Gearbox (and engine) mounts

[stuartturbo]

On the movement front what about a brace as used on many other cars?

[Kieran]

Interesting. There is a tiny bit of give in these flexane ones, but when I say tiny I mean me doing push ups on it and the bushing moving slightly!

I'll refit the rear one first as that's the most awkward to get at and then the transmission mount.. I can get lever bars and such in easier for that one if I need to....

[Kieran]

On the movement front what about a brace as used on many other cars?

A torque damper you mean? Like a little shock absorber? Never seen one for the galant/legnum, though one exists for the Evo... Can't be that difficult to adapt?

[Eurospec]

Pit road M sell one for the GTO which you might be able to adapt.

The issue is that the mounts are obviously the opposite way round.
As Kieran said, the EVO one would be a better bet, as it will be handed correctly.

Normally the damper goes between the side engine mount and the top of the suspension strut. You would think in that position it would have to resist a huge moment- which it does- but the pitroad one seems to work.

When thinking about mounts you have the choise of:-

New OEM
Filling OEM with poly etc to stiffen them up (does work)
New Polly bush inserts done as Richard suggested
Solid.

Solid mounts are the ultimate for the drag guys, and getting every last bit out of the launch, but, there is no cushioning at all. I have seen both fto and GTO with standard gerabox mounts litterally snap the casing when something has impacted hard. With a solid metal mount this will become even more likely.

Check this nastyness:-

http://img.photobucket.com/albums/v3...h/gearBork.jpg


Solid mounts also pass every vibration into the car so the car feels very rumbly. I recon with solid mounts you wouldnt have to hit something that hard to punch a hole in the gearbox. Imagine smacking the mount point with a 5 lb hammer. Now imagine smacking it with the weight of the gearbox. You wouldnt need to smack that hard to break it i wouldnt have thought.

Poly mounts are a good compromise, but again you feel a lot more vibration. They are a bugger to fit.

As mentioned earlier in the thread, the std mount is rubber within a metal colar which is a press fit into the mount itself. To fit polly, you have to get all this out. I have tried heaps of ways, notably, pushing the old bush out with a press, which just results in the rubber distorting a ridiculous amount, but no movement. I've tried cleaning the rubber out with a knife/scrapers to get a clean surface (on the metal collar) to get the new bush in. This takes hours and never works! Finally i settled on getting poly bushes which are slightly oversize for the ID of the mount itself (not the collar).

Get the mount off the car and burn the rubber bush out with the oxy. (lots of acrid smoke) Using the air saw or hack saw to cut into the metal collar to split it. Finally then push the metal colar out, clean up the inside of the mount, lube it with ATF, then press the new polly bush into it.

Strengthening existing bushes works well too, though its not something we do, i know a lot of people have done it, and it does work, and is surprisingly permanant!

Cheers,

Ben.

[Kieran]

Weather permitting, I should be able to fit my flexaned mounts tomorrow. they're all new - all the old bushing rubber was burned/wire brushed out.

[BraindG]

Having read through post #28, I have a question regarding failed/failing engine mounts.

What sort of issues would you experience if your car had failed/failing engine mounts? Vibrations? any odd behaviour from the car?

Ta.

[Axeboy]

Does failed mounts not cause a 'shunt' under acceleration or heaving braking?


Accelerate hard and lift off, you will notice its weight moving this way.

[Kieran]

Well, you will need to visually inspect them. Look for tears, cracks and 'perished rubber' stress marks around the edge of the bushing rubber where it connects to the eyelet and the mounting body.

Look also to see if the eyelet is centred. If it's moved out of position, it may be on the way.

Look for bulging engine mount rubbers...the rubber should be flush to the casing - if it's bulging out either side, it's being compressed too much.

Look under the car - the gearbox should be clear of the crossmember that runs front to back under the engine. If it's touching, then something's up.

Having driven two VR-4s with known 'good' mounts, my car feels more 'mechanical' in comparrison. You hear a lot more drivetrain noise, and there's some vibration at idle.

[Kieran]

Does failed mounts not cause a 'shunt' under acceleration or. heaving braking?


Accelerate hard and lift off, you will notice its weight moving this way.

Yes - that's very true, it does. I've had that.

[BraindG]

I was wondering whether or not it might have something to do with my judder under acceleration. (hard acceration its ok(ish) - normal its quite bad)

[Wodjno]

I think mine have been Ducked for a Long Long time..
I get shunt everytime i touch the accelerator pedal and when i come off it.. Plus under hard acceleration i get Humungus amounts of vibration... Always have since i fitted a boost controller..

[stuey]

Mine were knackered when i bought the car, top one in pic below, all 4 changed for new mitsi ones asap. didn't notice massive change, definately less vibration in general and odd noises gone...

[Kieran]

Mine were knackered when i bought the car, top one in pic below, all 4 changed for new mitsi ones asap. didn't notice massive change, definately less vibration in general and odd noises gone...

