2cams70 wrote:Looking at the wiring diagram they have shown with the inertia solenoid still in place I'd say it's very dodgy. If wired this way start up of the motor and engagement of the pinion will both occur simultaneously - in which case you may as well still have an inertia starter, all the benefits of having a pre engaged starter are effectively negated.
not quite, the main advantage of pre engaged modern starter is the torque.
Understood, a minimal voltage drop is lost with 2 solenoids in series in my setup, but I like the idea of retaining a stock harness and not having a hot wire hooked up underneath in the warmth and oil of the engine (though I have also added a safety circuit switch on the trunk wall in case of an engine fire - so that is 3 contacts in series actually, belt and suspenders...).
I was initially a bit concerned with charging a LiFePo battery with a Lucas ACR alternator, even if endowed with a new regulator unit set around 14V (dynamo modification I had done before changing the battery) but it has been fine for a couple years now (I had the experience of having done that swap on my motorcycle, a BMW r90s, on which I had installed an uprated regulator a 14.2V and was fine).
Quoting from Dan's last post elements that raised my attention :
collins_dan wrote: Cleaned the earth in the trunk/boot, it was better, but still occasionally a problem.
That usually points to a wiring issue, probably oxidation at the chassis but I would check all wires and connections (I add contact grease when I do that) - which does not mean it is the only issue
collins_dan wrote: this was a challenge as the battery was old, so I got a new one. Problem basically went away, unless I was starting and stopping the car a number of times.
That was typical of a lead battery going weak, less current output capability and eventually voltage drop. That would add to a wiring issue, but is cleared now.
collins_dan wrote: I checked the ignition switch voltage using the ground under the dash to test voltage coming in, 12.5, and going out, 11.3. I replaced the ignition switch, but problem continues. Here's my struggle. The design is fine as it worked flawlessly for 13 years. Something has deteriorated over time, I will pull the starter and look to see if anything is blocking full engagement, but i think it is unlikely as the pinion on the old starter was perfect. I will check the engine earth. I think the jump wire test will reveal that if 12.5 volts goes to the starter it will work, as when the battery is fully charged, it works.
Before pulling the starter apart I would complete all electrical tests, esp. if indeed all works when the power is brought directly to the starter (jumper wire on the engine and solenoid output) then this would identify an electrical issue to be solved (poor contacts would be first on my list, but wire internal resistance can also give that kind of behavior, when copper is sufficiently oxidized inside the wire to let a small current go but not enough, thus exhibiting a non linear impedance).
collins_dan wrote:The thing I continue to not understand is why the voltage drop through the ignition switch.
Just to be sure of what is what, maybe you can post a photo of the switch explaining what/where are the wires you referred to previously (brown/blue, sizes etc) e.g. when you mention white/red wire coming from the ignition, I understand it is from the dashboard (it could be that the corresponding switch is internally oxidized also, or if helped by a relay that this relay has developed some carbon deposit over time, then the resulting current to the power switch would be too weak which in turn not let enough strength at the solenoid to get to cranking position). One test you can do is to bring a strong, solid hot wire to the output of that dashboard switch to see if you can manually operate the end of the circuit, in other words test each element individually (wiring included).