That mystery grinding noise typically after a clutch job - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 10-20-2008, 08:31 PM   #21
Elite Member
Thread Starter
iTrader: (10)
 
rccote's Avatar
 
Join Date: Jan 2008
Location: Buffalo NY
Posts: 1,595
Total Cats: 17
Default

Quote:
Originally Posted by nicacus View Post
[COLOR=black][FONT=Verdana]Yeah I used the OEM jack that came with the car to push it up. It seemed to be a temporary fix though; the noise is back in full force. Mine is pretty damn spot on to the noise yours makes. I feel like a douche every time I get up above 3000 RPM people probably think my engine is about to explode.
Yeah that really is about the sum of it. Glad I'm not a special case and alone in this.

Quote:
Originally Posted by brgracer View Post
I've never had this issue with multiple clutch jobs, but technically, you are supposed to mark the driveshaft and diff and realign the exact same way.
Hard to do when you swap out your transmission, driveshaft, half shafts and differential all at once.

Quote:
Originally Posted by nicacus View Post
I am going to be putting a new high flow cat on later this week to see if it helps at all.
If it means anything at all my Hi-Flow cat is relatively new within the last year or so and the noise was present back then too.
rccote is offline   Reply With Quote
Old 10-20-2008, 08:39 PM   #22
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

Quote:
Originally Posted by rccote View Post


If it means anything at all my Hi-Flow cat is relatively new within the last year or so and the noise was present back then too.

****...
It's that damn voodoo box. I say we trick FM into fixing it
nicacus is offline   Reply With Quote
Old 10-20-2008, 09:21 PM   #23
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

Could it be from the pilot bearing not being pressed flush with the flywheel possibly maiking it wobble slightly??
My car makes the noise even if it is in nuetral and i rev it up.
nicacus is offline   Reply With Quote
Old 10-20-2008, 11:16 PM   #24
Elite Member
iTrader: (8)
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,732
Total Cats: 3
Default

Thought i'd chime in on this with my results...

I just went for a drive after realigning my ppf and the noise is just about completely gone. If I listen very closely I can faintly make out some of the noise still, but then again I used a tape measure and quickly converted MM to Inches in my head. My PPF is at 2 5/8" from the frame rails. I bet if I were more precise with it i could get rid of this noise 100%.
wayne_curr is offline   Reply With Quote
Old 10-21-2008, 03:37 AM   #25
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

Quote:
Originally Posted by wayne_curr View Post
Thought i'd chime in on this with my results...

I just went for a drive after realigning my ppf and the noise is just about completely gone. If I listen very closely I can faintly make out some of the noise still, but then again I used a tape measure and quickly converted MM to Inches in my head. My PPF is at 2 5/8" from the frame rails. I bet if I were more precise with it i could get rid of this noise 100%.

Tried that.. I used a ruler with millimeters and got it right at 65mm. It seemed like it helped at first but the noise is just as bad now
nicacus is offline   Reply With Quote
Old 10-21-2008, 02:13 PM   #26
Elite Member
iTrader: (8)
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,732
Total Cats: 3
Default

Upon more driving and closer listening this morning i can still hear it fairly clearly for about 200rpms between 3 and 4 but it is still a 95% improvement from before.

nicacus, try rotating your driveshaft on your diff like someone mentioned earlier. That sounded like a good idea to me.
wayne_curr is offline   Reply With Quote
Old 10-21-2008, 02:21 PM   #27
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

I am going to try that a bit later today.. but the sound is still there even if the car is in nuetral, right at about 3900RPM up until about 5000RPM I'm going to make a video today..
nicacus is offline   Reply With Quote
Old 10-21-2008, 02:45 PM   #28
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

Quote:
Originally Posted by nicacus View Post
I am going to try that a bit later today.. but the sound is still there even if the car is in nuetral, right at about 3900RPM up until about 5000RPM I'm going to make a video today..
If you are in neutral and standing still, most likely it is a loose heatshield or something in the exhaust(like a loose bolt that slipped into the downpipe) or a broken baffle.
olderguy is offline   Reply With Quote
Old 10-21-2008, 02:51 PM   #29
Elite Member
iTrader: (8)
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,732
Total Cats: 3
Default

Quote:
Originally Posted by olderguy View Post
If you are in neutral and standing still, most likely it is a loose heatshield or something in the exhaust(like a loose bolt that slipped into the downpipe) or a broken baffle.
I agree with this.

I dont believe your problem to be the same "mystery grinding noise" that i'm having. Mine is certainly not audible in neutral.