Blimey - yes, people in Club VR-4Land, if your engine mount looks anything like that... It's well and truly goosed!

[Kieran]

Right! Well, the repaired mounts are back in and bolted up - with minimal frasser rassering too!

Now to have a cuppa and then I'll tackle the driveshaft boot and then I'll be able to drive her around and see what's what!

[Kieran]

So! were my Flexane antics in vain?

Definetly Not.

Okay, here's what I've noticed, though bear in mind my original mounts were trashed - so if yours are good, you may want to think carefully about this mod. In fact I would say that unless you have a manual car and you're chasing 60ft times, or you've got shagged engine mounts... You probably don't need to faff about with all of this. For reference, my rearmost mounting and the gearbox mounting are now flexane ones, and I used Flexane '60'. The others (the little one on the crossmember and the one attached to the engine on the driver's side) are OEM. The little crossmember mounting is worn, but not torn. It will soon need replacing though. The drivers side mounting appears to be in good, servicable condition, having been replaced already.

Anyway - My views...

At idle and when starting, the cabin is more refined. The engine noise is more muted and there's less vibration. You used to feel the engine 'kick' as it fired - not any more.

When put into Drive (that's FORWARD 1,2,3,4,5 for all you spakkerbox owners ) and left at idle there is slightly more vibration in the cabin. It seems that anything below 800rpm and the flexane transmits the noise. I imagine this would be more pronounced with a harder grade of flexane.

There's no more transmission 'shunt' when putting the car into gear. It just engages.

There' s much less gearbox noise when underway. Before, you could hear the gearbox as it engaged gears and such - lots of whining and bearing noise - not surprising as the gearbox was resting on the crossmember!

As for a 'crisper' drive... I can't honestly say I notice any difference in that respect - I suspect that's more of a manual thing though.

So yes, all in all - Mission successful!

[psbarham]

cool , i'll order some then , glen do ya wanna do yours at the same time ?

[BraindG]

interesting Kieran, thank you.

I was consideing doing this aswell, might just get the stuff ordered and do it now.

[Axeboy]

How long did it take to remove the old mounts K?

[Kieran]

How long did it take to remove the old mounts K?

Well, I started (that is, wandered to the garage with a steaming cuppa and started getting all the tools and such out) at 10AM and they were out and I was done and packed away by about 3pm. I would have been a lot quicker if it wasn't for the 3rd bolt on the rear engine mount.. It's underneat the mounting bush, so you can't see it from above, and from beneath it's obscured by the power steering rack. There's just enough room to get a flexi-head ratchet and a long reach 14mm socket onto it. Fortunately, it's so tucked away it doesn't get blasted by crap, so the threads hadn't rusted.

Rough guide (very rough!)

Gearbox mount:

Battery out.
Battery tray out.
Lower crossmember and front engine roll stopper out. Support the gearbox with a jack or stand.
Then:
Crack bushing bolt (17mm)
Crack the three bolts holding the mount to the gearbox (long reach 17mm)
Support the gearbox/engine joint lip with suitable jack and block of wood. Pump the jack up to take the weight off the bushing. It'll take a fair old bit.
Remove 3 mounting nuts.
Remove bushing bolt.. You may need to manipulate the jack a tad to help it withdraw - if you've ever removed the front shock fork - lower arm bolt you'll know what to do. A tap from a rawhide hammer and a suitable drift will help.
Now... The mount is unbolted, but removal is tricky. I used the workshop manual method.... Seems rather hairy, but there we go.... What you do is lower the jack, causing the gearbox to drop down. It'll drop several inches. Eventually you'll be able to waggle the mounting past the studs and out. Another way would be to get a set of stud extractors and take the mounting studs out the gearbox - this would save a lot of faffing with the jack.

Rear Mount:

Assuming you've already remvoed the gearbox mount. If not, get the crossmember out the way and support the gearbox

Airbox & MAF out.
Turbo inlet 'Y' pipe (behind MAF) and rear turbo flexi pipe out (the clips on these have 10mm nuts on them, but they can be very awkward to get at!
Evaportation canister out (a simple clip, unless like mine some mong's been at work and bolted the clip upside down at some point -making it impossible to refit!)
This will give you limited, but enough access. Now... long extension bar and 14mm socket on the back two bolts on the top of the mount. It *will* fit, the pipes that look like they're going to get in the way will move backwards a bit (into the padded heat sheilding) and give you JUST enough room to get the socket on the nut.
The bushing nut & bolt can be tight. However, if you put an extension bar on the nut, you will be able to get a breaker bar on the end of that and have enough 'swing' to operate it.
Then tackle the nut underneath. Seeing as you'll be quite a way underneath the car, make sure the gearbox is securely supported. I used an axle stand. On the refit I also used my engine hoist as a failsafe too.

That's only a very basic guide off the top of my head. The biggest headache is the rear mount, because of the limited space.

[Axeboy]

Nice one

My mounts *seem* to be fine, but its something I might add to the 'todo' list..

Cheers K