My starter died a couple weeks ago and I replaced it with a reman high output starter from my local parts store. Everything went in easy and it work perfect for about 40-50 starts then I heard a really bad grinding noise all of a sudden while idling in traffic. It only happened in R, D, 1, 2

I pulled the starter and the flexplate teeth aren't damaged. I got another unit from a different supplier and it made a less dramic grind when I started it up. Removed it again and added a couple shims. Didn't hear anything when I started the car but about 3 minutes into moving it around I could hear a faint grind from the flywheel/starter again. Do I need keep adding more shims until I get the proper clearance? Not sure what happened here since it was working fine before.

both are a reman acdelco unit. I compared them to the one I pulled out and its the same as far as it looks.

 

I don't understand the first issue. Are you saying the starter activated in 1 2 D and R but not in P or N? Is the second starter doing the same thing or or just grinding when activated to start?

 

When I start the car it fires right up like it should and there is no noise in Park or N. Once I shift to R, D, 1 or 2 I hear a continuous grinding from the starter. The second starter is doing the same thing as stated but the grinding is not as loud.

 

I was able to record a video. You can hear the difference between P and being in gear.

 

If the noise occurs when the starter isn't engaged it isn't a shim problem. Have you tried running it with the flywheel cover removed?

 

You need to see if the there is power on the purple wire to the starter all the time or if the starter is actually activated when making this noise. Check the clearance of the starter drive to flexplate.

 

I have not. Today was the first time I removed the cover to reinstall it but I did not run it without the cover. As mentioned when I test started it I didn't hear the noise at all. Once I backed it out my drive way to the street I heard it come back like the video above.

Does it sound like it's something w the starter and flexplate or could it be an issue with the transmission itself?

I will double check the purple wire voltage this week. What could cause the starter to not disengage?

I will check the clearance as well.

 

How do you know the grinding noise is from the starter?

Assuming that it is, the only way for a starter to make noise when it isn't engaged is that the starter drive is dragging and not fully retracting. Could be a burr on the starter shaft, could be a bad starter drive, could be a problem with the pole piece hanging up in the solenoid, could be a broken spring in the solenoid, could be a bad pivot mechanism on the pole piece.

 

Try running it with the cover off.

 

Fly wheel loose maybe~

 

Watching/Listening to the video, along with your comments, my gut feeling says it's an alignment issue - but obviously it could be any of the above suggestions, as well. Just so we're on the same page, it 'appears' (watching the video) you have an automatic transmission (flex plate) as opposed to a manual transmission (flywheel). The fact you cannot hear grinding when either in Park or Neutral suggests the starter pinion gear teeth are retracting back into the starter along the bendix - at least you don't hear the grinding sound when the vehicle is not under load (e.g. in any gear). The sound only appears when you engage the transmission (as you stated). Watching the video there appears to be modest downwards movement of the entire engine & transmission once engaged in gear. This suggests, to me, it's an alignment issue. It's such a PITA to diagnose/address this issue; but, at any rate:

(1) Double-check to ensure you have the correct starter for your vehicle & the correct solenoid.
(2) Did the starter come with a new solenoid or are you using a different solenoid? It would 'appear' the solenoid is sufficient to retract the pinion gear back into the starter as you clearly have no grinding in either Park or Neutral, only when placed into gear.
(3) Did you use original starter bolts or replace starter bolts with new bolts? They should be 'starter' bolts. Did the new starter come w/ new starter bolts? Sounds like this wouldn't make a difference but starter bolts have a specific shank diameter and knurling to position the starter and keep it from moving while torque is applied & thereafter.

I'm more or less hedging on an alignment issue.

 

That doesn't sound like the starter grinding. Something else is doing it. The dust cover on a jet-a-way is plastic so it's probably not that.

I'd go with the loose or cracked flexplate

 

I am just assuming it is related as that was the last part changed out 2 weeks ago and all the noise if coming directly from the flexplate area.

I will try that next. I was working by myself so it was hard to inspect while the car ran.

Yes, you got it correct. I only hear it when it engages into reverseor drive. The replacement I put on 2 weeks ago didn't have any issues at all and it started randomly while idling in traffic last week. The starter motor and solenoid are new. I used the original bolts but added a couple shims yesterday to try out.

I got rid of the Jet a Way 6 months ago and put in a built TH400 w shift kit.

 

Couple more videos with the dust cover removed. Start is engaging properly. You guys think the flexplate is loose or the teeth are grinding against the starter housing?

 

Sounds like transmission to me. Considering it's only doing it when you put it into gear. Is it was the starter or flex plate those would make noise all the time the only thing changing between park and drive is the redirection of fluid in the trans. Just my 2 cents.

 

Oh geez I hope not. I only put 200 miles it since installed.

 

My thoughts are that it's a loose or cracked flex plate. Because of this as soon as it's put in gear it causes the flex plate to rub up against something.

