k guys just did a 383 carb swap to my 305 tbi 1991 rs i can start my car aout 3 times and watch my voltage slowly drop away my oil press gauge is maxxed out and my tach quit working as well took battery and alt to parts store and both tested good i checked all my grounds i have the three from the back harness hooked to my intake the negetive cable hooked to my front header bolt and from the terminal to the fender am i missing 1 or more grounds.the parts store also suggested me to hook the ground up that was connected to the water neck i didn't see 1 on my car or i may have cut it along with the smog pump wires? if i did where is that ground located ty again guys

 

Grounds - neg battery cable to block, groundstrap from rear pass head to firewall, and neg battery terminal to fender.

Starter - should have all fusible link plus the pos battery cable to the larer terminal on starter, and ONLY the purple wire on the smaller terminal.

Oil Pressure guage - you should have had a OPSU just above oil filter on the 305 - had 3 wires, two lager ones for fuel pump circuit (those are red and orange), and a black smaller wire (thats the guage wire). You'll need a oil pressure sender on the engine somewhere, and attach that smaller black wire to it.

 

my starter has two small wires hooked up to the same small terminal on my starter solenoid.also my OPSU has two light brown wires and a orange

 

If the positive battery cable is not connected to starter, you'll get nothing. The fusible links connect same terminal as the pos battery cable. The purple wire connects by itself on a smaller terminal.

 

http://www.austinthirdgen.org/mkport..._continued.gif

Above shows pos battery cable to starter, and purple wire on other terminal by itself - also shows your fusible links at power distribution block instead of at starter, either way doesn't matter. But the purple wire must be there, and all by itself in order for your ignition switch to start the car.

OK - one OPSU wire should be grey - runs to fuel pump, other should be black, runs to guage

Wiring diags here might help: http://www.austinthirdgen.org/index.php?pid=19

This site has great stuff - save it to favs: http://www.austinthirdgen.org/index.php?pid=2

 

ok this may be important to note the circle ends of my starter wire broke off (the single red wire from main harness) so i wired it into the main red wires (the ones with the 2 fuseable links in them) and there was two little wires that run to the same post on my solenoid and the red wire connector broke as well so i wired it into the purple key on wire think this may cause my voltage drop prob?

 

Maybe - not sure - not sure what all these wires are in your car. That's why I linked the wiring diags for you -you need to figure out what's what - sounds like someone hacked in a bunch of extra wires or something.

I do know that at the starter, there is one terminal for the purple wire, and it gets the purple wire ONLY. I also know there are NO ground wires to a starter - all starter wires are power wires.

One terminal on the starter get constant power from the battery - the pos batt cable. In some cars, there are also fusible links connected there, since the pos batt cable is there, these fusible links always have batt power (for things like lights, fuse block, etc) - that's how they get always on batt power to those circuits.

The other terminal takes the purple wire ONLY. This is the wire from the ignition that gets 12v+ from the fuse block only when the key is turned. This 'activates' the starter solenoid. A starter solenoid is a big relay. It has 4 basic connections like any relay:

1) constant high-amp batt power - this is the pos batt cable
2) Ground - the starter gets grounded on the block, which is grounded to batt via the neg batt cable
3) 12v+ 'activation' power - this is the purple wire
4) 12v+ OUT to the starter.

Purple wire sends 12v+ to the solenoid, which is already grounded (block), this completes a circuit that basically flips a switch inside the solenoid (activates solenoid) - this switch connects the batt pos cable to the actual starter itself making it turn. Just like a relay.

About all starters have 3 terminals on them:
1) smaller terminal - for the purple wire - it is physically smaller in size
2) larger terminal - for the batt pos cable - it is physically larger than #1
3) another larger terminal - connects solenoid to the starter itself - this one usually has a permanent metal tab between the solenoid and the starter rather than a wire, and is usually the closest terminal to the actual starter

All a car needs to start is 1) pos batt cable to the larger terminal and 2) purple wire to the smaller terminal, and 3) that metal tab connection between solenoid and starter. All the rest has nothing to do with starting, it's all just additional power wires for other parts of the car (like lights, fuse box, etc.) - easier to connect them to the same terminal on starter as the pos batt cable than to make a complicated battery pos cable with all these little wires running off of it.

Make sense?

 

yes ty for being so patient i'm gonna reconnect alt. and battery tonight and clip the red wire off the purple and see what happens hope it will fix the gauges and the battery draining situation i'll keep u posted

 

nope damn it same crap no charging ok lets do this tell me the bare ecential wireing of my 2 wire alt soi can totally rewire my starter and alt so there are no ways for this to continue btw my gauge fuse was blown put a new 1 in and all worked but my OPSU