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Complete Me (Wiring Diagram)

62K views 41 replies 11 participants last post by  47Ford - 1.5Ton 
#1 ·
Alright guys... lets utilize some MS Paint, and help a 'special' guy out. (AKA ME!) Anywhoo.... looking for someone to connect the dots on this for me.





SEARCH TAGS: 4BT wiring, starter, alternator, solenoid, fuel

(right click on expanded image... save as.... edit in ms paint, reload back onto 4BT swaps)
 

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#2 ·
haha... awesome... You just saved me from having to do that!

I haven't wired mine yet, but from what I've read, the white wire from the fuel solenoid is the 'pull' wire and I'm assuming that is on the same circuit as your starter solenoid. Then the red wire is the 'hold' wire... I assume that needs to be hot in the run position of the ignition (I plan on using my old coil lead). Then the black is ground.

Don't make fun... help us!
 
#9 ·
More Information

By your pictures I assume your engine has a 1 wire fuel soleniod so the pull in and hold in curcuits are no good for you. More on that later. I see you have a key switch, a starter with the solenoid seperated from it? and a battery and of course an alternator. Also the fuel solenoid. Am I correct on this?



The type of soleniod that has three wires is the pull in hold in type these are a large external solenoid that mounts near the fuel pump and actuate the fuel control on the pump, I am not sure but I have only seen these on inline pumps, all the rotary pumps I have seen use the cartrage style one wire soleniod that screws into the pump itself. White is the pull in voltage or the big load that should be wired threw an intermitent solenoid off the S term of the starter, or the key switch, the terminal that supplys the cranking voltage to the starter solenoid. The red wire is the hold in which is a lower load and can be wired from the Ignition side of the key switch, wiring this from Accessory side would power the hold in solenoid while the key was in acces, radio on etc. this would cause premature failure.




let me know about the components your wiring together as I listed them above and I will try to help.
 
#10 ·
By your pictures I assume your engine has a 1 wire fuel soleniod so the pull in and hold in curcuits are no good for you. More on that later. I see you have a key switch, a starter with the solenoid seperated from it? and a battery and of course an alternator. Also the fuel solenoid. Am I correct on this?



The type of soleniod that has three wires is the pull in hold in type these are a large external solenoid that mounts near the fuel pump and actuate the fuel control on the pump, I am not sure but I have only seen these on inline pumps, all the rotary pumps I have seen use the cartrage style one wire soleniod that screws into the pump itself. White is the pull in voltage or the big load that should be wired threw an intermitent solenoid off the S term of the starter, or the key switch, the terminal that supplys the cranking voltage to the starter solenoid. The red wire is the hold in which is a lower load and can be wired from the Ignition side of the key switch, wiring this from Accessory side would power the hold in solenoid while the key was in acces, radio on etc. this would cause premature failure.




let me know about the components your wiring together as I listed them above and I will try to help.
The normal cummins starter with a main wire and then a smaller terminal on it... I have a 'starter solenoid' with 4 posts on it... my fuel solenoid is what I beleive to be just a 1 wire (VE PUMP) and I want to say a 3 post key-start ignition switch.

Basically I have all the piece parts that I kept from the P30 step van... if picture are needed of the starter solenoid, alternator, fuel pump, and the starter itself... I can do.
 
#12 ·
It worked.... but its just a part number page of the 4bt with electrical components.
 
#13 ·
TM Diagram

Hope this helps a little, it is the typical wireing for a Trackmobile with the 4BT and an inline style Pump so it has the 3 wire fuel solenoid, this shows how we wire the starter very well, we use an intermitent solenoid to control S term Voltage as to not overload the keyswitch with the high amp load of the starter solenoid. I know its confusing as he77 but hope it helps.
 

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#14 ·
You can also see how to wire a three wire fuel soleniod from the diagram I posted, on your set up with the one wire you will be just using the ignition post of the key switch for the fuel soleniod.
 
#17 ·
Help me out here guys..... A. what is what on the Solenoid....... and then what is what on the starter. (Yes guys this is my current motor and chassis.... now you know how much work I did to get it looking like it is now.)

NOTE: This is always why you have a camera handy during disassembly





 
#18 ·
I also run a one-wire alternator. My starter solenoid, is like, only 12" from the alternator, so I wired the output on the alternator into the first side 5/16" stud (hot all the time)

YOU CAN GO TO THE MAIN STARTER LUG OR TO THE POS + ON THE BATTERY. IT DOESN'T MATTER as long as the output of the alternator goes to a "hot all the time" POSITIVE circuit.

 
#19 ·
I think the way you have that drawn up though it would always bypass the solenoid..... follow red loop to right of solenoid between altenator and starter.
 
#21 ·
So then the components needed to start the engine are: ignition switch (key), starter, battery, fuel solenoid and then the alt for charging... correct? Mine didn't have a starter solenoid separate from what was on the starter so I didn't plan on adding one.
 

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#25 · (Edited)
Nuetral Saftey.

