Some electrical/wiring questions...

My starter harness finally arrived and when I went to fit it today, found that the original one had been modified.

On the new harness, at the starter motor end, is a plug with a black and purple wire in it. Is that for the theft interrupt relay? What ever it's for, on my original harness, the plug had been cut off and the purple wire terminated with tape. The black wire has had a small crimp put on the end and was over the small terminal on the starter motor. Does that sound like it's been done to take the theft relay out of the system? Oh, there's no earth wire anywhere near the starter like was pointed out to me in another thread??

What is the relay (I assume it's a relay) on the passenger side firewall near the blower motor? Coming out of the same loom as that relay is a tan wire, with a large ring crimp on it that reaches as far as the alternator if I pulled it across then engine. Any idea what it's for and where it goes?

Last one. Is the threaded hole in the block, below the dipstick for the oil temperature sensor? If so, is there only one wire going to it? I have a yellow wire dangling down in that area but my wiring diagram shows there should be orange and tan/white.

Sorry for the dullard questions but it's been ages since I removed these parts and some of the photo's I took at the time have since become corrupted.

saudivette said:

My starter harness finally arrived and when I went to fit it today, found that the original one had been modified.

On the new harness, at the starter motor end, is a plug with a black and purple wire in it. Is that for the theft interrupt relay? What ever it's for, on my original harness, the plug had been cut off and the purple wire terminated with tape. The black wire has had a small crimp put on the end and was over the small terminal on the starter motor. Does that sound like it's been done to take the theft relay out of the system? Oh, there's no earth wire anywhere near the starter like was pointed out to me in another thread??

Click to expand...

:bounce:You have a later shark, so it maybe a bit differant, as I know a later shark typically has a white molex plug up topside, where that starter harness plugs into....they frequently give troubles, turn brown and heat up with bad interconnects, mainly on the thick red wire coming from the alt feed to the battery post...there should be a 40? amp inline fuse OR a fuse link wire in there.....it connects the main harness to the battery and conversely feeds the battery it's charge off the alt......the purple wire as I remember, goes to the starter solenoid, small terminal closer to the engine, IF you have another small terminal, i'ts not used, it's for a points type dizzy in 68-74 years....so leave it blank, no wires....
any black wire leading to that area, if it was ME, I would pull it up topside and connect to the intake manifold, it's the way I rewired my car back when...that avoids ALL confusion with that 3/8 loop on it, that everyone want to put on the battery post....that ~10 ga black wire is the ground for the blower motor, blower motor high speed relay, on the a/c box you asked about, and the WSwiper motor.....without that grounded to the engine, nothing works well there, in fact the blower MAY run backwards slightly making you think it's all kosher....feeding back to another source....crazy but I BTDT......

saudivette said:

What is the relay (I assume it's a relay) on the passenger side firewall near the blower motor? Coming out of the same loom as that relay is a tan wire, with a large ring crimp on it that reaches as far as the alternator if I pulled it across then engine. Any idea what it's for and where it goes?

Click to expand...

as illudedd to above, that is the high speed blower relay, that oragne wire is supposed to have it's own fuse straight off the alt power block, horn relay on the driver's fender....the factory typically used a white fuse holder with a shitty 30 amp 1" long glass fuse in there, they typicall get hot and melt the fuse/solder inside the fuse, it LOOKS good but isnt'....I use another type 40 amp fuse/breaker in there, came from a boat application, it works....
I wire the hell out of my C4 blower for those power connections so I have nearly 1/2 volt drop across that motor directly compared to the system voltage.....max power to that C4 blower and I gots a freeking hurry caine inside there.....

saudivette said:

Last one. Is the threaded hole in the block, below the dipstick for the oil temperature sensor? If so, is there only one wire going to it? I have a yellow wire dangling down in that area but my wiring diagram shows there should be orange and tan/white.

Click to expand...

I think the size there is 3/8 NPT and is a normal PLUG, but they could put a sensor of some type in there, the L98 injected engine use the spot for a knock sensor on the driver's side...it's a drain plug hole for the water jacket, really and is normally plugged......got no clue as to your wiring there mate...

saudivette said:

Sorry for the dullard questions but it's been ages since I removed these parts and some of the photo's I took at the time have since become corrupted.

