Runaway Engine Start Condition

[Melon00]

Originally Posted by THenne1713

Twinboat wrote: <<The OP posted that he found the bad solenoid, one post before yours.
Should at least read the OPs posts .>>
REALLY NOT trying to start a cat fight, but you partly missed my point of MY story, re: CUBE RELAY = NOT SOLENOID. My D21 starter solenoid is starter mounted, and was a new starter & solenoid when I had HIS same symptoms of starter running, but (similar to a Ford F53 cube relay in fuse box CONTROLLED BY auto trans Neutral switch), D21 has an under-hood wheel well mounted cube relay (CLUTCH PEDAL SAFETY SWITCH controlled by clutch, manual trans on mine). Made no sense to me electrically, but was only part left besides wiring, and replacement cured the uncontrolled cranking, and the SLOW crank. I had last replaced that relay in 1997 when I had a NO CRANK situation .. and no, I do not understand, (I do know it should theoretically never have given the starter RUN symptom when key removed, but it did).. somehow

I learned a lot about how these systems work, so I wanted to pass along what I learned which may help you understand the failure.

My understanding is that the transmission prevents starting the engine while not in neutral or park to prevent catastrophic damage. There are several ways to engineer this into the starting circuit, but all manufacturers are addressing this same problem.

Those cube relays are electro-mechanical, meaning not 100% electrical, so you have internal moving parts that can get stuck just like anything mechanical. This is why the industry is moving towards solid state relays, which are 100% electrical, however solid state relays (SSR) have certain limitations, so their electro-mechanical (EM) counterparts won't be going away any time soon. Most EM relay failures are catastrophic in that they just won't operate (your first problem in 1997). Relays also have a dangerous failure state where it is stuck on (my current issue). However, because EM relays have a mechanical function, it opens the door for intermittent failures where the mechanical components need a little "lube" to move freely, so to speak. Obviously, you can't lube the components, so your stuck replacing (your second problem).

Hope that helps.

[FormerBoater]

Based upon the pictures posted by the OP I am surprised that anything is functioning properly.


I have seen quite a few examples of absolutely poor workmanship when it comes to crimping ring tongues and butt splices, but the terminations and splices on his rig indicate that the wrong application tooling (crimper) was used and who ever did the installation had no idea what he/she was doing.


Cracked insulation, crimps made in the wrong location etc. As the OP is obviously quite handy, I strongly recommend re-terminating all of the connections and butt splices with mil-spec (vibration resistant with copper insulation support sleeve (Amp PIDG or equivalent) and the investment of a crimping tool that will crimp the wire barrel and the insulation support sleeve in a single use of the crimping tool.


JMHO but after 21 years in the electrical connector business I had to chime in here!

[153stars]

Got ya sometimes you see certain elect bay with other solenoids and think DP wise. You could use as original as a pilot relay, but if the other lasted that long you should be okay for a while. Once you remote it won't have to dig to find again and know exactly what do ,it's bulletproof from now on. Carrying a spare will further prevent its failure.

Originally Posted by Melon00

Thanks for your recommendation. That appears to be a good product.

I gave it more thought and since the circuit is wired into other things, like the transmission position switch, I don't want to install a relay with a bigger coil to draw more current than designed, thereby taxing the other devices in the circuit. I'm hoping relocating it will reduce the likelihood of a dangerous failure in the future. I'm also going to see if I can cut into the starter circuit using the chassis battery disconnect switch so I can quickly cut the controls circuit out with that switch, should it reoccur.

[Xmcdog]

Originally Posted by FormerBoater

Based upon the pictures posted by the OP I am surprised that anything is functioning properly.


I have seen quite a few examples of absolutely poor workmanship when it comes to crimping ring tongues and butt splices, but the terminations and splices on his rig indicate that the wrong application tooling (crimper) was used and who ever did the installation had no idea what he/she was doing.


Cracked insulation, crimps made in the wrong location etc. As the OP is obviously quite handy, I strongly recommend re-terminating all of the connections and butt splices with mil-spec (vibration resistant with copper insulation support sleeve (Amp PIDG or equivalent) and the investment of a crimping tool that will crimp the wire barrel and the insulation support sleeve in a single use of the crimping tool.


JMHO but after 21 years in the electrical connector business I had to chime in here!

The crimper I hate to see is the so called punch through type. Cheap and nasty. In many cases there is only a few strands that are firmly in contact with the terminal. Get a good ratchet type.

Butt connectors are for temporary work only, to get you home.

[Melon00]

Attached are the photos I promised, in case someone else needs it for reference. It was the original location of the starter relay and a closeup photo of the model number of the relay itself.

[twinboat]

That's different then any others I've seen. Most are solenoids like what was displayed a few posts back, except they have 2 small terminals.
A bit more robust and mounted on the chassis rail.

[THenne1713]

Twinboat,
is (similar to) the one for the Nissan that I described, and believe the Ford F53 has similar mounted in an under-hood FUSE/RELAY BOX? THE RELAY CONTACTS CONTROL the coil circuit to the SOLENOID. Found this, but note no locks/ lock slots: https://www.ebay.com/itm/28410713443...d65bafe65ad740