Starter won't spin but solenoid clicks...

Personally I would put the relay inside the spare tire area high on the right side wall when facing the spare tire. I don’t like having relays in the weather.
I put my relay on the bracket for the A/C controls vacuum canister (which is mounted to the side wall in the spare tire area, just as Karl suggested above) . Somehow it feels less brutal to drill a hole in a bracket then in the car proper.

The gear reduction starter in my car uses a latching connector for the trigger wire, unlike the plain connector on the OEM starter. The gear reduction starter came with a pigtail to interface with the car harness, but when I put together the hard start relay harness I wanted to avoid extra connections. I found that TE housing part number 172128-1 is a perfect fit for my starter.

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This housing goes with TE contacts part numbers 170258-1 (12 - 14 AWG) and 170032-2 (14 - 20 AWG). I know there are a few different providers of gear reduction starters for our cars, and there may be different connectors used.



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My starter would click if I got a tooth on tooth engagement of the starter. I would put the car in gear, roll it a small amount and boom - car would start.

I installed a temporary hard start relay like this (it's not ideal as the relay is upside down, not great if it gets wet over time). Anyway, it works great! I'll eventually relocate it to the firewall or at least orient it differently.

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and this stopped the tooth-on-tooth problem? My starter seems similar: when it clicks is inconsistent and not easily tied to a pattern. Sometimes it fires right up, other times, ‘click’. And then the next ignition turn, starts up fine. Rebuilt starter from Snow’s Automotive 18 months ago.
 
and this stopped the tooth-on-tooth problem?

Indeed it did - the pull in current wasn't high enough to "turn" the Bendix gear in order to engage before I put in the relay. Now it does! :) Now, why does this happen? My car used to start just fine until about 10 years ago. My connectors are all good, and I changed the ignition switch once before. It seemed to help, but the problem came back.

Make sure your battery is nice and healthy as well.
 
Indeed it did - the pull in current wasn't high enough to "turn" the Bendix gear in order to engage before I put in the relay. Now it does! :) Now, why does this happen? My car used to start just fine until about 10 years ago. My connectors are all good, and I changed the ignition switch once before. It seemed to help, but the problem came back.

Make sure your battery is nice and healthy as well.
Where's the relay's fuse, if there is one?
 
Where's the relay's fuse, if there is one?
You put the fuse on the wire leading to the relay on the main power lead which will connect to the 30 on the relay.

Keep in mind that the original wiring did not put a fuse on the wire from the ignition switch to the starter. One reason for this is the wire is well protected and it really shouldn’t ever see more than the designed for amperage. In some ways a fuse adds a point of failure which is another thing to be checked for and as it is an undocumented feature, it becomes something the person trying to repair has to discover.
 
You put the fuse on the wire leading to the relay on the main power lead which will connect to the 30 on the relay.

Keep in mind that the original wiring did not put a fuse on the wire from the ignition switch to the starter. One reason for this is the wire is well protected and it really shouldn’t ever see more than the designed for amperage. In some ways a fuse adds a point of failure which is another thing to be checked for and as it is an undocumented feature, it becomes something the person trying to repair has to discover.
So would everyone likely add the fuse, or not…
 
As you have a 74 you already have a starter relay in the car with a push button in the engine bay to engage the starter. You should be able to use this existing system by bridging the seatbelt interlock system to take that part of the connections out of the loop.

This thread covers using what you have to make what you need:

This image is the critical one which changes the system to just be a starter relay:

View attachment 71062

You shouldn’t have to add anything to your car beyond connecting two existing wires directly to each other near the drivers seat belt buckle assembly.

However if the gnome who effed with your car did not understand this system and bypassed it entirely you have some work cut out for you.

For most X owners the following is what they would do to add a hard start relay:

This is what most X1/9s have: the battery which has two sets of wires attached to it, a negative which is bolted directly to the body and a positive heavy wire that goes directly to the starter (along with several smaller wires which bring power to all the other systems in your car). You have the ignition switch which receives power from the battery and when you turn the key to the start position now directs some of that power to a 10ga wire that runs from the switch, along the main tunnel and to the starter solenoid. When the wire has power to the solenoid it engages a winding in the solenoid which pushes the starter gear forward to engage the flywheel and second winding engages the 300 or so amps to the starter motor which will spin the gear engaged to the flywheel and hopefully your engine will start.
View attachment 71058

What you will be doing: Adding a relay between the ignition switch and the solenoid, getting power directly from the starter main lug to go to the 30 terminal of the relay with a new wire (with an inline fuse if you so desire), using the existing wire from the ignition switch to excite the relay, a wire to ground the relay and finally a new wire from the 87 terminal to the existing spade connection on the starter which used to have the wire from the ignition switch.
View attachment 71059
The fuse is optional, the existing circuit is not fused but if you want an additional safety step the new wire from the main lug of the starter to the relay can have a 30amp fuse.