Good luck though!
wayne_curr is offline   Reply With Quote
Old 10-21-2008, 04:05 PM   #30
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

I cant find anything that is loose at all.. I have taken just about everything off and re-torqued it.

there is still the noise while in decel though. I have the video just need to wait until I get home to upload it.
nicacus is offline   Reply With Quote
Old 10-21-2008, 05:25 PM   #31
Elite Member
iTrader: (8)
 
Join Date: Aug 2007
Location: Bellingham, Wa
Posts: 2,732
Total Cats: 3
Default

Ok, drove around some more today. Its starting to get louder again, the noise is coming back.

I give up. I'll live with it...oh well. But why would it go away almost completely then start coming back?
wayne_curr is offline   Reply With Quote
Old 10-21-2008, 06:49 PM   #32
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

Possibly a bad universal.
olderguy is offline   Reply With Quote
Old 10-21-2008, 07:05 PM   #33
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,796
Total Cats: 247
Default

Wow this sucks. Now I'm scared to pull all my **** apart. When I do I'm gonna mark everything with spray paint before unbolting anything so I can reassemble it exactly the way it was before.
patsmx5 is offline   Reply With Quote
Old 10-21-2008, 07:17 PM   #34
AFM Crusader
iTrader: (18)
 
olderguy's Avatar
 
Join Date: Oct 2004
Location: Wayne, NJ
Posts: 4,438
Total Cats: 84
Default

Quote:
Originally Posted by nicacus View Post
I cant find anything that is loose at all.. I have taken just about everything off and re-torqued it.

there is still the noise while in decel though. I have the video just need to wait until I get home to upload it.
You indicate a Fidanza 8 lb flywheel in your signature. They are known to cause noise on deceleration.
olderguy is offline   Reply With Quote
Old 10-21-2008, 08:27 PM   #35
Elite Member
Thread Starter
iTrader: (10)
 
rccote's Avatar
 
Join Date: Jan 2008
Location: Buffalo NY
Posts: 1,595
Total Cats: 17
Default

Mine is audible in neutral too. Rev up to ~2k and let off it does it. Might try doing it with the clutch in and seeing if it makes the noise to rule out any other possibilities. I'm almost certain it has nothing to do with the transmission back. I'll haul out my recording equipment to my car and get a high quality sound clip when I have time.

What's really frustrating is that we've already eliminated so many variables and there's not a whole lot left. I haven't checked but I'm pretty sure I don't have the lightweight flywheel. The last guy raced it, and it's possible, but I'm pretty sure I don't considering I didn't have noises on decel when I first got it.

Heat shields don't seem to be the cause of it. Mine aren't loose, there's no rocks or anything lodged and the sound just isn't consistent with heat shields.

I've read that this is isolated to earlier models of NAs, typically 90s. What's the difference then between early 1.6 NAs to the later 1.8s?

Diff is out, drive shaft is out and transmission is out because A.) the noise can be produced in neutral ( drive shaft/diff is out ) and B.) this is the third transmission I've swapped in (unless all three of my transmissions we're fucked which I believe is unlikely)

Places I need to check: I've noticed both nicacus and I are running Voodoo II kits. Maybe our motor mounts are junked and the turbo happens to be rattling against the area that we cut and bent in to clear room for the turbo. Doubtful, but it's worth checking out.

Starter? It's constantly being run with the engine regardless of the clutch being in or out. Although I'm not sure why, given the conditions, it would make that noise.

As precisely as possible we need to find out where the noise is coming from and address any moving parts in that area.

Well, if we continue to rule out possible factors eventually we'd have to hit home, right?

Last edited by rccote; 10-21-2008 at 11:06 PM.
rccote is offline   Reply With Quote
Old 10-21-2008, 10:43 PM   #36
Senior Member
iTrader: (7)
 
nicacus's Avatar
 
Join Date: Jul 2006
Location: SLC UT
Posts: 1,133
Total Cats: 0
Default

I have new mazdaspeed motor mounts that are maybe 4 months old, I changed them right after I put everything back together because I thought they might be the cause of the noise.

I checked that area near the turbo as well it doesn't look as if it is coming into contact with it at all as there is no signs of rubbing or bumping. maybe it has something to do with the FM hardware?? But this didn't start to happen until I switched my motor/clutch.
Rccote do you have a shortnose crank? the motor I have now is a shortnose, maybe something is going wrong with it?? I have no idea..

