1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Starter Motor Grinding Rocks

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Old Jun 12, 2023 | 12:21 PM
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Starter Motor Grinding Rocks

Before I buy a new starter motor, can you experts tell me if I missed something?

Turn the key and I get a horrible scary noise. Not the usual starting it in gear noise. Way deeper and slower. Sounds like I am grinding rocks in the engine. Car will not start. Hopefully the movie attached correctly so you can hear it, and see what the tachometer is doing.

Battery fully charged, 12.6v at terminals on multimeter.
Prior to problem starting, car was totally reliable for many months, first time starter every time hit annd cold after less than 2 seconds of cranking.
Previous start before problem began, I forgot to put the gear in neutral and car lurched forward a few feet under starter power.
Once problem began, was able to start the car three times but each time engine was warm. Once car started ran great, and drove a 200 mile 5 hour event.
Now the engine is cold and no start.

Had my eye on a spare tire subwoofer…. But there go those plans.


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Old Jun 12, 2023 | 12:31 PM
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Video with sound linked here.

https://youtube.com/shorts/d-LZGZR53Y4?feature=share
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Old Jun 12, 2023 | 01:00 PM
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Hard to hear the actual sound. I'd start by removing the starter and inspecting the pinion gear and flywheel teeth. Have the starter tested at your local parts store to isolate the problem between the starter and something else, which is what I suspect.
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Old Jun 12, 2023 | 05:46 PM
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Yikes, that sounds horrible! Almost like the starter mounting bolts are loose and it's skipping teeth when trying to engage. Looking forward to seeing what you find.
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Old Jun 12, 2023 | 05:52 PM
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Have the starter motor out. Bolts were tight, but was thinking along the same lines and half expected to find the starter hanging loose. Teeth look good. In my uneducated opinion. I am also British so not a good judge of teeth. Current theory is bad solenoid, maybe not throwing far enough to engage the teeth but enough to catch the edges and make that horrific noise. Off to Oreilleys to get it tested.

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Old Jun 12, 2023 | 06:27 PM
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I'm from West Virginia USA. When we want to pay a fellow West Virginian a complement we say "Nice tooth"

Good luck with your starter. I bought a reconditioned starter from Parts Geek that solved our problem.
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Old Jun 12, 2023 | 06:34 PM
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OReillys tested the starter. Solenoid is kaput. New one on the way.
glad it’s an easy fix. Really sounded like something had broken free and was pinballing around in one of the housings!
And yes, have been a victim of dental profiling more than once. I live in California, land of the dazzling smiles, which is unfortunate when you have classic British teeth.
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Old Jun 13, 2023 | 12:35 PM
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Fix did not work. New solenoid. Same horrible noise.

Next step new starter motor?

Seems logical but OReillys tested motor as good. Maybe something mechanically wrong in starter causing pinion to not push all the way into flywheel teeth?

Symptoms:
- When key turned, engine makes horrible slow grinding rocks noise and fan rotation appears to stutter rather than turn at even speed. See earlier link in reply string to YouTube video for noise.
- When starter removed an inspected teeth on starter pinion and flywheel teeth look good and pinion slides back and forth smoothly. Tested at OReillys, motor tested good, solenoid bad. Replaced solenoid.
- Starter is now bolted back in good and tight.
- Battery two years old, 12.6v.
- When problem first began four days ago I was able to start engine after a few seconds of grinding cranking and it ran really well. Now will not crank fast enough to start.

Last edited by Slow_sevens; Jun 13, 2023 at 12:58 PM.
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Old Jun 13, 2023 | 12:55 PM
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auto or manual?

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Old Jun 13, 2023 | 12:58 PM
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Good question. Manual.
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Old Jun 13, 2023 | 01:08 PM
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clutch dragging?... i.e leaving it partially engaged?

maybe a piece of it came apart and lodged in there.... hence sometimes it breaks free and seems ok.

I would try to get my eyes on the clutch and engagement mechanisms..... hopefully it has a removable front plate or something. I don't know that tranny model.
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Old Jun 13, 2023 | 01:21 PM
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Have you tried spinning the engine over by hand? Not to be a doomsayer but it's at least worth confirming that the engine itself isn't the source of crunchy load. And yes I know you said it ran even after the issue started, it's just an easy thing to check that can't hurt anything. I sincerely doubt it's the problem.

Assuming that the engine is all well, and I would think it is, I'd be leaning towards some sort of internal failure of the starter that only shows up under loading. If you happen to have a spare starter lying around I'd certainly give that a whirl. Other that I can't really say, but it almost sounds too slow to be teeth grinding.
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Old Jun 13, 2023 | 01:21 PM
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There's an inspection plate on top of the engine to check out the flywheel area. The opening where the starter goes should also provide a good view.

To eliminate issues upstream, can the engine turn easily by hand with a ratchet on the front pulley bolt? Taking out the spark plugs will make it spin easier.
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Old Jun 13, 2023 | 01:57 PM
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Before I replaced my starter I cleaned the pinion gear area with Berryman's parts cleaner and rinsed it well with gasoline, blew it dry with compressed air and lubed the shaft with a light oil. Worked great for several months. But, my problem was with the Bendix not engaging, your starter sounds different, but it's worth a try. Good luck.
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Old Jun 13, 2023 | 01:59 PM
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Originally Posted by j_tso
There's an inspection plate on top of the engine to check out the flywheel area. The opening where the starter goes should also provide a good view.

