Electrical System Upgrade: Remote Starter Relay Installation

[Michael Mayben]

The following synopsis is not unique to any IH vehicle. It's been incorporated on many vehicles in the last sixty years or so, including lift trucks, tractors/ag equipment, passenger cars, etc.

No one person/company developed this workaround, it has simply evolved over time. It's certainly not rocketscience...and is no different than adding any type of "relay" to any switch-controlled electrical load/circuit that was not properly designed/implemented at the point of vehicle manufacture.

The additional relay used for this is not a "Ford" item, but simply one type of relay that Ford used in some of their vehicle starting system scenarios. And many oem manufacturers used either the same basic part or something similar. There are literally thousands of similar-appearing parts available today in many different terminal configurations and ampacities.

For an example of just a few of the similar items available, check this link:

relays continuous duty 12 volt & 24 volt dc power relays,starter relays

For use in this case, the relay chosen does not need to be a high-current version, does not need to be a "continuous duty" rating item, does not need to be "heavy duty", etc. In fact, the least costly, oem replacement item will be more than suitable for what we're gonna do, those are rated for a nominal 100>150 amp continuous/350+ amp intermittent service which is more than sufficient for use in a starter circuit application.

Caution!!! This same relay is not rated for use in a relay pak used with many winches, lift gates, multiple battery charging systems, etc.

So to begin..."why are we even thinking of performing this upgrade"?? Simple...the oem ihc-produced electrical systems on the light duty vehicle side are simply marginal in design and execution. Most especially regarding the Scout II starting system but the pickall stuff is only slightly "better" in execution and all of the light duty vehicles can greatly benefit from this fix.

Some refer to this issue which we are addressing as the "hot start" problem. That is a total misnomer. That urban myth came from the fact that when many sv-powered (or I-4) Scout II vehicles were allowed to "heat soak" for say ten minutes in a parking spot and then an attempt at re-start was made, the engine would turn over very slowly, the starter solenoid would simply "click" as if the battery voltage were low, or nothing would happen starter-wise!

The workaround from IH for that condition was the addition of the heat shield between the exhaust headpipe and the starter solenoid/motor combo. For the most part, this same condition did not exist regarding the pickall platform, as there is much more air space around the exhaust headpipe and the starter system/inner fender. The tight engine bay configuration of the Scout platform (all versions) simply adds to this situation.

If the starter/solenoid combo is in average, servicable condition, and...all electrical connections are clean and tight, and... The battery voltage is correct, and...the wiring harness bulkhead connectors are in perfect condition with tight/clean plug-ins, and...the nss system/switch/relay is functional on a vehicle equipped with an automatic transmission, then this "hot start" issue usually never arises.

But...in the case of the average piece of IH junkiron we battle with every day, none of the above conditions are met unless we've already handled all that before making any electrical system upgrades. The addition of the remote starter relay will not fix any of the above issues.

A secondary reason for adding the remote starter relay is that it offers a "convenience" point for connecting a remote starter switch under the hood when working with the vehicle. And...the relay battery terminal is an excellent point from which to tap b+ for powering an additional "accessory" electrical load distribution panel.

 

[Michael Mayben]

A "starter solenoid" and a "starter relay" are not the same part!

A solenoid is an electro-mechanical component which imparts some type of mechanical action to a device in addition to serving as a super-duty electrical switch (high ampacity in our case). A relatively light duty (low ampacity) switch controls the on/off action of a solenoid.

A relay is simply a high ampacity switch which is controlled by a light duty control switch (such as a combo starter/ignition switch in our case).

In the case of the delco-supply starter motor/solenoid combo used in the IH light duty vehicle apps, the starter solenoid is mounted directly to the starter motor case. When current is supplied to the solenoid "s" terminal from the starter switch, full battery current is applied to the large motor terminal which puts the armature in motion. Also, the starter "clutch" (or drive) is shifted (the so-called solenoid "action") to engage the starter drive gear with the flywheel/flexplate ring gear to turn the engine over for starting.

When the ignition switch is released to the "run" position, the current is applied to only the "I" terminal which provides switched battery current to the ignition system to maintain engine run. Current is turned off to the starter motor, the solenoid is de-energized, and the internal solenoid spring causes the starter drive to retract (or "shift") away from the ring gear.

