Results 1 to 31 of 31

Thread: Noise!

  1. #1
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default Noise!

    Hello all

    Yesterday evening my Z began making an increadibly loud and very annoying rattling noise from the rear of the car. I can't remember exactly what time it began but it has, for what I can tell, become worse. The noise, the best I can describe, sounds like, well if you left the door ajar and it was rattling. It does it, really randomly, but when the road is uneven and bumpy the noise is always there. I've jack the back of the car up and shook, moved and really done anything and everything to get the noise to occur but nothing. I took the rear pannel off to discover that the antenna was, well just hanging there and in pieces. I fixed this thinking it was the noise but nope.

    I've jumped on the car and pushed the car up in an attempt to get the noise to occur but still nothing. I have noticed that the rear left - the area where the noise is coming from - tire does drop a bit further down then the right side. I've looked at the strut mount from both the top and felt it on the side, its still there for what I can tell and in one piece. Does anyone have ANY ideas what this can be? Blown shock? Any ideas. I run eibach lowering spring all around and tociko blues. I did the suspension two and a half and 15,000 miles ago.

    Thanks guys
    Jan
    1976 280Z
    HLS30288273

  2. #2
    Registered User Oiluj's Avatar
    Member ID
    CZCC-15388
    Join Date
    Nov 2007
    Location
    SF Bay Area
    Age
    66
    Posts
    1,746

    Default

    Sounds like a loose exhaust, but also look at the strut bolts to see if they are loose. They can "feel" tight with the weight of the car on them, but on the road make noise as the weight changes over bumps. Could also be a failed upper strut mount or a failed shock.
    Julio
    1972 240Z (in-progress, 95% complete)
    CZC# 15388

  3. #3
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Oiluj

    Checked the torque on all the bolts on the inside, both the mounting bolts (25 lb ft) and the strut lock nut (the big ass one 60 lb ft). Nothing still there. Check the exhaust by moving it every direction I could think of, nothing. I put the Z on the jack again (lifted it by the diffy) and moved the left tire and wheel around in every manner I could think of. I've never had a car with struts, could the shock be completely dead already? I mean I'm pretty hard on my suspension but 15k is pretty low on shocks isn't it? Is it safe to drive it like this? I mean I have to drive like 200 miles tomorrow for a wedding, its not going to kill something is it?

    Thanks
    Jan
    1976 280Z
    HLS30288273

  4. #4
    Registered User olzed's Avatar
    Member ID
    CZCC-20649
    Join Date
    Dec 2009
    Location
    Auckland. New Zealand.
    Age
    76
    Posts
    1,069

    Default

    Wheel bearing perhaps.???

  5. #5
    Registered User madkaw's Avatar
    Member ID
    CZCC-7622
    Join Date
    Dec 2004
    Location
    bloomington IN
    Age
    57
    Posts
    2,288

    Default

    Noises are always a pain because the noise can travel around the car and mislead you. Sounds like a loose strut , but you said the gland nut was tight. Not sure if a bad shock would produce a rattle sound. When you installed the struts you were SURE the and nuts bottomed out on the shock and not the threads on the nut. Not sure why you would just now start hearing the noise, but that's what it sounds like.
    I've noticed that it takes very little movement on any part to produce noises on these cars. A diff mount bolt on the moustache bar will cause a clunk if its a half a turn loose.
    Anyway it could be your hatch adjustment is loose and the hatch is rattling.
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

  6. #6
    Registered User siteunseen's Avatar
    Member ID
    CZCC-24724
    Join Date
    Jul 2011
    Location
    Alabama
    Posts
    1,967

    Default

    Like some comedian said, be glad your not in an airplane when you hear a bump. Cars you can pull over and fix it with a coat hanger.
    1972 240Z #918 New Sight Orange
    1977 280Z #305 Light Blue Metallic
    1972 240Z #110 Persimmons Red

  7. #7
    Registered User rcb280z's Avatar
    Member ID
    CZCC-21454
    Join Date
    Apr 2010
    Location
    Ventura Ca.
    Age
    57
    Posts
    873

    Default

    I remember chasing a rattle and it took a few days to find it. Ended up being the wood flap (can't remember proper name) that covers the spare tire. Somehow one of the felt strips had fallen off and it was rattling around on the metal bracket.

  8. #8
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Thanks mates

    What confuses me is that it just started out of the blue. I mean if I had a loose strut mount, or loose bolts or loose gland nut (which is tight also) I would think this noise would have been on going for a while now, as its been 2+ years. I've tried shaking the crap out of the car while it was on the ground to reproduce the sound (lifing it up and down side to side etc). With no luck. I'll jack the back end up again today before I go on my trip and make sure all is tight. The sound, sounds more like the hatch is loose or something and no a suspension issue. I'll see what I can find.