What you will be making (roughly)

View attachment 71060

Personally I would put the relay inside the spare tire area high on the right side wall when facing the spare tire. I don’t like having relays in the weather.

The relay connections (rough because I need to go to work)
View attachment 71061

The wire from the ignition switch can be separated out of the wire loom in the spare tire compartment to got to the 86 terminal on the relay. The other three wires will be added.
Great info, thanks. If you put the relay in the tire area, where are you intercepting the original wires from, don’t they run directly from the tunnel to the engine bay area?
 
Great info, thanks. If you put the relay in the tire area, where are you intercepting the original wires from, don’t they run directly from the tunnel to the engine bay area?
The wiring loom passes thru the spare wheel well above the central tunnel, so it's easy to pull the one wire back into the wheel well you need (the starter solenoid trigger wire) and also feed to other two wires you add thru the same grommet in the firewall.

If you don't like the idea of splicing a fuse in the power feed line to the relay, you can buy relays with that fuse integral within the relay under a small cover, for a neater solution.

SteveC
 
The wiring loom passes thru the spare wheel well above the central tunnel, so it's easy to pull the one wire back into the wheel well you need (the starter solenoid trigger wire) and also feed to other two wires you add thru the same grommet in the firewall.

If you don't like the idea of splicing a fuse in the power feed line to the relay, you can buy relays with that fuse integral within the relay under a small cover, for a neater solution.

SteveC
Thanks. Seems like the fuse is optional in this application? But if I did, splicing is aok, as is your idea for a pre-wired :)
 
Great info, thanks. If you put the relay in the tire area, where are you intercepting the original wires from, don’t they run directly from the tunnel to the engine bay area?
In your particular case, you can use what is already in the car by following the image I showed on the previous page and shown below for those who have the starter interlock relay system.

FD49A0E0-ECB9-49C6-BB88-87CA365C8ADF.jpeg


There are two ways for those of us without the starter interlock to do this.

One is to pull the wire out of the loom at the bottom of the spare tire well, cut it near the bend at the floor and crimp in a 16ga wire to go to the relay 85 terminal. Then take the end of the heavy gauge wire you cut, put a new connector on the end of it and plug that into the 87 terminal of the relay. Run a new 10ga wire from the main lug of the starter to go to the 30 terminal on the relay.

The other is to just pull the red wire back out of the engine bay and connect that to the 85 terminal and run two new 10ga wires from the starter, one going to the main lug to bring power to teh 30 terminal and the other to carry power back to the terminal on the starter solenoid from the 87 terminal of the relay.
 
Thanks. Seems like the fuse is optional in this application? But if I did, splicing is aok, as is your idea for a pre-wired :)
A fuse is always optional for any piece of aftermarket electrical gear you install onto a car, it's also always a good idea and good practice to install one.

In your case not to protect the item being installed (a relay) but to protect the circuit from any accidental connection to earth of the power feed / discharge wire. I.e the fuse will blow rather than the wire / relay heating up and possibly catching fire... that's the safeguard you build in by fusing the feed wire.

There are sources in the engine bay that are 12 v constant (feed to the carby cooling fan) that are fuse protected at the fuse box so adding another fuse if you chose this circuit to feed the hard start relay would be redundant, but should you choose to take power from the main starter feed cable / alternator wiring then these circuits are not fused and it could be a good safety addition to add one to prevent your car catching fire.

SteveC
 
Thanks. Seems like the fuse is optional in this application? But if I did, splicing is aok, as is your idea for a pre-wired :)
FYI as I understand it the interlock relay for the starter your car already has is inside the passenger compartment. As it sits now it isn’t fused.
 