So...in the case of the IH light duty vehicles, they do not incorporate a "starter relay" in their oem configuration.

What we are going to do though is add a starter relay to the system and use it to control the oem starter solenoid/motor.

This pic is simply an example of one way to do this and is by no means the only way! I add the starter relay to a position on the bulkhead which allows the oem harness which is connected to the oem starter solenoid, to be relocated to the additional starter relay with no modification. However...if the wire terminations or the conductors on the oem harness are typical po-crapped, then that stuff must be repaired correctly before relocating the terminations.

 

[Michael Mayben]

And another variation of the starter relay mounting location, this one is used to feed the main electrical distribution panel on a Scout 80. The Scout 80 did not have any fuse panel or fused circuits oem!!! Only a circuit breaker (or a fuse depending upon year model) for the headlight circuit, and possibly a single fuse for the heater blower feed.

 

[Tiny Yokum]

Great work and pictures.
Thanks for the 411.

 

[Michael Mayben]

In both of the preceding pics, the relay used is a "grounded" type. That means the mounting bracket itself must be mounted to a metallic surface which is at ground potential, or has an auxiliary ground conductor connected to the mounting bracket.

The large copper studs are used for connecting the battery positive cable (here after referred to a b+) on one side, with an additional battery cable of the same gauge on the opposite terminal which will be connected to the large copper stud on the oem delco starter solenoid.

The other two small stud terminals on the relay "might" be marked "I" and "s", if it's an automotive application.

Typical part numbers by brand name for a relay of this type would be:

duralife: sw3-hd
standard: ss581x
niehoff: ff143a
eichlin: st81
borg warner: s63
wells: f496
gp sorensen: ss57

 

[Michael Mayben]

Here's a shot of yet another variation of the relay mounting position, this is Matt g.'s sii that was badly po-infected. The bulkhead connector/fusible link was burned down beyond hope and had the charging/ammeter circuit by-passed in a manner that prevented battery charging!

So Matt upgraded the starting system at the same time he did the dual battery install described in this thread:

http://www.forums.IHPartsAmerica.com/electrical-tech/2529-switchable-dual-batteries.html

Since then, Matt has installed a complete CPT/isspro instrument panel and decided to not use an ammeter (against my better judgement but then that is why we are friends!!), so the wiring has been changed up slightly yet again. But that does not affect the installation of the starter relay.

 

[Michael Mayben]

Once a mounting point for the relay has been selected, the ground point for the relay established, and the relay installed, it's time to swap the wire runs over.

before doing any electrical work on any vehicle, you must remove at least the battery ground cable from the battery negative terminal!!!

And now is the perfect time to revisit the entire ground system on the rig. I always use a bonded ground system which is a considerable improvement over the oem crap. That means that the battery negative terminal is grounded on the engine block. Then the engine block is grounded to the frame. Then the frame is grounded to the body (normally to both the front clip and the body/tub). And all ground cable runs must be at least of the same gauge as the positive battery cable that is going to feed the new relay and starter motor. For all my IH stuff, I use 2 gauge cable as it's a perfect size vs. Cost deal. The oem battery cabling on both sii and pickalls is 4 gauge.

Once the battery ground is disabled, then simply remove all the wire terminations on the oem starter solenoid and fish the oem harness out of the guide on the solenoid (not present on all versions) and bring it up to the mounting point where the auxiliary relay has been positioned.

Once the harness terminations are at hand, then carefully clean (that means bright metal!) the terminals and repair/replace if needed.

 

[Michael Mayben]

Now that the oem harness has been removed from the oem solenoid terminals, you will make your first wiring change.

A "jumper" must be added to the oem solenoid. I use a short piece of 10 gauge wire for the jumper with appropriate ring terminals crimped on for the two different stud sizes.

One end of this jumper will connect to the battery cable stud on the solenoid, the other end will connect to the "s" terminal on the oem solenoid. Simple! If ya don't do this, nothing will work!!!

 

[Michael Mayben]

And here is the jumper connected to the oem solenoid.

 

[efsonny]

Where is the "I" termnal in the remote solenoid wired to? I've never seen it wired or used before in my scouts. Is there a benefit? Thank you.