Click to expand...

eh, maybe I shed some light without adding tooooo much to the con fusion....

:bump:

The knock sensor (which was also installed on your 82!) threads into the passenger side drain plug, just above the oil pan rail in the center of the block.

Do you mean this hole here? right in the middle above the pan rail?

I just read my post back and have a slight amendement. The plug that I think is the theft deterrent is black and BLUE, not purple. Same as in this pic...

mrvette said:

:bounce:You have a later shark, so it maybe a bit differant, as I know a later shark typically has a white molex plug up topside, where that starter harness plugs into....they frequently give troubles, turn brown and heat up with bad interconnects, mainly on the thick red wire coming from the alt feed to the battery post...there should be a 40? amp inline fuse OR a fuse link wire in there.....it connects the main harness to the battery and conversely feeds the battery it's charge off the alt......the purple wire as I remember, goes to the starter solenoid, small terminal closer to the engine, IF you have another small terminal, i'ts not used, it's for a points type dizzy in 68-74 years....so leave it blank, no wires....
any black wire leading to that area, if it was ME, I would pull it up topside and connect to the intake manifold, it's the way I rewired my car back when...that avoids ALL confusion with that 3/8 loop on it, that everyone want to put on the battery post....that ~10 ga black wire is the ground for the blower motor, blower motor high speed relay, on the a/c box you asked about, and the WSwiper motor.....without that grounded to the engine, nothing works well there, in fact the blower MAY run backwards slightly making you think it's all kosher....feeding back to another source....crazy but I BTDT......

Click to expand...

Yes, there is a white plug that the starter harness plugs into and it's pretty horrible looking. The purple wire does go to the small terminal but of the black and blue wires that have had the plug removed, the blue one went nowhere and the end was wrapped up and the black one has been reterminated with the same size terminal as the purple wire. I can't remember pulling the damn thing off, but there's nowhere else for it to go and I'm can only assume that by running it that way, it will allow the system to work without the theft relay in there??? Up in the molex plug, there's a heavy guage red wire that runs into that black wire when the two plugs are connected.

mrvette said:

as illudedd to above, that is the high speed blower relay, that oragne wire is supposed to have it's own fuse straight off the alt power block, horn relay on the driver's fender....the factory typically used a white fuse holder with a shitty 30 amp 1" long glass fuse in there, they typicall get hot and melt the fuse/solder inside the fuse, it LOOKS good but isnt'....I use another type 40 amp fuse/breaker in there, came from a boat application, it works....
I wire the hell out of my C4 blower for those power connections so I have nearly 1/2 volt drop across that motor directly compared to the system voltage.....max power to that C4 blower and I gots a freeking hurry caine inside there.....

Click to expand...

Ok, but where's it connected to? I know it wasn't connected to the back of the alt, so does it go to the starter as well?

mrvette said:

I think the size there is 3/8 NPT and is a normal PLUG, but they could put a sensor of some type in there, the L98 injected engine use the spot for a knock sensor on the driver's side...it's a drain plug hole for the water jacket, really and is normally plugged......got no clue as to your wiring there mate...

Click to expand...

I don't actually remember pulling anything out of this hole. I stuck a piece of wire in it earlier and it feels blind but maybe there's a smaller hole in the centre. It was too dark to see anything and I couldn't really get my head up there anyway. I'll have a gander with a torch and mirror tomorrow - it just threw me with a convenient wire hanging there and a threaded hole?!?!

mrvette said:

eh, maybe I shed some light without adding tooooo much to the con fusion....

:bump:

Click to expand...

No mate, it's cool - very helpful :thumbs:

Twin_Turbo said:

The knock sensor (which was also installed on your 82!) threads into the passenger side drain plug, just above the oil pan rail in the center of the block.

Do you mean this hole here? right in the middle above the pan rail?

Click to expand...

No TT, the knock sensor's still there but not connected to anything. My dipstick's on the driver's side and there's a threaded hole just underneath where the dipstick fits to the engine...

Wayne, sorry I dunno what to say, about your reply.....guess I have to ask for more specific question, as my direct knowledge of your car is slight at best, only been some 7 years since working on one...sorry....

your harness there dose look familiar, but being an old ET, I would never BUY a harness, and indeed did my own so long ago but yet I read it instantly....

as for the hole in the block TT shows, yes, that a coolent drain plug in fact, was intended that way when the blocks were drawn up for production some 50 years ago....but they are used for knock sensors...so yours is on the pass side...same thing different day....

