91 2.3L Ranger intermittent no start.

Greetings I have a intermittent starting issue and I'm not sure what to target first. It has happened twice now, but its not clear to me on the cause. When it happens there is a single audible click that seems to be the sound of the starter hitting something, but failing to crank. Misalignment with the flywheel? Anyways the first time it happened I had a co-worker attempt to help me jump it which seemed to fail, but after a few attempts it started up fine. I took it to an autozone and they tested the battery & alternator giving it a clean bill of health. I have driven it at least 30 or so times since then with no issues. This time around jumping it didn't have any success so I came back with a multimeter and was able to verify the battery was showing 12.24v. I attempted to bypass the solenoid on the upper wall of the passenger side by shorting the posts with a screwdriver. After that failed I attempted to tap the starter while having a co-worker attempt to crank. Same single click noise with no change. We decided to attempt a push start and after a partial success (seemed it was about to start, but failed) we tried to crank it and it started right up. I noted mild hesitation on the initial part of the drive home, but its an old truck with 500k+ miles so its hard to tell if this was really out of the norm. After arriving home I tried to turn it off and on about 10 times without a single issue.

A few questions I have outside of being open to any suggestions.
- Can a push start attempt effect a starter in a similar manner to the "tapping" method?
- Can a bad ground cause symptoms like this?
- If I decide to replace the starter does it have torque specs and are they critical for that replacement?
- Any general recommendations on repair manuals?

Background on whats been done in the 3 years I have owned this regret of a truck:
- Transmission was rebuilt by a shop.
- Fuel pump has been replaced.
- Shocks and front lower ball joints.
- Spark plugs and cables have been replace.
- O2 sensor replaced.
- Breaks and new e-brake cable.
- anti-lock break sensor replaced. (still doesn't work)
- Temp sensor replaced (still don't trust what the dash shows)
- Throttle position sensor replaced.
- Catalytic converter replaced.

I had issues with the 5th, reverse gear before the transmission rebuild. After that I had issues with engine hesitation, failing to stay on, poor idling that were intermittent. After throwing a lot of the parts listed above and regular fuel system cleaner treatments at it that went away. It also still pours out grey/white exhaust when I first take off, after it heats up its fine. That is a side item I need to figure out before emissions in june.

Welcome to TRS~!

The most common cause of that symptom is a bad ground on the starter circuit. The wires get corroded on the inside or there is just a loose connection somewhere. No real way to test it other than to inspect, clean, tighten or replace the wire harness.

I'd suggest that before doing anything else...especially when it is sporadic...that usually means you have a loose wire somewhere...even the boot on the solenoid can become corroded and work sporadically and that wire allows the ignition to supply power to the solenoid which then drives the starter.

Thanks for the quick reply Mark I cleaned the wires connecting to the battery, but have not done so on other connections. They look to be original or at least worn enough to be original. I guess another question that comes to mind is if there is a way to diagnose the wiring with a simple multi-meter. My current understanding is that there isn't a reliable way to do this without better equipment. A question I forgot to post originally is what would be an acceptable battery drop when attempting to crank?

You're welcome...

Can't say that I've ever seen voltage numbers on battery drop during a start if that's what you are looking for. I do know that when the truck is starting the voltage should drop and if the truck doesn't start on the first crank the voltage should remain or quickly climb back to the original voltage before starting.

A healthy battery should show voltages of between 12.3 and 12.8 and if it gets below 12.3 it likely won't start the engine and should be replaced if after charging it cannot maintain that level as a stand alone. If there is a battery drain somewhere that could explain why the battery doesn't start, but the fact that it does start as you say tells me the ground or wires is likely the problem.

If the starter clicks with the key but does not engage the starter try jumping the solenoid. If that works then the problem is between the key and the solenoid (generally). If not then wiggle the wires and try the starter again...if that gets it to start then likely that is where the problem lies.

I'm not exactly sure of all the tests that can be done on specific wires...but there likely is someone on here that can elaborate...

I think if cranking voltage stays above 10v you are OK.

Given the vintage & miles, I would suspect the flywheel ring gear teeth or the starter pinion gear teeth being worn or damaged. If the teeth are 'burled' over enough, they find it hard to mesh properly, and the starter gear teeth can clank into the flywheel teeth and just make noise.
If you remove the starter and inspect both sets, you'll likely find some bad looking teeth. It happens over time. And you can also find some are worn more than others, explaining it working fine on Tuesday, but failing the next time you try.
To check w/o removing the starter, get a socket and breaker bar or ratchet, and turn the crankshaft a bit when it won't start. You may be able to roll it over by just grabbing the alternator pulley given the miles and how loose things get. You just want to move it enough to present different teeth to the starter gear when it is thrown against the flywheel. If it then starts normally, I would remove the starter and inspect both sets of gear teeth. It is a boring task, but it is worth rolling the crank through one turn to see them all, or if the starter gear is bad, just get a new Bendix drive. You'll need to remove the 'nose' end of the starter to install, but you do not have to remove the armature & brushes.
tom