To eliminate issues upstream, can the engine turn easily by hand with a ratchet on the front pulley bolt? Taking out the spark plugs will make it spin easier.

guess you could also just put it in nuetral and roll rock/roll it some. that would also tell you if it is dragging for some reason. just throwing stuff out there.
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Old Jun 13, 2023 | 02:00 PM
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lube the shaft man!!! lol
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Old Jun 13, 2023 | 03:17 PM
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Good idea turning the engine by hand to check for worse case scenario. Tested it with ratchet on main pulley and turns nice and smooth with no catches or nasty noises. (Breathes sigh of relief). Clutch isn’t dragging, and had a good look inside the hole where the starter motor goes with an inspection mirror, and could see flywheel teeth are good and could not see any obstructions or anything rattling around loose in there.

Thought about jamming the starter solenoid in the pinion forward position to test theory that pinion is not pushing into the flywheel teeth…. But then see rebuilt starters are pretty cheap. So, rather than screw things up further going to order a starter and see if that fixes it. Not totally convinced as the mechanical pieces that throw the pinion forward all work when moved by hand, but maybe as you guys said it only happens under load.

Will report back in a few days.


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Old Jun 13, 2023 | 08:55 PM
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I think it would help if you take the video in the engine bay instead of the drivers seat while cranking. It muffles the sound too much. If the pinion isn't fully extending it should show up in the bench test. If it doesn't engage fully in operation due to some resistance you'd probably recognize the excessive grinding noise btw the pinion and flywheel. I'm still leaning towards some sort of other internal resistance. Do the alternator, air pump and AC compressor all spin free if you loosen the belts? Sounds like something is causing the fan to rotate erratically.
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Old Jun 13, 2023 | 11:07 PM
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I will loosen belts and give them a spin tomorrow. Don’t think I will find anything…. Alternator and fan were in play with belts at correct tension when I turned the engine by hand using a ratchet on the main pulley bolt… and engine, alternator and fan all turned smoothly together. But best to rule them out.
noise is heavy, hard and iron-like. Definitely something substantial.
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Old Jun 13, 2023 | 11:58 PM
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My money is still on the starter itself, especially since this popped up after trying to start it in gear. Nothing else should have seen any abnormal loads from such an event.

Will be curious to see what the new unit yields.
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Old Jun 14, 2023 | 10:47 PM
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Any possibility the ring gear came loose? I had that happen once. As I remember it was kind of intermittent at first. I don't remember a rock grinding sound, but I guess depending on the angle it takes when loose it might make that sound. It ended up getting tack welded in place. With the starter out, I think you should be able to pry on the ring gear to see if it is loose. Also might watch the ring gear while spinning the engine manually.

Just a thought.

Carl
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Old Jun 14, 2023 | 10:55 PM
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Good God! I had no idea that a ring gear coming loose could even happen! Certainly would fit the symptoms. But shouldn’t I have heard it banging around inside the bell housing the couple of times I was able to get the car started?

Will try the new starter first as an easy test. Current theory is that device that allows the starter shaft to spin freely when the engine fires up is letting go under starter load. Also fits the symptoms.

Starter arrives Fri and I will report back once installed.

Last edited by Slow_sevens; Jun 14, 2023 at 11:02 PM.
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Old Jun 14, 2023 | 11:00 PM
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Originally Posted by Carl
Any possibility the ring gear came loose? I had that happen once. As I remember it was kind of intermittent at first. I don't remember a rock grinding sound, but I guess depending on the angle it takes when loose it might make that sound. It ended up getting tack welded in place. With the starter out, I think you should be able to pry on the ring gear to see if it is loose. Also might watch the ring gear while spinning the engine manually.

Just a thought.

Carl
Funny you say that as I had been thinking the same thing. My prior reply was originally headed down the path of "nothing else should have seen any abnormal loads from such an event [starting in gear], other than perhaps the ring gear" before trimming it down. It seems like an odd noise for such a situation, but it's certainly something else to investigate. Thankfully if the ring gear does end up being the problem replacements are pretty easy to find.
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Old Jun 14, 2023 | 11:03 PM
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Agh! I have horrible feeling Carl is right. Now I think about it I tried to inspect the flywheel teeth through the inspection cover behind the rats nest. I couldn’t see the ring gear once I removed the cover but just assumed that I was looking in the wrong place, so checked through the starter hole and all looked good. Maybe the reason I did not see the gear through the inspection hole was because that part of the gear had broken off!

Will look again tomorrow once the sun is up.

Was hoping to never have to mate the transmission to the engine ever again. Done it twice, and both times I found myself questioning my life choices.

Last edited by Slow_sevens; Jun 14, 2023 at 11:14 PM.
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Old Jun 15, 2023 | 07:05 AM
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With the starter removed if you hold your head just right or use a mirror you can see the ring gear. I actually took a picture of it on mine, I just can't find it.
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