Maserati Gransport vibration

[Lewis Gregory]

IIRC the only difference between the Quattroporte engine mount and 4200 transmission mount is the metal plate on top of the mount, which can be unscrewed and reused from the old one.

The GranTurismo transmission mount has the same mounting plate as the 4200 mount, but I think the rubber itself is taller overall.

I would like to confirmation about the gearbox mount, as if true there is a substantial saving there. The 4200/Gransport mount is about £500, wear as the quatrroporte mount is just over £100. It looks like the QP uses two mounts though, so not sure if it would be the same as the GS/4200?

 

[Twinspark]

I would like to confirmation about the gearbox mount, as if true there is a substantial saving there. The 4200/Gransport mount is about £500, wear as the quatrroporte mount is just over £100. It looks like the QP uses two mounts though, so not sure if it would be the same as the GS/4200?

What's confirmed is using the Quattroporte engine mount as the 4200 gearbox mount, you just have to unscrew the mounting plate from your old mount and put it on the new one.

 

[Lewis Gregory]

What's confirmed is using the Quattroporte engine mount as the 4200 gearbox mount, you just have to unscrew the mounting plate from your old mount and put it on the new one.

Yes, understood - but you mentioned the gearbox mount also - is this fact or a guess?

 

[Moz1000]

I assume you mean the propshaft, which runs inside the torque tube. The torque tube doesn't move or rotate.

**** of a test as well. Lots or work. Also, don't pneumatic drills go in and out, not round and round?

C

Yes the shaft inside the tube. Air-driven drill then. So the speed can be altered without touching the drill itself.
Ffs.

 

[Zep]

Yes, understood - but you mentioned the gearbox mount also - is this fact or a guess?

If I were you I would order them and measure up, you can always return and everyone here would be pleased to know if it is a success!

 

[TimR]

If I were you I would order them and measure up, you can always return and everyone here would be pleased to know if it is a success!

+1

I think I remember reading about this previously...

https://www.sportsmaserati.com/index.php?threads/gearbox-rear-bracket.29824/post-724277

 

[conaero]

The failed engine mounts are very easy to see. From underneath look at them and if the rubber centre domes downwards they are fine, if the are flat or dome upwards/inwards they have failed.

I assume Giallo noted this and hence the diagnosis.

Also, remove your aux belt and check the front crank pulley (which is a harmonic damper) has no play as it could have come loose and will give vibration issues.

This would have been removed to do the chains.

Left failed, right good:

 

[Lewis Gregory]

The failed engine mounts are very easy to see. From underneath look at them and if the rubber centre domes downwards they are fine, if the are flat or dome upwards/inwards they have failed.

I assume Giallo noted this and hence the diagnosis.

Also, remove your aux belt and check the front crank pulley has no play as it could have come loose and will give vibration issues.

I read the opposite, that they should be flat not domed down? If they are domed down then doesn’t that mean they are sagging? Flat or domed up would mean they haven’t collapsed as the weight of the engine is ok the middle rubber section? Would be good to know for sure!

With regards to the pulley - good point, Giallo did the timing chains so this has been off recently. I can’t imagine the car had the issues before it went in for all the work, unless it was the reason for the work as the previous owner was a perfectionist who maintained the car regardless of cost. The service record is crazy! To me it’s a strange coincidence that it’s vibrating after the clutch, subframe and timing chains were changed as all could have effect on vibration.

 

[Lewis Gregory]

Thanks for everyone’s help so far!

 

[lifes2short]

The car also wore though the edge of the new michellins fitted by Giallo in about 4000 miles, the main tyre is perfect, about 6mm of tread but the inner edge has webbing showing - is this normal?

6mm down to cord on other side, that's shocking, bearing in mind 8mm is new depth, not familiar with your motor but vibration of that type can be from problem propshaft or as as mentioned already worn prop bearings

 

[conaero]

I read the opposite, that they should be flat not domed down? If they are domed down then doesn’t that mean they are sagging? Flat or domed up would mean they haven’t collapsed as the weight of the engine is ok the middle rubber section? Would be good to know for sure!

