herbiemercman Posted December 15, 2015 Share Posted December 15, 2015 Hi Guys, Has anyone had a situation where the vibration from the engine is getting onto the body of the car, the most noticeable bit is the clutch pedal and foot brake pedal are a bit like a high frequency foot massage, sort of tingling. The bulkhead seems to be where the main cross feed vibration from the engine is coming from. This condition is post my recent NA/T conversion, i did not notice it as much as i am doing currently as at the begining i was fighting a stage 4 clutch which was shuddering the car to bits, the past few weeks i am running a stage 2 clutch with almost stock smoothness, the clutch was changed by my local garage and it was post this that i started to notice the vibration problems. I cannot see what could have caused this as just dropping the gearbox etc is straight forward, is there any points where the gearbox etc can foul the bodywork? Could the engine mountings be getting tired or have been damaged with the juddering of the stage 4 clutch? I have eliminated all the obvious bits that touch the bodywork like baffles, boost pipes, waste gate dump pipe, down pipe etc. Any help will be much appreciated. Herbie. Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted December 15, 2015 Share Posted December 15, 2015 What about your engine/gearbox mounts? Quote Link to comment Share on other sites More sharing options...
Scooter Posted December 15, 2015 Share Posted December 15, 2015 Facelift engine mounts cause this all the time but pre facelift ones are usually fine. From underneath and through the wheel arch holes you can see the bottom of the engine mounts and there is a little triangle piece that sits on the subframe and there should be a few mm gap between that and the main body of the engine mount? If you are very careful you can take some weight (obviously don't go lifting the car) off the mounts by jacking up on the sump and see if the gap opens significantly? Also is there any flexi section in the exhaust at all? Quote Link to comment Share on other sites More sharing options...
Style Posted December 15, 2015 Share Posted December 15, 2015 My oil catch can was installed in a funny place and makes a bad rattling noise so I've put some rubber around the corner that catches the shell of the car for the time being. I need to relocate some stuff before I can mount it in it's originally designed slot. It may just be a piece of hardware from your conversion that is catching something dude. The clearance between my turbo housing and the suspension strut is millimeters. I'm convinced it'll touch when cranking the car so keeping an eye on the paint. My boost solenoid also makes a racket as it's installed right in front of the driver in the engine bay. Quote Link to comment Share on other sites More sharing options...
Shane Posted December 15, 2015 Share Posted December 15, 2015 Many moons ago I played with a supercharger on the first mkiv I owned http://www.mkivsupra.net/vbb/showthread.php?123865-Supercharger-latest-pics&highlight=shane+eaton and I had similar vibration issues, mine was down to the throttle cable. Has yours been dressed differently to stock or is it coming into contact with something? Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted December 15, 2015 Author Share Posted December 15, 2015 Thanks for comments guys, Scooter, Style, Shane, and Swampy, My throttle cable passes through an ali heat baffle which sits between the very hot down pipe so this is a place to look. I will observe the engine mounts as suggested, these and the gearbox mounts are the key suspect IMHO. The exhaust is ok well clear of any bodywork. The boost pipes are touching the holes in the chassis and also fouling the front fender, need to look at this? It's just that the vibration is so powerful that i must be looking for an engine mounting or gearbox mounting, the other items of concern would be noisy, but not producing such a solid deep vibration, to make the foot pedals vibrate, when you get up to speed in top gear it is fine, starting off in first and second gear seems to bring it on the most? Herbie. Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted December 26, 2015 Author Share Posted December 26, 2015 Hi Guys, The engine mounts are ok, not sure as yet on the gearbox mounts, but i sorted the boost pipe fouling and put some high density foam pads between all contact points, this has reduced the worst of the vibration noise, i still have the vibration on the clutch pedal, its not noisy just does not feel right. I will live with this for a while and keep investigating what could cause this, the clutch operates fine just the bit of a judder, but nothing like the mega juddering with the stage 4 competition clutch. Herbie. Quote Link to comment Share on other sites More sharing options...
Abz Posted December 26, 2015 Share Posted December 26, 2015 Not sure if this might be an option for the NA5 boxes but does this have a dual mass flywheel? Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted December 27, 2015 Author Share Posted December 27, 2015 Hi Abz, I had never heard of a DMF (dual mass flywheel) before, but this seems a great tool, my car never had one pre the NA/T conversion? are you saying that the extra power i now enjoy can cause vibration due to the stage 2 clutch i have? Herbie. https://en.wikipedia.org/wiki/Dual_mass_flywheel Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 29, 2015 Share Posted December 29, 2015 (edited) Vibration through the pedal can either be there all the time, or only when you depress it enough for the release bearing to contact the diaphragm fingers. If the clutch has no free play a push type clutch like yours will have the bearing permanently in touch with the fingers, and the vibration may then be there without depressing the pedal much at all. Why would the pedal vibrate? Bent diaphragm fingers from a dodgy install, allowing the gearbox input shaft to bend the fingers as the gearbox is swung wildly about by savages. Or maybe a from the get go dodgy clutch cover. If the pedal vibrates against your foot it's being transmitted up the hydraulic fluid and must originate at the release bearing, which itself is being thrusted fore and aft and not merely being rotated. I suppose a badly machined or otherwise out of kilter flywheel could do it, or even a bent crank, but that would be extreme. VERY few cerametallic clutches will never judder, that's why stock clutches use organic linings *and* either a dampened flywheel or a dampened (sprung) driven plate. Google sprung and unsprung driven plates. They don't take kindly to being slipped, so what happens is they judder, so people slip them more to try and get through that phase. that adds more heat that they are poor at dissipating, so they warp, and the judder worsens or they won't then fully release. The vicious circle then tightens. Happy New Year, are you flooded? Edited December 29, 2015 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted December 30, 2015 Author Share Posted December 30, 2015 Hi Chris, Clutch works ok is it normal to have a slight vibration as I described? Herbie. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 30, 2015 Share Posted December 30, 2015 Through the pedal? No, something's running out of true. But it may give no other issues with any luck. Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted December 30, 2015 Author Share Posted December 30, 2015 Thanks Chris, can you move to Preston. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 30, 2015 Share Posted December 30, 2015 Sorry, I don't have a boat, and my Bangladeshi is extremely limited.... Quote Link to comment Share on other sites More sharing options...
herbiemercman Posted January 1, 2016 Author Share Posted January 1, 2016 There are a few Enlish people still here, some suffering from whiplash scams.lol. Quote Link to comment Share on other sites More sharing options...
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