:gurney::clobbered:

The plug with the black and blue wires is for the temp switch for the Aux Fan. The red wires with the big ring terminal go to the battery connection, the Purple one is the S wire for the starter solenoid.
If there is a black one its a ground.

In reality there are two differant feeds for the blower motor, strangely enough, that 30 amp typically silver color relay on top of the a/c housing type area is the high speed relay....it is fed by that heavy ORANGE wire and when activated that relay actually feeds direct alt voltage to the blower, directly off the horn relay/alt output stud....with a 30 amp fuse in it....

the lower speeds are selected by the resistor pack in the top of the blower housing...yell/blu/grn wires to it...maybe another one too....that goes to the speed switch inside, and it in turn gets a feed from a fuse inside in the main fuse block.....crazy but true...so you allways have a blower of some sort....typically.....

:ghost::flash:

Lord knows what's been modified and why. I'll have to wait until I've got a battery and see what power's going where. Like I said, the blue and the black wires with the plug on the end had had the plug cut off and the black wire re-terminated in a small ring terminal. When I went to plug the new starter harness in, I noticed that the previous re-terminated black wire had connected (within the plug joint) to a large gauge red wire.

Doesn't make sense to me what was achieved by doing that - I can only assume it was to provide power TO the aux fan plug. With the plug cut off and the wire re-terminated why would it then go to the starter solenoid?

As for the other wires, I've spent ages going through pics I've taken of other items and managed to follow the wires through many of them - the pics I specifically took have since become corrupted?!?! Anyway, the long tan wire that's coming out of the same loom as the blower relay, was held down on one of the studs that hold the driver's side hood latch mechanism???

The yellow wire actually goes to the distributor :bonkers: the wiring diagram shows pink and white and I have yellow and orange. The yellow wire I was trying to sus is twice as long as it needs to be to reach the dizzy and has been bastardized and chopped and bubba spliced together...

saudivette said:

Lord knows what's been modified and why. I'll have to wait until I've got a battery and see what power's going where. Like I said, the blue and the black wires with the plug on the end had had the plug cut off and the black wire re-terminated in a small ring terminal. When I went to plug the new starter harness in, I noticed that the previous re-terminated black wire had connected (within the plug joint) to a large gauge red wire.

Doesn't make sense to me what was achieved by doing that - I can only assume it was to provide power TO the aux fan plug. With the plug cut off and the wire re-terminated why would it then go to the starter solenoid?

As for the other wires, I've spent ages going through pics I've taken of other items and managed to follow the wires through many of them - the pics I specifically took have since become corrupted?!?! Anyway, the long tan wire that's coming out of the same loom as the blower relay, was held down on one of the studs that hold the driver's side hood latch mechanism???

The yellow wire actually goes to the distributor :bonkers: the wiring diagram shows pink and white and I have yellow and orange. The yellow wire I was trying to sus is twice as long as it needs to be to reach the dizzy and has been bastardized and chopped and bubba spliced together...

Click to expand...

OK, the YELLOW wires are basically a lower power circuit which is switched OFF when the engine is cranking, but ON when the key is relaxed and the engine running.....same as would be for radio or any other accessory....

assuming wired correctly from the fuse block, which in turn goes to the ignition switch on top of the steering column, burried where hell can't find it....so the FACTORY yellow wires you seeing usually fed the WSWiper motor, and maybe some other small shit....the PINK wire feeds the HEI...it's a heavy looking 10 ga or so wire coming from the ingnition switch through the bulkhead connector....That is obviously hot in both start and run positions of the ign sw.......

I hope you know/understand a single pole double throw switch....hot to the center contact and depending on how you toss it, one side OR the other is your hot contact....so the ignition sw has one of them in it along with many others....takes main power red wire input, allways hot, and when the switch is in the run position, connects to HEI PINK, also done in start.....that's the on off function for the pink wire only....the SPDT switch is the yellow accessory feed, and so i'ts hot with ign sw on, but that voltage is applied to the starter solenoid small S terminal and removed from the yellow wire when CRANKING ONLY......

hope this didn't muck up the waters too much for you....


GENE