    Thanks
    Jan
    Last edited by Pomorza; 07-13-2013 at 10:03 AM.
    1976 280Z
    HLS30288273

  9. #9
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Ok update.

    I took literally everything out of the rear of the car, the spare tire, the hatch support from that side and anything loose that was in the back. The sound is still there. I do have a question, it if was indeed the struts wouldn't it feel different then all the other sides? I mean I went around my car and lifted each side the same height ~ 3 inches and let it drop. All four corners had the same rebound point. Madkaw, if the strut mount was bad or the strut wasn't bolted all the way wouldn't I be able to move it with the car in the air, at least some amoutn? I mean I was yanking the crap out of this suspension yesterday, to the point where it nearly fell off the jackstands. The rear seals on my Z are pretty, er..no existant so could it be that? I'm going to have the hatch off here in a few weeks to do them, whats the best way to make sure its lined up correctly?

    Thanks
    Jan
    1976 280Z
    HLS30288273

  10. #10
    Registered User madkaw's Avatar
    Member ID
    CZCC-7622
    Join Date
    Dec 2004
    Location
    bloomington IN
    Age
    57
    Posts
    2,288

    Default

    When you say rear seals, your talking weather stripping right?
    If they are gone, then the hatch could have play in it. The hatch should be a spring fit on the seal. I would adjust it down tight on the latch so it takes some force to latch and see if that changes anything.
    Nothing has to be too loose to make noise, so you don't always feel anything when you yank on it. It's hard to duplicate driving conditions. All the strut has to move is a 1/32" and it would make noise.
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

  11. #11
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Yes by seals I mean the weatherstripping. Its farily bad on the very rear (dead in the center) I can see day light out of it when the hatch is closed.
    1976 280Z
    HLS30288273

  12. #12
    Registered User
    Member ID
    CZCC-3609
    Join Date
    Feb 2003
    Location
    Clearwater,Florida USA
    Age
    75
    Posts
    4,424

    Default

    Take a torque wrench - and tighten the two big nuts - which should be on big washers - that hold the differential to the mustache bar. If they are at all loose.. it will make a pretty loud noise.

    FWIW,
    Carl B.

  13. #13
    Registered User EuroDat's Avatar
    Member ID
    CZCC-26512
    Join Date
    Feb 2012
    Location
    The Netherlands
    Posts
    1,420

    Default

    Carl's tip about the mustache bar bolts is a good one. They were the cause of a rattle that took me months to find.

    One extra note. Nothing to do with the rattle.
    The rear hatch seal should be replaced for your own safety. Carbon monoxide poisoning can be a risk if it lets exhaust fumes in the cabin.
    Chas
    Chas
    5/77 280Z HLS30 403100 with some modifications
    Original colour: 305 Light Blue. The PO changed it to Red

  14. #14
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    So I did notice one thing this morning while under the Z. One of the four bolts that is on the suspension (see photo, they right above the two huge nuts there) is not there as in gone. Does it matter what bolt goes here? What should the toque be on siad mustach bar bolts?.

    http://www.zforceproductions.com/pro.../IMG_13261.jpg
    1976 280Z
    HLS30288273

  15. #15
    Registered User madkaw's Avatar
    Member ID
    CZCC-7622
    Join Date
    Dec 2004
    Location
    bloomington IN
    Age
    57
    Posts
    2,288

    Default

    Does it matter!?!?!?
    YES- more importantly , I would not drive without it. You need to put a wrench on every bolt under your car. Get a bolt the correct diameter so there's no slop in there. Pretty good chance you found your rattle
    Steve
    71 240z,bw-5sp 2.4-40 over,balanced,e-88,big valves,ported&polished, stage2,header, triple Mikuni's 40's
    3.90 Subaru STI LSD

  16. #16
    Z geek at large FastWoman's Avatar
    Member ID
    CZCC-19635
    Join Date
    Jul 2009
    Location
    Hampton Roads, VA
    Posts
    2,787

    Default

    That's almost certainly the problem. However, I'd also not drive the car long distances without the hatch weather stripping, at least without the windows rolled down. That just invites carbon monoxide into the cabin. (It gets sucked inside from the turbulent air just behind the car -- common route of entry.)
    My last three sports cars while I still owned all three:

    2001 BMW Z3 Roadster 3.0i soft/hard top (sold)
    1966 Ford Mustang Coupe (sold)
    1978 Datsun 280Z (enjoying very much )

  17. #17
    Registered User LeonV's Avatar
    Member ID
    CZCC-19146
    Join Date
    Apr 2009
    Location
    Bay Area, CA
    Posts
    1,961