 

[Michael Mayben]

where is the "I" termnal in the remote solenoid wired to? I've never seen it wired or used before in my scouts. Is there a benefit? Thank you.

I got off on some other projects and haven't finished this little ditty!

Let me explain the wiring scenarios here and you'll understand there is not just "one" single way to incorporate this relay on any one particular vehicle (ihc or otherwise).

As efsonny mentioned..."sometimes" these relays are marked with witness marks if the relay was actually produced for use in a motor vehicle starting application. Most of these relays are not marked externally, since they are available in many different configurations for many different applications other than use in a vehicle starting system. But all versions appear similar to folks who don't deal with this every day.

The relays seen mounted here are in use on a Scout 80 that has had a complete custom wiring system laid in,...and on a '73 1110 pickup which has a wiring system virtually identical to a Travelall of the same vintage.

Both of the wiring systems on these vehicles are set up for a breaker point distributor/ignition system and are very similar in execution to a Scout II. But not exactly the same!

As the Scout II evolved from the beginning of production, so did the electrical systems all the way through the end of vehicle production! Changes for the automatic transmission spec from the bw 11 to the t-407 (tf 727). Changes from breaker point to electronic ignition variations, changes in emissions equipment inclusion (including 49 state and the California versions), changes in the climate control systems, etc. Can be easily gleaned by studying the dedicated wiring schematics by year model...same as for the fullsize stuff. One more time...these vehicles (by platform)...are not "all the same"!!

So...for our particular situation here, with the relay mounted so that it is hanging from the bracket (which is ground), the small terminal on the left is considered to be the "s" terminal and the small terminal on the right is the "I" terminal.

But for our purpose...what we are going to do is simply remove all cable terminations from the oem starter solenoid...and simply move the same set of terminations to the new relay!

Let's look at this more closely...

On the oem starter solenoid,...remove all terminations, including the battery positive cable lug and move those same terminations to the left hand, large lug on the new relay.

Then, you must run a new cable of appropriate gauge from the right hand relay terminal back down to the large terminal on the oem solenoid. The lug on the solenoid will then have two terminations mounted, one for the battery positive current feed, the other for the jumper to the "s" terminal on the solenoid which we made up a few posts ago.

Then, you will remove any terminations from the oem starter solenoid connected to the "s" terminal and move those to the new relay with the small terminal on the left which May also be marked "s". If your particular application has no termination connected to the "r" terminal on the oem solenoid (such as is the case with an oem electronic ignition system vehicle), then don't do anything with that termination point!

In the case of my own versions of this relay installation, I have modded the wiring somewhat in order to provide for some additional functionality which would not apply to most folks projects. This includes various "bypass" circuits for different format ignition system I use on both vehicles. Notice the two additional wire terminations that come down from the top, the red and yellow wires, we'll discuss that next.

 

[Michael Mayben]

Adding this remote relay to the starting system also creates an additional opportunity. That would be a convenience point for connecting a "remote starter switch" to use when the need arises to "bump" the engine over such as when trying to set the crank hub to tdc, doing a compression test, etc.

If you have one of the commonly available remote starter buttons, simply connect one pigtail to the "hot" side of the new relay, and the other pigtail connect to the left hand or "s" terminal. Then...when ya punch the button, the engine will crank over! But...depending upon exactly how your ignition system feed is set up (either with a bypass or not), even if the key switch is turned off, the engine will still start and run as long as the remote button is engaged. If you turn the key switch "on", then the engine will crank over, start, and then continue to run.

If...you turn the key switch on, and the engine starts from the remote switch/button, and then dies...you must turn off the key switch asap...otherwise ya run the risk of meltdown regarding the breaker points, any pertronix conversion, or an electronic ignition module/amplifier. Don't forget to turn the key switch off if the engine is not running!!!

On my rigs, I like to install a simple momentary contact push button under the hood in a convenient position to use a remote starter control. That is what ya see in this pic and in this case is mounted to my battery holdown this switch does not have to be a hd version (higher current rating), it only passes under five amps when operating and does not carry full starter current, that is what the relay we just added does!

