it couldnt be the crank pulley damper could it? i know land rovers have the problem every now and again, and i noticed the crank pulley is damped in a similar way on these..
I have actually fitted a new standard nissan crank damper pulley, I was lead to believe these are balanced individually so as long as the pulley is balanced and the rubber is not perished it should be fine to fit on my engine.
Thats something Ive had at the back of my mind for a while.
I thought the same, so have been looking into ross harmonic balancers but that said it really can't be my engine surely... With it out of gear the clutch, input shaft and flywheel (obviously) are all spinning when it's revved and I get nothing, that doesn't rule out revving/decelerating whilst loaded but it does prove that the rotating mass of the stuff attached to the crank isn't what's causing it alone... I am determined to get to te bottom of this, gonna prop the subframe up on blocks, chock the front wheels and run it through the gears, looking for odd movements and sources of noise. If I get nothing, then it's a load thing and I'll have to get it on a rolling road I know of and have another good look...
You tried knocking it out of gear whilst it's doing it? Without pressing the clutch.
Yes but that's the same deal as pressing the clutch anyway, it's removing all the load from the drivetrain and droppin the revs to idle simultaneously
Yeh, just wondered if it was relating to the clutch being depressed...
It's not noticeable in first, and hardly noticeable in fifth. 2/3/4 when off throttle coasting between 3-2k is where it happens. Like a vibrating resonance throughout the floorpan from back to front. Very hard to pinpoint unless I start being more creative lol.
yup, real hard to pinpoint!
Ive had it on a lift a few times and driven through all the gears, the prop assembly seemed to spin extremely smooth at any rpm or gear.
Although i couldn’t get it to reproduce the large vibrations it produces on the road, I could definitely detect some sort of vibration running though the transmission.
This bought me back to the clutch and flywheel setup again.
Shite Well hopefully I can find something but seeing as it sounds as though you're having the exact same problem then I won't hold too many hopes
It's crazy because an sr is an sr, the lightened fly and clutch is common as anything on them so what the hell is it.... So annoying. Sooner or later it will be my excuse to go RB or LS but I have such a good sr in mine is loathe to give up that easily
So pleased I've read this thread!
Just changed my gearbox, clutch and flywheel on my S14 at the weekend, did about 50 miles and I've now got this strange vibration/resonation that you describe, it's hard to pinpoint exactly where but feels like its underneath at the rear. I checked everything I touched underneath last night and everything is tight, I had it in the air and put it in gear and everything seemed to spin straight, it's hard to do a true examination though.
I've just removed the original box and flywheel and replaced with a known good condition gearbox and skimmed standard flywheel and XTD stage 4 paddle clutch (previously had a stage 3 paddle with no problems)
I disconnected the propshaft at the diff when I did the box so it went back in exactly how it came out. I've never ever had this problem before.
Kind of pleased that I hopefully know what the problem is now, as I was thinking about what I could swap over.
One thing that I would mention, something I wisely decided not to swap over were the dals which go between the box and engine to centre them. Once I'd finished the starter was grinding, in the end I managed to shift the starter over enough so it engaged the flywheel correctly. Is it possible the box itself is a mm out?
Did you put your dals back in?
It's the weekender this weekend so I'm not going to have a chance to do much about it but at least I know what I'm up against now, the car will get driven anyway as it doesn't seem an absolute major problem waiting to self destruct, such a shame it's happened though.
Be interested to see your views on this, I didn't expect to find someone with exactly the same symptoms. I'll report back if I find anything.
I have the same problem as you dean but have been told/read from a few reliable sources that it is just nvh coming from the fact i was running an eyedy hyper single and solid fly like you. It's even more noticeable if you're running uprated engine/gearbox/subframe bushes. The only solution i was given was to revert to dual mass and run a sprung s14 clutch plate. Apparently it causes no actual damage, it just sounds awful! Ps I had the work done on my s15 at the same place as you.
Another thought, do you run the stock diff? I can't seem to remember my car making the noise when i had a cusco 2 way in it...
Very interesting that you say that.. the clutch I just removed was a sprung plate and the stage 4 one i've just installed is non-sprung! I wondered what the difference was...
No actual damage.. in which case it doesn't really bother me I just don't like thinking somethings going to fly off!
THANKYOU, lol. I can go to the weekender non-paranoid!
Is this what your talking about, my old clutch on the right. To be honest thats the only thing i've changed, flywheel was skimmed so should be ok
Yeah, you're now running a full solid clutch setup so expect to hear a lot more nvh!!
Il add myself to this list.
I admire Hesky's determination but unfortunately he seems to have exhausted any solution already
In contrast, I have done fook all about it If it's any consolation, I have used and abused it since and nothing has changed, apart from main shaft bearing getting a lot noiser.
This is Heskys old thread, there is a video of the noise inside.
http://www.sxoc.com/vbb/showthread.p...smission-Noise
Im currently getting a custom 2 piece propshaft made up to replace the notchy ones its running at the mo.
I wanted to get them rebuilt, but Nissan annoyingly use staked u-joints so no prop shop will touch them.
Bloody expensive and very doubtful they will cure the issue as its rpm related, but I wanted to get the old ones replace anyway.
Must admit Ive been having rude thoughts about rb'ing it, but Ive spent loads on the SR lump and I have an awesome OSG 5-speed close ratio box Ive had freshly built up that I desperately want to try out with the skyline diff gears, but that’s a no go until I get to the bottom of this problem, just not comfortable risking it.
I'm determined its the clutch setup, so will be trying yet another when I get the new props.
There really is no solution, it appears that if you lose the dual mass you will have to accept more nvh... Its worse if like mine you have all polybushes etc, I sold the car the other day and the new owner understood the extra noise and was still very happy with the car. I currently have a perfectly good prop (the rear half is s15 and the front s14) left over from my build. It was painted and proffesionally balanced so if anyone is in need of one let me know, it fits s14 or s15 with a 5 speed box. I'm after 40 quid collected for it, it's known as perfectly good with a good bearing so it's worth it
My 14 doesn't have a dual mass flywheel and I don't get any noises like that. That sounds like something is rubbing on something rotating.. I assume it's not or you'd have found it! It is a strange noise, it might just be the floor pan resonating at certain rpm. Try sticking a big don of sound proofing stuff somewhere to change the resonant frequency? God knows!