Engine vibration

Engines, Transmissions & Final Drive questions and answers

Moderators: timk, Stu, zombie, Andrew, The American, Lokiel, -alex, miata, StanTheMan, greenMachine, ManiacLachy, Daffy

Mechdude
Learner Driver
Posts: 2
Joined: Thu Jan 09, 2020 5:31 pm
Vehicle: NA8

Engine vibration

Postby Mechdude » Sat Jul 02, 2022 11:35 am

Hey all, I have an NA6 long nose with 250k+km that I weekend drive.
Just recently I have noticed some harsh vibrations coming through the gear lever and dash. (Gear knob is rattling off)
Seems to be engine speed dependant.
The first buzz is around 2.5 -3, and again from 4-4.5

Engine and ignition seems to be running fine otherwise.

Likely causes?
Harmonic balancer, engine mounts?
Thoughts

Cheers
Howard


Sent from my iPhone using Tapatalk

User avatar
bruce
Speed Racer
Posts: 7706
Joined: Fri Apr 25, 2003 11:00 am
Vehicle: NA8 - Turbo
Location: Victoria
Contact:

Re: Engine vibration

Postby bruce » Sat Jul 02, 2022 12:23 pm

Could try parking the car, lifting the bonnet, giving the engine a good rev and see whatsa shaking under the bonnet.

User avatar
ManiacLachy
Forum Guru
Posts: 3266
Joined: Mon Jan 13, 2014 2:35 pm
Vehicle: NB SE
Location: Brisbane

Re: Engine vibration

Postby ManiacLachy » Sat Jul 02, 2022 1:34 pm

Both motor mounts and the harmonic balancer are likely to be getting on if still original. They're both made with rubber that degrades.

You could give the engine a shove side to side to see if there's play. Also the harmonic balancer by hand, but when it degrades slipped timing is usually the issue.

93_Clubman
Speed Racer
Posts: 11852
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: Engine vibration

Postby 93_Clubman » Sun Jul 03, 2022 12:39 am

Mechdude wrote:have an NA6 long nose
noticed some harsh vibrations coming through the gear lever and dash. (Gear knob is rattling off)
first buzz is around 2.5 -3, and again from 4-4.5

Exhaust manifold heat sheild & the other exhaust heat sheilds are all prone to buzzing & rattling during certain rev ranges when their mounts or tabs break, but not usually to the extent of rattling the gear knob off.
There's also a dash mounting point under the pside of the dash that eventually gives way that causes vibration.
Whilst rare, the long nose 1.6 & 1.8 have been know to suffer from much the same issue as the short nose 1.6.


Return to “MX5 Engines, Transmission & Final Drive”

Who is online

Users browsing this forum: No registered users and 23 guests