We are all forgeting about the saftey curcuits here, the start curcuit needs to be interupted with some type of clutch switch on the standards and of course the nuetral saftey on the autos. This is why the extra soleniod is used on the s curcuit in the Trackmobiles because as the start voltage crosses all the switches we use it looses Voltage and the ability to pull in the soleniod the harder the soleniod is pulled in the better the conection is made for the cranking voltage. The higher the cranking voltage, the lower the amps, the lower the amps the longer everything lives!
 
#26 ·
.... the longer everything lives!
Haha~ good point.

Just wanted to say I got it running tonight. I had some issues with a corroded starter lead left over from the bread truck... replaced it, upped the rest of the temporary wires to 12ga, fresh charge on the batt and away she went. Started so smoothly, gave me a puff of black smoke (and a hard on).. Got so excited I ended up finishing the exhaust and putting the tub back on it tonight (all bodywork is complete already so just a matter of putting it back on). I took video and just have to post it on youtube. Pardon my shi# eating grin in the video!

This weekend I plan on finishing fab work on the grill for the innercooler, radiator and fans and doing all the plumbing. Then I'll hook up the important gauges and drive the sh*t out of it!
 
#31 ·
I dont think that the solenoid pull in on the starter should be a problem for the switch. Cars ran for years with the switch wired directly to the solenoid. However, I do agree an isolation relay is needed for the IP solenoid pull in. You can piggy back the solenoid from the solenoid start terminal as it only needs a short pump of power to pull in. I did mine like this and has worked perfectly every day for over a year(my conversion is my daily driver). I used a 20A relay from RadioShack....a nice Idec would have been better, but the little plastic/epoxy sealed ones are nice to mount and cheap. I can replace it in 2 minutes if it fails some day.

I also agree on the safety circuits....good idea and use isolation relays. I used to do control circuit design for a living and could do a nice diagram if there is a need in the tech section. I dont have alot of spare time right now, but could probably get it in a week or two if you guys think it would be helpful in the future.
 
#34 ·
I dont think that the solenoid pull in on the starter should be a problem for the switch. Cars ran for years with the switch wired directly to the solenoid.
Yes sir, I remember the good ole days too! My first car actually had a factory installed push button starter switch mounted in the dash - a 1950 Chevy Deluxe. That's when they built cars heftier than some of today's half ton trucks. We just have to keep in mind what we have to work with today. Remember the factory recall on the Fords not long ago that had the ignition switches fail and ignite while the car was parked overnight in the garage? That is what we have to deal with today. Either way will work. So it can just be a matter of preference. ;)
 
#32 ·
Does the IP need just a momentary shot of current and then it no longer needs power once fuel is flowing or does it need a constant supply of power to remain open? (AKA: instantaneous power or continuous?)
 
#37 ·
A relay to isolate the switch is definately not a bad thing....I dont mean to say that. It just adds to the complexity and "components that can fail list" if it is not needed. I actually spoke prematurely not knowing if the first gen solenoids are the same as the second gen's. Mine is a P7100 with one pull-in wire and one hold wire. The pull in gets the in-rush current and only a small amount of amperage is required after that. Mine is hard wired or I would check it and let you know what the continuous current is....again, I have run it for over a year every day with a 21 year old ignition switch wired directly to the hold switch. Of course it ran it's first 20 years holding in chevy diesel IP solenoid so it could possibly have a factory iso relay I am unaware of, but I dont think it does.
 
#39 ·
This just in!

I replaced a starter ring gear last week in a piece of equipment at work, the new ring gear and starter sounded as though the ring gear was 2" out of round. Trouble shooting showed the s term voltage at 10.5V when this voltage was brought to 12V via an isolation relay the starter sounded like a complete different unit. The engine turned over like the injectors where removed. I agree wired direct everything will work, on equipment however there are extremes, the unit might be started 50 times in one shift, how long would it be before a normal daily driver gets 50 starts? See my point? Take this info as you may but, I know how I am going to wire my starter.

By the way the 10.5V s term voltage is above the manufactures 9.6V spec. for s term voltage. Makes me wonder what the manufacturer was thinkin!

It will just live longer!
 
#40 ·
I agree wired direct everything will work, on equipment however there are extremes, the unit might be started 50 times in one shift, how long would it be before a normal daily driver gets 50 starts?
On my daily driver, less than a week. I'm in and out of my truck all day and probably start it 10-20 times a day, depending on how busy work is.. Probably the exception to the rule, but I figured I'd point out that not everyone's vehicle usage is the same.
 
#42 ·
Well.... round 1 complete

We are completely wired up. EUREKA... the starter works and spins on key-demand. (I dont have the starter spacer yet...but Scott (CrewCab59) hooked me up.)

Pending delivery of starter spacer and radiator... were a GO this weekend.
Power steering pump is now yblocked......(aka. pressure out tube comes into a y-block brass fitting.... and then feeds the 2 lower pressure inlets)

Fuel Pump solenoid...... clicking
Inline solenoid...... clicking
Starter Solenoid.... clicking
Starter.... spinning and spinning fast. (did 2 momentary starts... didn't want to outspin the starter since it didnt have any resistance loading... (the flywheel))
 
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