Vibration ??Engine mounts??

[Tom.H]

Hi everyone

I recently brought a rear engine land rover. The previous owner of the vehicle changed the standard engine mounts with captive ones.

These captive engine mounts were built around a land rover rear radius arm and from what I know use the standard bushes.

The problem I have is that the car vibrates terribly. At first I thought it might have something to do with the frequency of the chassis and engine being the same but the issue occurs at any rpm.

I feel I have two options. The first being to look for an extremely soft rear radius arm bushes, if they even exist (does anyone know of any)?

The other being to create a new engine mount or even try and re create the stand land rover one. After looking at the amount of actually rubber in a radius arm and comparing it to what’s normally used its clear to see why a vibrating issue might occur.

I just wondered if anyone could help me out.

Here are a few pictures of one of the mounts (the other one being very similar)

Many thanks

Tom

[steve_d]

From the last photo it looks to me as if the bush is shot and likely has metal to metal contact hence your vibration.

Replacement with a standard bush may be all you require.

Steve

[Tom.H]

Ok

Thanks for your help

As the mounts are quite easy to take off, my plans are to replace the bushes.

If this does not prevent the vibration then I plan to look into recreating the standard mounts

Tom

[Phil Hancock]

Blue or orange polies might be an alternative.

[rusty_wingnut]

or do a search, i made some based on a narrow front radius arm bush and these have been very succesful, they have been restraining a 4.2 V8 for over a year now.

[Aragorn]

I recon the front radius arm bushes would be better. The rear ones that have been used there have a very small amount of rubber, and this will cause a lot of vibration transmission.

[Tom.H]

Ok

I’ve replaced the bushes to Braitpart Poly ones. There was a defiant improvement but it’s become apparent to me that the issue might not just be a result of the engine mounts.

Outside the vehicle it doesn’t seem to vibrate any more than a normal defender but when inside the cab its clear that the drumming/vibrating affected is exaggerated.

I am guessing this is basically due to the cab having no sound proofing at all and there being just a thin sheet of ally between the engine and me

Of course it is quite an ask attempting to make a vehicle which was first designed for safari events comfortable but as I am planning on do challenge event the issue is becoming more and more apparent

I just wondered if anyone had any experience of sound proofing their vehicle and whether they could tell me what materials they used.

Tom

[Lars L]

I think the problem is that these bushes are far too small and not containing enough material to absorb vibration from an engine. I also had quite some vibrations and resonance noise in my ex-MoD. Didn't get any better after installing a 200Tdi. I then changed the standard rubber bushes to similar ones from a company making all sorts of anti vibration thingies for industrial use and that made a world of difference.

[rusty_wingnut]

check the gearbox isn't slapping the seatbox/tunnel, check the engine isn't slapping the bulkhead

[MECCANO]

Ok

I’ve replaced the bushes to Braitpart Poly ones. There was a defiant improvement but it’s become apparent to me that the issue might not just be a result of the engine mounts.

Outside the vehicle it doesn’t seem to vibrate any more than a normal defender but when inside the cab its clear that the drumming/vibrating affected is exaggerated.

I am guessing this is basically due to the cab having no sound proofing at all and there being just a thin sheet of ally between the engine and me

Of course it is quite an ask attempting to make a vehicle which was first designed for safari events comfortable but as I am planning on do challenge event the issue is becoming more and more apparent

I just wondered if anyone had any experience of sound proofing their vehicle and whether they could tell me what materials they used.

Tom

I exprienced the same effect you discribed, but in a citreon saxo. I upgraded the lower engine/ gearbox mount on my fwd car as it was prone to failure every 10k, with that almost idetical to the bush you have shown. From the outside you wouldn't notice the added vibration/ noise. Once inside it seemed to resonate around the interior. The vibration was enough for the steering wheel to become a blur at idle, when started on a cold day.

[Aragorn]

Ditto. I installed some polyurethane engine mounts in an old Nova i had, and the vibrations it put thru the shell were way OTT.

You need more rubber. Those bushes just arent big enough to absorb the vibrations from an engine as has been said already.

[Tom.H]

Thanks for your help again

It seems that a few of you have had a similar experience to me. I am still convinced that the issue is due to the body having no sound proofing.

I am able to sit on the roll cage above the cab, next to the engine and on the front wing bars there basically no issue with vibrating or sound, at all.

When I open the door and go inside the cab the noise and vibrating affect is pretty apparent and as all ready said seems to be exaggerated.

I feel this is due to the thin ally material flexing and almost acting like a drum. I am hoping that the sound material I use (When I find some) will prevent the body from flexing as well as covering up the sound.

As you can see from the pictures there basically one sheet between the engine and me and just a few from the gearbox/transfer box and me (being that theres no longer a battery box)

Thanks

Tom

[ChrisM_110]

I have used Screwfix flashing tape with excellent results. Bitumen adhesive with an ally top layer. Heat up a panel with an air gun & slap it on. Used under floor panels, hardtop and sides and seatbox. Great stuff and sticks like burberry sticks to chavs.

[Bush65]

Thanks for your help again

It seems that a few of you have had a similar experience to me. I am still convinced that the issue is due to the body having no sound proofing.

I am able to sit on the roll cage above the cab, next to the engine and on the front wing bars there basically no issue with vibrating or sound, at all.

When I open the door and go inside the cab the noise and vibrating affect is pretty apparent and as all ready said seems to be exaggerated.

I feel this is due to the thin ally material flexing and almost acting like a drum. I am hoping that the sound material I use (When I find some) will prevent the body from flexing as well as covering up the sound.

As you can see from the pictures there basically one sheet between the engine and me and just a few from the gearbox/transfer box and me (being that theres no longer a battery box)

Thanks

Tom

Those large thin flat panels will vibrate and transfer noise.

You need at minimum, a dampener material that adheres to the panels. Then if you want sound proofing a noise absorbent material on top of that.

Two links you may find useful

Sound Deadener Showdown

Noise Killer

[Lars L]

I spent heavily taxed Swedish crowns on a bucket of NoiseKiller Liquid some years ago. Well wasted IMHO, doesn't make any difference to write home about... The other stuff on their site makes a lot more sense, weight to stop vibration and foam to act as a barrier for airborn noise is what's needed.