    Default

    Quote Originally Posted by FastWoman View Post
    That's almost certainly the problem. However, I'd also not drive the car long distances without the hatch weather stripping, at least without the windows rolled down. That just invites carbon monoxide into the cabin. (It gets sucked inside from the turbulent air just behind the car -- common route of entry.)
    Rolling the windows down makes it worse, as that lowers the air pressure inside the cabin making it even easier for fumes to get in. Driving with windows up and fan on is a better choice. FWIW...
    2/74 260Z

  18. #18
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Ladies and gents

    I'll get under the car sometime this week and tighten everything down. I do think that my mount might be back as the noise seems to occur under decompression (when I brake for instance). As for the weather stripping. I usually run with both windows down as its 100+ outside and I do not have AC.

    Thanks
    Jan
    1976 280Z
    HLS30288273

  19. #19
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Update part three

    I retorqued all the bolts on the rear suspension this afternoon per measurements given in the FSM. The noise is still there. There is a bit of an interesting development. When someone else is in the car - more weight - the noise is very seldom. The second it is just me the noise happens nearly everytime I hit any sort of bumps. This past weekend I also replaced the rear weatherstripping on the hatch. It's quite sealed. I did find some nasty rust in the process but at least now I know where I have rust and why.

    Any suggestions would be lovely

    Thanks
    Jan
    1976 280Z
    HLS30288273

  20. #20
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Update part three

    I retorqued all the bolts on the rear suspension this afternoon per measurements given in the FSM. The noise is still there. There is a bit of an interesting development. When someone else is in the car - more weight - the noise is very seldom. The second it is just me the noise happens nearly everytime I hit any sort of bumps. This past weekend I also replaced the rear weatherstripping on the hatch. It's quite sealed. I did find some nasty rust in the process but at least now I know where I have rust and why.

    Any suggestions would be lovely

    Thanks
    Jan
    1976 280Z
    HLS30288273

  21. #21
    Registered User Lazeum's Avatar
    Member ID
    CZCC-15411
    Join Date
    Nov 2007
    Location
    Paris, France (prev. Troy, Mi)
    Posts
    302

    Default

    I had a noise occurring only on bumps on my car after full restoration.
    Everything was tight as it was supposed to be. I made sure of it at every step of the process.

    It appeared shock (Bilstein unit) inside strut housing was loose. What happened was gland nut was tight against shock during assembly but it was most likely not well installed inside the nut. At the first bump/load, the strut moved back inside gland nut creating some loose condition.
    I had to take apart rear suspension & spring to find the issue. Since spring is putting pressure on your system you couldn't feel it otherwise. As soon as preload disappeared, issue became obvious. I just had to tighten the gland nut to bring back everything to normal. It was a 1 hr fix with the right tools (you need to disconnect brake lines to do so).

    Not sure it's your problem but it might be worth a check if you do not have stock suspension... (who does not after 40 yrs of service?)
    Last edited by Lazeum; 07-22-2013 at 04:54 AM.
    Matt - 72' 240z

  22. #22
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Well I found the source of the noise, oddly enough by putting something in the trunk. The rear sway bar mount on the passengers side is no longer attached to the car, as in it broke off. I haven't taken a good look at it as it was dark but it looks like it had prior rust on it and just broke off. I don't really know where to go from this point. I don't own nor do I know how to weld. I'm assuming this isn't exactly safe to drive with as it will just do more damage correct? The car doesn't handle any different but the noise(s) it makes are scaring me and I don't want to ruin it more then it is already ruined. Any suggestions would be wonderful. Can one run without said rear sway bar?

    Thanks
    Last edited by Pomorza; 07-26-2013 at 08:41 PM.
    1976 280Z
    HLS30288273

  23. #23
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    So I pulled the sway bar off to see the extent of the damage. The passenger's side mount literally sheared off the car, there's no rust, it literally just came off. Attached is the picture. I'm currently going to run without the sway bar in there rear until I figure out what to do with this.

    Click image for larger version. 

Name:	DSCN0006.jpg 
Views:	74 
Size:	126.8 KB 
ID:	64831

    Thanks guys
    Jan
    1976 280Z
    HLS30288273

  24. #24
    Z geek at large FastWoman's Avatar
    Member ID
    CZCC-19635
    Join Date
    Jul 2009
    Location
    Hampton Roads, VA
    Posts
    2,787

    Default

    I won't swear to it, but I think there are (local) spring shops that can make you a custom sway bar. At least there was a shop local to me where I lived long ago. They made me a coil spring.
    My last three sports cars while I still owned all three:

    2001 BMW Z3 Roadster 3.0i soft/hard top (sold)
    1966 Ford Mustang Coupe (sold)
    1978 Datsun 280Z (enjoying very much )

  25. #25
    Low Budget/High Value
    Member ID
    CZCC-20342
    Join Date
    Oct 2009
    Location
    Washington County, OR
    Posts
    3,629

    Default

    It's the mount, not the bar, if I read it right.

