Ok. I'm having an issue with my starter wiring. I have a summit high torque mini starter. I mounted an external solenoid on the fire wall to help with hot starts... it still turns over slow however.... anyways. I have the positive cable running from the battery to one side of the solenoid..and then from the opposite side to the starter... the s terminal is hooked to the ignition and the small and big post on the starter have a jumper together.... . I was just replacing the starter on my 77 vette. Same parts but the positive cable is hooked directly to the starter on the vette.. the s terminal goes to the ignition and the small post on the starter is hooked to One of the big posts on the solenoid mounted on the firewall... it's always started fine. Is this wrong? A better way to wire it than the way I did the bird???
A couple of questions to verify what you have set up. Your external solenoid, is it a starter solenoid such as the ones Ford has? It has to be a high amp solenoid. I'll post a photo of what I mean. When you say your S terminal is connected to the Ignition do you mean the ignition switch or the coil?
The GM starter has three terminals. The large Batt terminal connects to the battery + via the large battery cable.The S terminal connects to the ignition switch via the # 10-12 purple wire. The R terminal connects to the coil + via the brown/black wire, either directly to the + stud of the coil or it junctions the resistance wire from the ignition switch then goes to the coil. The large Batt terminal may have other wires coming from it as well to run accessories.
When you turn the ignition switch to start the purple wire closes the starter's solenoid which engages and powers the starter and also provides 12 volts to the ignition. When you release the key the starter powers off and the ignition is powered 6-9 volts via the pink/white/blue resistance wire from the ignition switch. That is with a points ignition, HEI has 12 volts start and run.
Remote solenoids are used to reduce problems of hot start and also eliminate wires running down to the starter around the hot manifolds. With a remote solenoid you should only have the + cable from the solenoid to the starter, no other wires connected to the starter at all. Any accessories can be connected to the Batt side of the solenoid.
Do this: Mount the solenoid as close to the battery as convenient.If that's the firewall, fine, if it's the fender, fine also; Make sure the solenoid has a good ground, doesn't hurt to run a ground wire from the mounting screw/bolt to a good ground on the frame, block or the battery NEG post; Connect a cable from the battery POS post to one of the large terminals of the solenoid; Connect a cable from the other large terminal of the solenoid to the BATT terminal of the starter; Connect a jumper plate or #10-12 wire from the BATT terminal of the starter to the S terminal; Connect the purple wire that was attached to the starter S terminal to the S terminal of the solenoid, that is the wire that goes to the start terminal of the ignition switch. If the purple wire is too short extend it with a piece of similar coloured wire of equal thickness.If your remote solenoid does not have the terminals marked S and R connect it to a small terminal; Connect the wire attached to the R terminal of the starter to the other small terminal on the solenoid, that is the wire that goes to the coil; Transfer all other wires that were attached to the BATT terminal of the starter to the large terminal of the solenoid that is connected to the battery.
Now when you turn the key to start the solenoid closes and the cable to the Batt terminal of the starter is hlive, the jumper from Batt to S terminal powers the starter's solenoid and the engine cranks. 12 volts is supplied to the ignition from the second small terminal of the solenoid. When you release the key all terminals of the solenoid are dead except the side connected directly to the battery.
Engine should crank well with the mini starter if you set it all up correctly and have a good battery. Try checking the battery ground cable where it is attached to the block, must be a tight and clean connection.
The solenoid on the Vette is not set up correctly. It is using the solenoid to power the S terminal of the starter. No advantage to that unless the original S wire from the switch has some resistance somewhere and not supplying 12 volts to the starter's solenoid. Better off removing it and repairing the original wiring or setting it up as the Firebird's remote solenoid.
that looks like the same solenoid I have... thank you for the detailed explanation... I am going to revisit both cars tomorrow.. the vette was done before I got it and its never had starting issues.. ive had it for years... the firebird however I believe is set up exactly like you explained and still turns over slow.. I will double check....
Well you said you have the S terminal connected to the ignition and you never mentioned the R terminal. Perhaps your starter doesn't have one. If the wire you have from the S terminal goes to the coil that would give you the 12 volts for starting. I would run my coil power wire from the relay rather than from the starter just to keep it out of the heat. Maybe the solenoid has an internal resistance and is not giving full battery voltage to the starter. You can check the solenoid by disconnecting both large terminals and use an ammeter to see if there is a resistance from one large stud to the other when the solenoid is energized. You can also leave it connected and put a voltmeter on both large studs when starting to test for voltage drop across the solenoid contacts, Do not let the studs rotate when you tighten the nuts, if the studs rotate the solenoid will be ruined and you will have to buy another. I have a Powermaster geared starter on mine, it's 464 cubic inches and 10.5:1 compression ratio, the starter spins it over quite well hot or cold. Yours should be the same unless you have a very high cylinder pressure. Good luck.
Pretty obvious but you did check condition of the battery, right? I dealt with slow cranking and no hot starts for a couple of months ( only a couple of trips) before I bought a battery checker and figured out the Optima had given up.
Note that external solonoids don't help hot slow cranking. You need a 1000 CA battery and heavy cables like 1 gauge
I have 1000 CA battery.... all new parts... still turning over slow.. not just when hot I notice too... I may replace the battery just to be sure.... ill put it in my truck as the 2nd battery and get the bird a new one... I took it out today and boy its got some power!! yeah!! been a long project but so worth it!!!
as a side note.. can anyone see a reason their would be a ground wire on the I terminal?? of a remote solenoid?? the vettes up and running but it had a ground wire from the body to the I terminal I didn't hook back up.... seemed odd since the solenoid was grounded to the body.
still chasing this issue.... the battery tested 12.2 with the car off and nothing on.... my truck was 12.7.. vette was 12.5 with a brand new battery in it..... I think I need to go thru the rest of the wiring on this.... there are no other wires coming into the system.... only the positive cable is connected to the starter.. only the positive battery cable is running in and out of the solenoid...along with 1 wire to the ignition on the small terminal.. shouldn't the alt. wire be connected to the battery or the solenoid?????
ok... update...im seriously confused... lol.... heres my question.. where does the alternator wire come in to the charging system?? I traced the 3 alt wires to the volt regulator..then to the fusebox area.... but as far as I can see there is no wire entering the positive battery wiring... shouldn't there be a wire from the alt to the starter or battery or starter solenoid?? also, the flat plug on the alt has 2 wires... can those wires be backwards? in other words.. I replaced the plug and the new plug had different color wires..
I think that was it,, that connection was pretty bad.... I also ordered a kit to wire another wire from the alt. to the battery side of the solenoid... it comes with a inline fuse... I may not need it. the car was starting pretty good today after a few short rides.. although its only 60 degrees here.. lol..