believe it should get power to while in the crank position.
Next step
The neutral on the transmission is easily bypassed with a paper clip. Pull that off, insert paperclip or cotter pin to bypass and see if it cranks. Be careful that it's in park so it does take off down the road on you.
I think the green is the wire to the neutral switch, I laid down under the truck and the middle wire was not really attached, another wire was showing bare wire. But, the wire that was not attached matched the color of that wire on the solenoid. I ran a ground wire from the solenoid terminal to the battery, engine started right up with the key. So, now to figure out a new harness for the neutral safety switch.
That green wire does work off the safety switch by completing the loop. When the car is in gear it creates an open circuit via the neutral safety switch. I think you're on the right track.
Ordered a new switch harness, looks like all the typical parts stores have one, just not available locally. While I know I can leave it bypassed, I would feel better having the working switch.
02-18-2024, 05:06 PM
