AMC Eagle Den Forum

The Shop => Transmission Shop => Topic started by: ammachine390 on August 07, 2012, 01:47:49 PM

Title: Another weird noise
Post by: ammachine390 on August 07, 2012, 01:47:49 PM
So my Concord started making another weird noise. I'm pretty sure it's from the transmission. It's making a rattling noise at idle, no matter what gear it's in. Was running fine yesterday, then turned it off for a minute, when I restarted it, it was making this noise. I took the inspection cover off, and none of the teeth on the flexplate look damaged, also when the inspection plate is off, the noise is NOT any louder. Only thing I can think of is a torque converter issue, could it be coming loose? Car still drives fine, but I'm avoiding driving it as much as I can.

Here's a video, the noise is most audible at 36 seconds (but its there the whole time).
http://www.youtube.com/watch?v=Us5oZAwS4is&feature=youtu.be
Title: Re: Another weird noise
Post by: shaggimo on August 07, 2012, 04:53:58 PM
I too have a mystery rattle in the 84, have yet to pin point. Do you still have a catalytic converter in place? On mine I was leaning towards it being the culprit, the noise is only at low idle (or about to die, lol) and non metallic. Just a thought btw.
Title: Re: Another weird noise
Post by: mudkicker715 on August 07, 2012, 05:57:31 PM
My concord has an exast rattle at idle. I never tried to fix it yet
Title: Re: Another weird noise
Post by: ammachine390 on August 07, 2012, 09:05:42 PM
While it does have an exhaust leak, I believe this is a separate issue. Maybe it is just an exhaust leak, but it really sounds like its coming from the transmission.

Shaggimo, it does still have the catalytic converter, but the exhaust pipe does not seem to be ratting around. I grabbed it when the engine was idling, and there was very little to no vibration in the pipe.
Title: Re: Another weird noise
Post by: txjeeptx on August 07, 2012, 11:44:27 PM
Good video for diagonosis/guesswork help. My vote is for a crack in the flexplate between the torque converter and the crankshaft. Its a common problem for older AMC/Jeep flexplates. Should have put it in gear to see if/show if the rattle gets louder when loaded up.
Title: Re: Another weird noise
Post by: ammachine390 on August 08, 2012, 12:36:04 AM
Quote from: txjeeptx on August 07, 2012, 11:44:27 PM
Good video for diagonosis/guesswork help. My vote is for a crack in the flexplate between the torque converter and the crankshaft. Its a common problem for older AMC/Jeep flexplates. Should have put it in gear to see if/show if the rattle gets louder when loaded up.

Would that be noticeable to see with the inspection cover off? I'll upload another video tomorrow with it in gear.
Title: Re: Another weird noise
Post by: ammachine390 on August 08, 2012, 02:19:21 PM
Here's some pics of the flexplate. What do you all think?
(http://i815.photobucket.com/albums/zz79/ammachine390/IMG_0685.jpg)

(http://i815.photobucket.com/albums/zz79/ammachine390/IMG_0688.jpg)

Title: Re: Another weird noise
Post by: DaemonForce on August 09, 2012, 02:05:45 AM
Yeah my vote is cracked plate. I have a spare but it's rusted and I'm not sure what condition it's really in but when your plate cracks 100% you're not going anywhere.
Title: Re: Another weird noise
Post by: txjeeptx on August 10, 2012, 12:45:41 AM
2nd pic looks like a crack along where the bold is. Never any fun finding somethin like that, since it means a lot of heavy lifting is in the future. You might have a pro trans mechanic/shop have a look at it to confirm a crack, or you can confirm it yourself if you can feel along the bolt and can tell if there's something there where you can see the stains. If you can catch your fingernail on the surface, there's a crack there.

If you decide to tackle the transmission yourself, remember to remove/drain the pan before pulling it, or have a ton of rags handy for the spilled atf that will come pouring out. Nevermind, just have a ton of rags. It'll be messy. Also, the pain of removing the top bolts is eased with proper extensions and universals to reach waaaaay up there. Its a tight fit, the trans and the floor/firewall.
Title: Re: Another weird noise
Post by: ammachine390 on August 12, 2012, 01:23:52 PM
Well, I brought it to a trans shop on Thursday for the flex plate. They called me on Saturday morning, saying while the flex plate was cracked, it was not the source of the ticking noise. I dropped by the shop to take a look, and half of the torque converter neck snapped off. They said the trans needs to be rebuilt, and quoted me 1600......
Title: Re: Another weird noise
Post by: TheWraith on August 13, 2012, 07:15:32 AM
I just paid $1500 to have a tranny from a '98 Olds rebuilt...and that was with me taking them the trans (already out of the car)...and that was a 'good deal' looking at what others charge.  If the price they gave you is with them removing it and reinstalling it, then I can see it.  Not saying it is easy to write that check, but I could see it costing that much.

If it is running and driving, then why does it need to be rebuilt?  Can't the converter and flex plate be replaced without a rebuild?

Other then the noise, how is it driving/shifting/etc...?
Title: Re: Another weird noise
Post by: ammachine390 on August 13, 2012, 11:14:01 AM
Quote from: TheWraith on August 13, 2012, 07:15:32 AM
If it is running and driving, then why does it need to be rebuilt?  Can't the converter and flex plate be replaced without a rebuild?

Other then the noise, how is it driving/shifting/etc...?

That's what I thought too. Half of the converter neck snapped up, and they said that it got ground up by the transmission, so there was a lot of metal shaving in the trans, which they said was why it need to be rebuilt. It was driving and shifting fine. I would agree that it seems that just the converter and flex plate could probably be replaced. However, the tail shaft was loose, and it was leaking some transmission fluid, so that should be all fixed now too. Also, they are going to flush out the lines and the cooler.
Title: Re: Another weird noise
Post by: carnuck on August 16, 2012, 12:42:57 PM
Too bad you didn't have time to score an FSJ 727 to upgrade while they were doing it (direct swap)