Wiring a 2 post ministarter for a C3 (1976)?
 

I am trying to get a 2 post mini starter wired correctly on my '76 vette with headers. I had one working, but it went bad, so I got an upgrade, think it's a 3 hp Hitachi.

1. It looks like this thing can be mounted to the block two different ways, solenoid up or solenoid down? Any advice on this?

2. When wiring it, I have 3 wires on the power side post and the ignition wire clipped in. I also bolted the ground and frame ground to a bolt on the starter case.

When I tried to start it with this new starter, it turned over and then wouldn't stop, even after I let up on the key. I had to disconnect the battery to get it to stop. I have no idea why this occured as the other mini starter did not do this and I had it wired the same way.

Any advice would be appreciated.

Thanks,
Dave W.

If it were me, I would mount it solenoid up to make it easier to get to the wires. The ministarters don't seem to suffer from heat soak like the original units did.

If it is not stopping, that can be caused by a bad solenoid (the contacts can create a hot spark that spot weld it in place), or it could be that it needs to be shimmed a little bit because it is binding on your flexplate/flywheel gear.

EDIT: Forgot to ask, what is the compression of your engine, and what is the timing at idle? I had the sticking problem with a stock unit and it was caused by the solenoid welding itself stuck because my 10:1 was too high for that crappy rebuild. I went through 2 of them before I took the solenoid apart to have a look. With a ministarter that normally wouldn't be an issue as they are gear reduction and don't hit as hard.

-dath

It's the stock 350 block (383 stroker). I think the compression is 9.8:1 duke to the iron sportsman heads I used. The weird thing is that with the solenoid up, the wires are all between the block and the solenoid. The wires barely clear the block.

Also, I forgot, I did NOT have the frame ground wire hooked up to the starter case on the first mini starter. This is the only difference in the way I hooked up the old mini starter and the new one.

I will try to add another shim, it very well could be hanging up, but if I shut the engine off should the starter keep spinning? This is what it did.

Certainly it shouldn't keep spinning in any case :D I wouldn't just shim it blindly, you should be able to just cram a paperclip between the gears when they are engaged.

I'm not positive about your wiring. . . Why did you run the frame ground to the starter? It shouldn't be a problem, but there should be no reason to do that either. . . It's been a while since I hooked mine up, but basically, you should have a small wire or two that go to the solenoid (can't think of what the second one was for) and then one large one that goes to the starter. That's it.

-dath

I believe the frame ground is hooked to the stock starter. I am pretty sure, but not positive that this was the case as the other small ground wire grounds several things in the '76 wiring, including the heater/AC blower motor.

Anyone have a basic wiring diagram for this?

Dave W.

The starter should have three lugs 1 big one for battery hot, S terminal is 12v from ign switch during crank, and I terminal is for ignition. Sounds like a bad solenoid or could have the S and the I terminals reverse. Hopes this helped. kurt

OK thanks for the input.

I am pretty sure that the starter only has 2 lugs. I am hooking the ground wires to the starter housing via a bolt.

The stock starter had 3, but these mini starters only have 2.

You need to wire differently when converting from a 3 terminal to a 2 terminal starter.

You should connect the large wire from the battery on the large terminal, the Start wire from the ignition/start switch on the small terminal, and the third wire needs to connect to the BOTTOM large terminal that feeds the starter windings WITH a diode in place to prevent backfeed or "run-on" of the starter. I have seen a "kit" somewhere that includes the Diode you need - but I can't remember where - perhaps Summit...

Summit sell this kit as do Powermaster..........but its expensive for what it is. Go to the Powermaster web page, they give you the rating on the diodes you need, then just go to radio shack and buy a pair (cost me $2) You need a little wire, a soldering gun and a round terminal and you can make the lead for no more than $3 (where as the summit lead will cost you nearly $30 with shipping and handling.)

Nick

The solenoid in nothing more than a heavy duty relay. The purpose is to control, turn on and turn off, a device that requires a lot of current by using a much smaller device (ignition switch). The solenoid will have a large power input terminal and a large power output terminal. The only other wire needed the wire from the switch to control it. Many older solenoids had an additional wire to the distributor system. When you turn the key it energizes the solenoid and it pass 12 volts at high current to the starter windings.

I'm not sure what the problem is; starter, ignition switch, wiring. If its not that big of a deal, drop the starter and check it on the bench or on the garage floor. All you need is a set of jumper cables and a short length of wire. Attach the jumper cables from you battery to the starter then use the short wire to put 12v on the small lug of the solenoid. The starter should spin and when the short wire is removed it should stop. It would be a good idea to place the starter in a vise as it will move when turned on and the jumper cables could come off and get together. If it works nomally, then you have other problems. If not, take it back.

I messed with it more today and at least the thing quit spinning after I let up on the key. The starter was dragging like heck, so I took it off and put the stock starter back on. The stock starter works much better. I don't know what else to do, so I am sticking with the stock starter I guess, at least until the solenoid goes from heat soak.

dw