 

Torque converter itself as opposed to the transmission internals maybe? Redirection of fluid is handled by the TQ stator I think? I've replaced several TQs but not a knowledgeable trans person.

 

I will check the flexplate bolts when I get a chance later this week. Its been 114 here during the day lately.

@oldcutlass Is there anyway we can move this thread to the transmission section in the meantime until I get everything looked over again. Maybe someone there has experience the exact issue?

 

You can loosen the tq. Converter and slide it back so it does not rest on the flex plate start it and see if it does the noise when In gear . As mentioned by vintage chief the torque converter is probably the culprit. It's the only component moving when the car is stationary but put into drive or reverse etc etc.

 

I will try this next over the weekend. I appreciate everyones comments and advice.

 

I'm not sure what this will prove. If you unbolt the converter, then you never load the crank and thus never get to the conditions that cause the noise. The one thing you can check with the converter unbolted is see if the flexplate is cracked or loose.

 

Drop trans pan if you dont want to pull trans out. If it was mine I would do that. I would think metal would be inside. Internals or torque converter? If starter then metal shaving should be showing up or after shut off the starter shaft, gear drive would be red hot from spinning long term with no lubricate.

 

Joe the only reason I said to unbolt the converter was to see if there was any change in noise. Simple enough to unbolt the converter and see if there is any change.

 

But if there's no noise in Park and Neutral, then unbolting the converter means that it's always in "neutral" as far as the engine is concerned.

 

I get where you are coming from but from a basic might as well just do it perspective it wouldn't hurt or kill much time. Just to see what happens. But again underload seems like torque converter to me unless the crankshaft has walked that much. Or when the converter was tightened up it pulled away from the splines which loosening up the converter would show you that. I have had to shim the converters before and actually asked about that here like 10 years ago.

 

I can tell you right now that if you unbolt the converter, there won't be any noise. What will that tell you? The cause can still be either the trans or the thrust bearing in the engine. With no load on the crank, you won't know which it is.

 

I'm not disagreeing. I'm just saying it wouldn't hurt. But with the torque converter off you could rev the engine and rule out the crank to a degree.

 

It doesn't hurt, but it doesn't help either. It's just wasted effort. If you rev the engine and don't hear a noise, what does that prove? You aren't putting any load on the thrust bearing without the trans connected and in gear. As I said above, the only thing unbolting the converter does is that it lets you look at the flexplate for cracks.

 

I discovered the grinding noise goes away when the car is moving. Putting it drive and letting roll down the street I didn't hear anything until I stopped then it slowly came back until I started moving again. Not sure if that points to anything.

 

I was going to more or less make this suggestion earlier in the thread as a test run to see if the noise occurred during certain run conditions - which you still may want to try.

(1) Does the noise occur during a heavy (loaded) take-off condition when the car is stopped? You don't need to perform a hole-shot and rotate the rear tires, but put it under some load when you take off & see if the noise appears during the heavily loaded take-off from idle and gradually disappears as you move into cruise.
(2) Have you tried to brake torque the engine/transmission when stopped to see if the noise appears? IOW, the noise appears at idle (in a stopped condition), then when you brake torque the engine/transmission (in a stopped condition) does the noise disappear as the RPM increases?

 

It does not make any noise while under heavy load. The trans feels strong as it did and shifts fine. Check out the video below.

I have not tried to brake torque yet. Just discovered this a bit ago when I had a few min to test it out

 

Thanks I had to re-upload it. I posted it above.

 

No worries, glad you fixed the link.

 

And, an additional test would be to achieve a speed of 35mph - 40mph and shift into neutral (coasting). Is there ANY difference in sound - even the slightest you can decipher? I can almost hear the slightest of grinding even when you were just barely rolling in your video - maybe it's just me, but I think I can hear a modest grinding which worsens as you approach a stop. How about the same type video but when you stop, place the transmission in either Neutral or Park so we can listen (since Park or Neutral there was no discernible noise).

 

Known

Condition: Idle (Neutral/Park while stopped) = No Grinding
Condition: Idle (In Gear, Brakes applied while stopped) = Significant Grinding
Condition: Rolling Speed, In Gear (3mph-4mph) = No (Limited/If Any) Grinding
Condition: At Idle with Brake Torque Applied = ???? (Possible Outcome = As RPM increases during brake torque event, Grinding stops)

When you attached the TC to the Flexplate did you use Loctite? Did you use original bolts, new bolts, bolts from the TH400, torqued to specs? If no Loctite, marginal on torque specs or poor bolts the bolts may be loose.

 

That is all correct. I actually had a reputable transmission shop do the swap for me about 4 months ago. Not really sure on how they handled it.

 

Keenly awaiting the brake torque test - should only take a minute.

 

Sounds like an electric RC car

 

So, the grinding sound completely disappears during a brake torque condition. IOW, with the left foot holding the brake, right foot increasing RPM, the grinding completely disappears. That is what I heard in the video. Is that what you can confirm, as well?