With regards to the pulley - good point, Giallo did the timing chains so this has been off recently. I can’t imagine the car had the issues before it went in for all the work, unless it was the reason for the work as the previous owner was a perfectionist who maintained the car regardless of cost. The service record is crazy! To me it’s a strange coincidence that it’s vibrating after the clutch, subframe and timing chains were changed as all could have effect on vibration.

Under load they should dome out.

And I’m not saying Giallo left your crank pulley loose, do the mounts as they said first then if you still have issues or want to check it, it’s worth doing.

It’s a 36mm socket and something like 350NM from memory so very tight. It’s a two man job and on a ramp with the fan pack out to take it on and off.

You can however, take the aux belt off and check it doesn’t wobble on the crank. You can also simply run the engine and watch it from the top. If it’s loose or failed it will be blurry. Also you will feel the vibration stationary, revving the car. It will be most noticeable through the steering wheel and floor pan.

 

[TimR]

It’s a 36mm socket and something like 350NM from memory so very tight. It’s a two man job and on a ramp with the fan pack out to take it on and off.

I know what you're saying - and they are fixed at over 400Nm with a strong, high temp loctite, according to the manual.
Not to say the pulley hasn't failed but over 3500 miles with a dampner pulley thats lose, doesnt that seem unlikely without quickly escalating issues ?
I recently did much of this work to get at an oil/water pump o-ring that was leaking coolant. I have recently noticed a slight vibration in the cabin at +2500 rpms ish...and can see vibration at the pulley at idle ! Are you saying the engine should have no visibly discernible vibration @ 1000rpms...

 

[Lewis Gregory]

Under load they should dome out.

And I’m not saying Giallo left your crank pulley loose, do the mounts as they said first then if you still have issues or want to check it, it’s worth doing.

It’s a 36mm socket and something like 350NM from memory so very tight. It’s a two man job and on a ramp with the fan pack out to take it on and off.

You can however, take the aux belt off and check it doesn’t wobble on the crank. You can also simply run the engine and watch it from the top. If it’s loose or failed it will be blurry. Also you will feel the vibration stationary, revving the car. It will be most noticeable through the steering wheel and floor pan.

Mine are domed down, so from that you think the engine mounts are fine?

 

[Lewis Gregory]

Mine are domed down, so from that you think the engine mounts are fine?

This is what I read before, and mine looks like the heavily domed one.

 

[Lewis Gregory]

I’ve now got my car up in the air, and jacked the engine up to find a lot of movement in the mounts. Dues anyone know if the mounts can be removed by jacking the engine up?

 

[RJ237]

I have read a couple of threads on the ML forum that indicated the sub frame had to be dropped a little. Hopefully someone on this forum will respond as there are many experienced members.

 

[Mr S]

I seem to remember you can remove the engine mounts by jacking the engine up slightly after unbolting the mounts.

 

[Lewis Gregory]

I seem to remember you can remove the engine mounts by jacking the engine up slightly after unbolting the mounts.

I managed to get one side done last night, had to unbolt the exhaust from the manifold to get clearance. The hardest part was the top bolt on the mount as it’s hard to reach and takes a lot of force to crack. There is not a lot of difference between the old and new engine mounts, I’m not holding much hope out for this causing a resolution.

 

[Lewis Gregory]

The failed engine mounts are very easy to see. From underneath look at them and if the rubber centre domes downwards they are fine, if the are flat or dome upwards/inwards they have failed.

I assume Giallo noted this and hence the diagnosis.

Also, remove your aux belt and check the front crank pulley (which is a harmonic damper) has no play as it could have come loose and will give vibration issues.

This would have been removed to do the chains.

Left failed, right good:

View attachment 76675

Here is my old verses new photo.

 

[Mr S]

Personally id say the new ones look alot better, so fingers crossed. When i changed my manifolds over to the Euro ones, we had to lift the engine, thats how i knew. Where did you get the mounts from?