I'm not so worried about the decel noise I can live with that. I have the video/audio. I just have to wait until I am home to upload it. probably not for another four hours or so.
nicacus is offline   Reply With Quote
Old 10-21-2008, 10:46 PM   #37
Elite Member
Thread Starter
iTrader: (10)
 
rccote's Avatar
 
Join Date: Jan 2008
Location: Buffalo NY
Posts: 1,595
Total Cats: 17
Default

I've got the SNC motor too. I've got no wobble so I think that's a not an issue currently.
rccote is offline   Reply With Quote
Old 10-21-2008, 10:54 PM   #38
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,796
Total Cats: 247
Default

Quote:
Originally Posted by rccote View Post
Mine is audible in neutral too. Rev up to ~2k and let off it does it. Might try doing it with the clutch in and seeing if it makes the noise to rule out any other possibilities. I'm almost certain it has nothing to do with the transmission back. I'll haul out my recording equipment to my car and get a high quality sound clip when I have time.

What's really frustrating is that we've already eliminated so many variables and there's not a whole lot left. I haven't checked but I'm pretty sure I don't have the lightweight flywheel. The last guy raced it, and it's possible, but I'm pretty sure I don't considering I didn't have noises on decel when I first got it.

Heat shields don't seem to be the cause of it. Mine aren't loose, there's no rocks or anything lodged and the sound just isn't consistent with heat shields.

I've read that this is isolated to earlier models of NAs, typically 90s. What's the difference then between early 1.6 NAs to the later 1.8s?

Diff is out, drive shaft is out and transmission is out because A.) the noise can be produced in neutral and B.) this is the third transmission I've swapped in (unless all three of my transmissions we're fucked which I believe is unlikely)

Places I need to check: I've noticed both nicacus and I are running Voodoo II kits. Maybe our motor mounts are junked and the turbo happens to be rattling against the area that we cut and bent in to clear room for the turbo. Doubtful, but it's worth checking out.

Starter? It's constantly being run with the engine regardless of the clutch being in or out. Although I'm not sure why, given the conditions, it would make that noise.

As precisely as possible we need to find out where the noise is coming from and address any moving parts in that area.

Well, if we continue to rule out possible factors eventually we'd have to hit home, right?
+131243885732343 We need video of this sound.

The starter engages to start the engine. Then it goes back to doing nothing. So it should definitely not be spinning when the engine is running.

What brand and weight of oil do you run? It's "known" that heavy oil shuts up loud transmissions, but then they don't shift as well when cold. You're running an expensive high quality synthetic right?

And some parts in the transmission DO spin when in nuetral. Like the input shaft.
patsmx5 is offline   Reply With Quote
Old 10-21-2008, 11:03 PM   #39
Elite Member
Thread Starter
iTrader: (10)
 
rccote's Avatar
 
Join Date: Jan 2008
Location: Buffalo NY
Posts: 1,595
Total Cats: 17
Default

Quote:
Originally Posted by patsmx5 View Post
+131243885732343 We need video of this sound.

The starter engages to start the engine. Then it goes back to doing nothing. So it should definitely not be spinning when the engine is running.

What brand and weight of oil do you run? It's "known" that heavy oil shuts up loud transmissions, but then they don't shift as well when cold. You're running an expensive high quality synthetic right?

And some parts in the transmission DO spin when in nuetral. Like the input shaft.
So the starters out then.

I'm running Royal Purple 75w-90 right now, Mobile 1 full synthetic on the second, and Redline on the first all and still had the issue. All three transmissions sounded exactly the same. The difference is now my tranny shifts like butter. Though, it's become a tiny tiny bit notchy at times. I might have to bleed my slave sometime soon.

Could we rule out the input shaft if the sound can be produced while sitting still with the clutch in (disengaged). I really want to rule out the transmission and move on to other areas.
rccote is offline   Reply With Quote
Old 10-21-2008, 11:08 PM   #40
Elite Member
iTrader: (15)
 
patsmx5's Avatar
 
Join Date: Aug 2007
Location: Houston, TX
Posts: 8,796
Total Cats: 247
Default

Quote:
Originally Posted by rccote View Post
So the starters out then.

I'm running Royal Purple 75w-90 right now, Mobile 1 full synthetic on the second, and Redline on the first all and still had the issue. All three transmissions sounded exactly the same. The difference is now my tranny shifts like butter. Though, it's become a tiny tiny bit notchy at times. I might have to bleed my slave sometime soon.

Could we rule out the input shaft if the sound can be produced while sitting still with the clutch in (disengaged). I really want to rule out the transmission and move on to other areas.
Yeah if the noise is there when the clutch is fully disengaged, then it's not the transmission.
patsmx5 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 57 07-19-2017 05:11 PM
1994 Spec Miata Race Car SM/SM2/SSM For Sale Quinn Cars for sale/trade 6 10-23-2016 08:58 AM
ACT race clutch and AASCO 7lb. aluminum flywheel graexodus Miata parts for sale/trade 5 10-26-2015 02:48 PM
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
Another Alternator thread ihiryu General Miata Chat 9 09-28-2015 11:22 AM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 10:30 AM.