FYI as I understand it the interlock relay for the starter your car already has is inside the passenger compartment. As it sits now it isn’t fused.
And the interlock is not connected. But thanks for reminding me of that, I’d kinda forgot 😵‍💫
 
The downside of the stock 74 starter relay setup is that all the power gets drawn off the ignition switch. The good news is that there is only low current traveling through the starter contacts on the ignition switch. Since the current to the starter solenoid is quite intermittent and does not travel through ignition switch contacts in the process of closing, I'm not sure it is worth screwing around with changing where the system gets power. The main thing is that the ignition switch starter contacts are unlikely to get damaged by the coil current of the starter relay that is part of the seat belt interlock system..
 
The downside of the stock 74 starter relay setup is that all the power gets drawn off the ignition switch. The good news is that there is only low current traveling through the starter contacts on the ignition switch. Since the current to the starter solenoid is quite intermittent and does not travel through ignition switch contacts in the process of closing, I'm not sure it is worth screwing around with changing where the system gets power. The main thing is that the ignition switch starter contacts are unlikely to get damaged by the coil current of the starter relay that is part of the seat belt interlock system..
Hmm. The problem I'm having sounds exactly like Myron was saying. But he doesn't have a '74. I'd like it to stop, since it doesn't feel right, the clicking thing. Battery is new and healthy. Rebuilt starter has been in for 15 months maybe?
 
Hmm. The problem I'm having sounds exactly like Myron was saying. But he doesn't have a '74. I'd like it to stop, since it doesn't feel right, the clicking thing. Battery is new and healthy. Rebuilt starter has been in for 15 months maybe?
If the battery is good, and the starter solenoid is likely OK, then you have the classic "less than 12 volts being supplied" to the starter's magnetic solenoid to provide sufficient force to provide good contact at the starter solenoids high current switch.

You could test this by checking the voltage at the starters trigger wire. Disconnect it, connect a voltmeter to the spade terminal and to earth and turn the key to the start position, if it shows less than battery voltage then that's almost certainly the culprit.

That's what putting in the relay solves, it makes sure that the solenoids magnetic field is supplied with full battery voltage to ensure there is good engagement of the electrical side of the solenoid. It removes all the possible points where there may be high resistance / voltage drop in the starter solenoids magnetic fields trigger wiring path.... just the same as putting relays on the headlights or wiper circuits improves those by the same method.

SteveC
 
Hmm. The problem I'm having sounds exactly like Myron was saying. But he doesn't have a '74. I'd like it to stop, since it doesn't feel right, the clicking thing. Battery is new and healthy. Rebuilt starter has been in for 15 months maybe?

If the battery is good, and the starter solenoid is likely OK, then you have the classic "less than 12 volts being supplied" to the starter's magnetic solenoid to provide sufficient force to provide good contact at the starter solenoids high current switch.

You could test this by checking the voltage at the starters trigger wire. Disconnect it, connect a voltmeter to the spade terminal and to earth and turn the key to the start position, if it shows less than battery voltage then that's almost certainly the culprit.

That's what putting in the relay solves, it makes sure that the solenoids magnetic field is supplied with full battery voltage to ensure there is good engagement of the electrical side of the solenoid. It removes all the possible points where there may be high resistance / voltage drop in the starter solenoids magnetic fields trigger wiring path.... just the same as putting relays on the headlights or wiper circuits improves those by the same method.

SteveC
Where would you connect 'earth' to with the meters lead?
 
If the wiring is still stock, the current to drive the relay and to drive the solenoid comes from the ignition switch. I would check the voltage there before and during the starter being engaged along with the battery terminal voltages. If the voltage at the switch is OK, check that they are still good at the starter relay in the passenger footwell. If good there and the solenoid is still clicking, the problem may be with the wire from the relay to the solenoid. You might also check that the engine and battery are well grounded. If you see a significant voltage drop between the battery and the ignition switch, the problem may be in that connection. Also note that 74s had a huge problem with the ignition switch connectors. Mine went bad within weeks of getting the car. It went bad one day in 74 when I needed to travel so I cut off the connectors and soldered the wires figuring I'd find good replacement connectors later. Well, they are still soldered together and I've never had any electrical issues since. It does make removing the steering column a bit of a pain as it keeps it tethered close by. It is probably worth checking for voltage drop across the connector while drawing current. If the contacts aren't too burnt up, you can use DeoxIt D5 to clean them.
 
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