Another weird starting issue...

[MissouriLC]

A little over a month ago, I rebuilt my starter (Late-night starter replacement... - https://forum.ih8mud.com/threads/late-night-starter-replacement.1384788/#post-16422574), replacing both the contacts and the plunger. The started in question is a Denso remanufacture 280-0169. FWIW, I replaced my fusible link and junction block at the same time.

A week ago, I weird intermittent issue started. About once every 8 to 10 starts, the starter will crank a couple of times and then make a grinding sound--like when you try to start the car and it's already running. Sometimes the engine will catch just as this is happening. Sometimes I stop turning the key and then try it again, and it starts (albeit sometimes it starts a little hard as if it is flooded. It might be my imagination, but it feels like the started looses juice a little right before this happens. It's also fair to say that I am not SURE that the starting is grinding, but that sure is what it sounds like.

There doesn't seem to be any rhyme or reason to this (wet/cold/hot/etc.), only that I will typically get 5 to 8 good starts between any time this happens.

When I was chasing my original starter issue, I read up extensively on adding a relay/solenoid to goose the starter with higher voltage (94 delayed cranking. Starter, ignition switch, or other? - https://forum.ih8mud.com/threads/94-delayed-cranking-starter-ignition-switch-or-other.987114/). Consensus seems to be that the voltage from the ignition switch is just barely adequate to trigger the built-in solenoid on the starter, and with wearing contacts or older wiring with increased resistance, you get intermittent starting issues.

So please check my theory here and tell me if I am on the right or wrong track. If the starter is grinding while cranking, that means the Bendix gear is partially retracting. If this is what is happening, then it seems the cause would be weak signal voltage from the ignition switch, causing the plunger to disengage a bit and causing the Bendix gear to partially retract. It seems that this could be caused by signal wire voltage, and would likely precipitate erosion/wear of the contacts. Does that make sense, or am I completely off-base.

Based on that, the relay mod would eliminate the weak link of the old ignition switch signal wire.

Anyone else experience something similar? Any other possible issues I should look into?

 

[george_tlc]

The bendix is driven out by the 'post' on the plunger. If it is retracting, the plunger contacts would not be making electrical contact to energize the motor in the starter. I had squealing banshee sounds years ago due to a starter failing - it would do it once every bunch of times. Replaced the starter and the banshees moved on. Is your grinding sounds high pitched (banshee) or just nasty low frequency grinding?

In my case the contacts were in decent condition, it was something else mechanical causing the sound. Once the starter was replaced with a denso reman, the problem never returned. I have since replaced the starter once again due to intermittent start. Seems that the starters on the 80's (at least in my 97), last 5-10 years - obviously depending on how many start cycles they deliver.

When changing contacts/plunger, it is worth pulling the motor out and cleaning any debris in the commutator due to the brushes slowly wearing things. The manual has some recommendations and specs. Cleaning with fresh grease in the the starter 'gearbox' is also a good idea.

cheers,
george.

 

[MissouriLC]

The bendix is driven out by the 'post' on the plunger. If it is retracting, the plunger contacts would not be making electrical contact to energize the motor in the starter. I had squealing banshee sounds years ago due to a starter failing - it would do it once every bunch of times. Replaced the starter and the banshees moved on. Is your grinding sounds high pitched (banshee) or just nasty low frequency grinding?

In my case the contacts were in decent condition, it was something else mechanical causing the sound. Once the starter was replaced with a denso reman, the problem never returned. I have since replaced the starter once again due to intermittent start. Seems that the starters on the 80's (at least in my 97), last 5-10 years - obviously depending on how many start cycles they deliver.

When changing contacts/plunger, it is worth pulling the motor out and cleaning any debris in the commutator due to the brushes slowly wearing things. The manual has some recommendations and specs. Cleaning with fresh grease in the the starter 'gearbox' is also a good idea.

cheers,
george.

It's not a high-pitched squeal... its more of a medium pitch scrape/grind, like running a pencil point quickly against sandpaper.

 

[alia176]

this might be nearly impossible to catch on video but if you could pull that off, we might have a better feedback for you. Sounds like something to do with the rebuild gone a little wonky. FSM says to use a vice to squeeze things while tightening, which I assume you did but wanted to confirm.

The retraction of the bendix is due to the spring, from what I recall. The solenoid pushed it out when voltage is applied, the spring pulls it back when you let go of the key. Also, if the bendix is staying engaged with the flywheel teeth, then the starter is going for a ride once the engine fires up and idles, but it doesn't sound like that's happening.

 

[MissouriLC]

this might be nearly impossible to catch on video but if you could pull that off, we might have a better feedback for you. Sounds like something to do with the rebuild gone a little wonky. FSM says to use a vice to squeeze things while tightening, which I assume you did but wanted to confirm.

The retraction of the bendix is due to the spring, from what I recall. The solenoid pushed it out when voltage is applied, the spring pulls it back when you let go of the key. Also, if the bendix is staying engaged with the flywheel teeth, then the starter is going for a ride once the engine fires up and idles, but it doesn't sound like that's happening.

I did make sure to push the contact plates down when tightening the lug nuts… in fact, the old contacts that I pulled out were both tilted at an angle in there. Not sure if it came from Denso that way, or if they contacts were replaced once before, but they weren’t replaced to Toyota FSM spec!

It’s not hanging after start. If anything, it feels like it is retracting a bit during cranking, but I’m not even sure if that is mechanically possible.

I’ll try to take a video at every start and see if I can catch it!

 

[efjayatee]

I bought an ACDelco starter 2 yrs ago and It was the plunger not retracting and making contact to the flywheel for me. The sound is an unsettling "grinding" so i returned it and replaced it with a Denso and works as it should.

I thought of rebuilding the OEM at 1st but at $120 new for ACDelco and $135 Denso....I punked out.

 

[MissouriLC]

Alright, I finally caught it on video. It took 19 good starts, each one recorded, to get a bad one! (Hopefully these video attachments work.)

The first is a good, normal start. A/C is off, blower is on low, windows closed:

The second is where it makes the sound. Same conditions as above:

Its a little hard to hear, but you'll hear it crank about five times and then you'll hear a pop or bang right before it catches. In the car, there is a definite "CHHHH" sound on top of the bang, but it doesn't come through in the video, unfortunately.

As always, any and all insights are appreciated!