 

[Michael Mayben]

Keep in mind...the addition of the remote starter relay does nothing to address the issue of the very poorly designed and executed oem charging system which is connected through the problematic bulkhead connector (male and female segments), fusible links (if present), crappy battery/starter/starter solenoid connection points, crappy ground(s), etc. This will not "fix" that stuff. Dealing with the bulkhead connector/charging system issue is a separate operation. But you May find that once you've jerked around on the wiring harnesses while doing this, the bulkhead connector (the one with the 10 gauge "pink" or "blue" wire runs) has gone tu too...so double check your work if this mod gives ya fits initially!

But it will provide a direct, clean current path to the starter and solenoid to reduce/eliminate voltage drop in the feed circuit. It will not "fix" a starter that goes away due to heatsoak, bad brushes, faulty/worn armature, or a solenoid with bad internal "switch" contacts.

It will provide a "convenience" point at the hot battery termination for the connection of an auxiliary load center.

 

[Matt G]

Then, you must run a new cable of appropriate gauge from the right hand relay terminal back down to the large terminal on the oem solenoid. The lug on the solenoid will then have two terminations mounted, one for the battery positive current feed, the other for the jumper to the "s" terminal on the solenoid which we made up a few posts ago.

For the visual learners among us:

I've since installed a remanned starter, but the wiring hookups are obviously the same.

since then, Matt has installed a complete CPT/isspro instrument panel and decided to not use an ammeter (against my better judgement but then that is why we are friends!!)

We are friends because you keep taking my sorry butt in every time it shows up on your doorstep, and teaching me how everything from carbs to remote starter relays work! And btw, the new gauges, charging system, and dual batteries all still work like a charm. Thanks for your help.

 

[Craig]

Nice write up! Link to dual battery install too.

This upgrade replaced my dash push button and allows me to use the key to start the engine. It allows the full voltage to get to the solenoid vs the 10-11 volts I was getting.

Mm you have been busy for sure, keep up the good work.
Looking forward to your other electrical write ups.

Here a pic of mine. I also added a terminal block which serves as hub for all the b+ connections.

Edit here a cool way to make cables too.

http://www.delcity.net/documents/movies/battery_terminals.mpg

I did not use there stuff, I just picked up some welding cable and the solder connectors at home depot. I took normal electrical solder 60/40 rosin core spooled out several feet and folded it back on its self until I had about foot long strip. I twisted that together to make one thick rod.
I put the connector in the vise, like the movie and inserted the cable and then used a propane torch to get it hot and feed in the solder. Worked like a champ.

 

[michaelp]

In my v8 800B, the battery is mounted on the drivers side. Can I connect the battery cable to the right side lug of the solenoid instead of left, and then go solenoid to starter on the left side lug?

Or can I mount the solenoid upside down?

Also, my two small terminals on the front of the remote solenoid are marked "s" and "I" - s is the left, I is the right. If I go b+ into the right side solenoid lug, can I still attached the stuff that was on the s terminal on the starter to the s side of the remote solenoid, or because I'm reversed do I have to attach to the I terminal? Thanks.

 

[michaelp]

I did this install today and answered my own questions. I just reversed the b+ stuff to the right side, starter cable to the left side, kept the s stuff on the s terminal on the remote solenoid, and it works like I charm. I started it up in 85 degree weather after driving for 1/2 hour and shutting down, and it started right back up.

 

[moosebrew]

I know this is an older tech thread but in case anyone else reading it was wondering like I was. You said you are using 2ga wire for this. I wanted to just confirm this is really 2ga and not 2/0ga? .25" diameter vs .36" diameter.

Thanks for the great tech write up. I'm gathering the needed parts to do this when the rain stops!

Mark

 

[sawmiller]

Hi Craig et.al. Just a note.
Solder is higher resistance than copper wire; therefore, crimp-apply force to press copper strands together- then solder.
The electrical connection is one of physical contact - the solder is just to keep it wiggle free. I made jumper cables which had a really nice solder connect and they never worked right.

 

[Craig]

Your right solder has more resistance over pure copper.

The best connection would be crimped for a strong mechanical connection, and then soldered to keep it clean and corrosion free. Then top it off with some adhesive heat shrink from the marine shop.

If your doing just crimp only, you can add some no-'ox-id grease to help with corrosion from road salts or start with tinned wire from gregs Marine wire.

if you want to go all out you could get some dlo cable, I have some at home just waiting for just that special place.