    If it was my car, I might just take the mount (off of the bar) and the car to a "muffler" shop and ask if they can weld it back on. The old marks are still on the car and exhaust-building pros are used to welding thin metal. Might be less than $50, I would guess. Clean up the mount and the spot on the car first and it will be even cheaper. Worst case, they'll just give some advice on why it won't work, and the right way to do it.
    1976 280Z, with some minor modifications

  26. #26
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Thank guys for the suggestions. I've talked to a few people I know and may end up buying the anti-roll bars sold by Beta Motorsports. If anyone has any reasons why not to do that, or any other suggestions let me know.

    Thanks
    Jan
    1976 280Z
    HLS30288273

  27. #27
    Registered User ZCurves's Avatar
    Member ID
    CZCC-7312
    Join Date
    Nov 2004
    Location
    Spring, Texas USA
    Age
    55
    Posts
    1,052

    Default

    I would do what Zed Head suggests. As for the Beta Motorsports anti-roll bars, I do not believe that you will realize a payback for the investment - besides you will need to have a place to mount them. IMHO - You will get more benefit from Urethane Bushings than a new roll bar setup.
    Andrew (ZCurves)
    1978 Coupe - HLS30-440105
    Spring, Texas USA

    pro deo et patria
    My Albumz

  28. #28
    Registered User LeonV's Avatar
    Member ID
    CZCC-19146
    Join Date
    Apr 2009
    Location
    Bay Area, CA
    Posts
    1,961

    Default

    Quote Originally Posted by ZCurves View Post
    I would do what Zed Head suggests. As for the Beta Motorsports anti-roll bars, I do not believe that you will realize a payback for the investment - besides you will need to have a place to mount them. IMHO - You will get more benefit from Urethane Bushings than a new roll bar setup.
    I don't think you understand, John sells ST ARBs which mount to the rear transverse link supports and not the frame.

    It all comes down to what you want. Do you WANT stiffer ARBs? If the answer is no, then go with the weld-it-back-up idea. Might as well do bushings and end-links at the same time...
    2/74 260Z

  29. #29
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Guys,

    Thanks for the suggestions. The bushings and end links are all new, I replaced them about a year ago with brand new poly bushings. As for wedling it back on, I've driven without it for about a week now and find that I actually enjoy it. Yes the suspension is a bit bouncier but its all good.

    Thanks
    Jan
    1976 280Z
    HLS30288273

  30. #30
    Registered User LeonV's Avatar
    Member ID
    CZCC-19146
    Join Date
    Apr 2009
    Location
    Bay Area, CA
    Posts
    1,961

    Default

    Quote Originally Posted by Pomorza View Post
    Guys,

    Thanks for the suggestions. The bushings and end links are all new, I replaced them about a year ago with brand new poly bushings. As for wedling it back on, I've driven without it for about a week now and find that I actually enjoy it. Yes the suspension is a bit bouncier but its all good.

    Thanks
    Jan
    Not sure what you mean by the suspension being "a bit bouncier" but removing the rear ARB should not be detrimental to around-town driving. It will only be noticeable when the car is driven harder, as an increase in steady-state understeer. The ARB does nothing if both wheels are in jounce/rebound.
    2/74 260Z

  31. #31
    Registered User
    Member ID
    CZCC-19999
    Join Date
    Sep 2009
    Location
    Tucson Az
    Posts
    696

    Default

    Leon

    In turns its a bit bouncier, as in a bit more rear end happy, understeer was what I was getting at. I drove it rather hard the night I pulled the bar off to see what the changes were.

    Thanks
    Jan
    1976 280Z
    HLS30288273

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. I have ....sip, sip ,sip noise
    By 72 OJ in forum Help Me !!
    Replies: 8
    Last Post: 02-27-2012, 03:06 PM
  2. Noise in rear.
    By 2.8.0.z.x in forum Engine and Drivetrain (S30)
    Replies: 4
    Last Post: 12-24-2007, 05:49 PM
  3. Fan noise
    By 240zGraham73 in forum Open S30 Z Discussions
    Replies: 3
    Last Post: 10-17-2007, 05:37 PM
  4. noise at take off ??
    By gator in forum Suspension and Steering (S30)
    Replies: 2
    Last Post: 11-26-2005, 03:02 PM
  5. Noise on Take off
    By Xargon321 in forum Suspension and Steering (S30)
    Replies: 2
    Last Post: 10-21-2003, 09:05 PM

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •