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Remote starter solenoid

K5-CJ5

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Ok so I swapped my old starter for a protorque mini starter. It works fantastic, amazing difference. I decided I wanted to keep the constant power off the starter and picked up a remote mount solenoid for the fender well. I took it out of the box and there was a warning label that said the diodes were not suppressed and not to use on a computer controlled engine. Its on an 84 so not an issue on this install but I was going to put one on my 87 k5 as well which is a TBI motor. Does this matter for the way we are utilizing them? If so does anyone have a part number for one that should be used.
 
Maybe it's because Ford uses "Permanent Magnetic Starters" in the newer vehicles? Some of the mini starters are also Permanent Magnetic Starters too, so you have to be a little careful when using a remote solenoid.

In my old race car I ran into an issue with my new mini starter.. I had always used a stock old GM starter and Ford solenoid on my previous setup which worked great, but needed a new "race/mini" starter for the 632 BBC that I was building. On the new high compression BBC I noticed that the starter would hang for a few seconds and make a horrible noise after the motor took off and I released the key. It was then that I discovered that my new mini starter is one of those permanent magnetic starters.

Here's how I understand the issue:
Permanent magnet starters can actually produce power if they are driven from an outside source (i.e. the starter will act like an alternator once the engine fires and starts spinning). The current produced in the starter for this second or so will flow from the starter's battery terminal to the starters ignition terminal and hold the solenoid in. This will cause the one to two second delay in the solenoid release and an irritating noise.

Maybe this is what the warning label is about???
 
I am right in the middle of a bunch of stuff, so I can't go into detail like I usually would.
Plus something does not sound right about that starter noise, but I'll look at that later.

The suppression they are talking about is for the coil in the solenoid.

Any time you have a magnetic field and a conductor moving in relation to each other, you produce electricity.
When you turn on the solenoid, the coil produces a magnetic field that expands outward to pull in the armature.
When you turn the solenoid off, that magnetic field collapses back down through the coils, plus the armature moves back due to the spring.

This produces a voltage of opposite polarity from the original which can be quite high.
A suppressed solenoid has a diode across the coil reversed according to the normal voltage.
When you turn on the coil, the diode is reverse biased and does not conduct. But, when the reverse voltage starts to develop the diode turns on and shorts it out.

You can look at the diagram of a solenoid and tell if it is suppressed. There will be a diode symbol across the coil.
There are several places that sell starters, winch motors and solenoids and they list which are suppressed.
Or you could add a diode to the one you have.
 
I fixed the noise etc. Now moving on to the remote solenoid. I did find one that was suppressed that I will use instead of the original one I picked up! Thanks for the info guys.
 
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