"Drive plate" in a diesel. What is it, what does it do and how much w

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\"Drive plate\" in a diesel. What is it, what does it do and how much w

..... and also why has it likely failed (if it has). Volvo D1-30 suspected faulty "drive plate" failure tbc tomorrow, causing excessive vibration when idleing. Any ideas anyone ? Out of warranty by the way.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

a drive plate is the plate that fits on to a flywheel and the gearbox input spline goes into the centre of it, some of them have springs and some have a plastic or rubber centre to take act as a damper for when you put the gearbox in to drive
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

It is a cushioned plate attached to the flywheel with a splined hub that takes the input shaft from the gearbox. Its purpose is to cushion the drive from the uneven pulses of the engine. Failure could be either the springs that provide the cushion - this would cause vibration, or wear on the splines. This has been a problem in the past with the old 2002/3 series but not heard of it recently on newer models.

Hope this helps.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

you get something called torsional vibration caused by the engine running at low revs in gear, this can cause the drive plate to wear and or the spline on the gearbox to wear! usually just the drive plate, simple case of replacement of driveplate, in most cases!
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

The drive plate is the interface between the fly wheel and the input stub shaft on the gear box and normally has a female spline in the centre and this may have fretted away and failed.

It is good engineering practice to have some sort of dampening in the assembly to absorb the torsional oscilations of the engine when the flyheel is the other end of the crankshaft however it seems Volvo had a few new brooms who went to a different school and on the 2001/2/3 range the new brooms thought they would rewrite history and leave out the torsional damping. We all know the result!!!! I wasn't aware they had goofed on other engines!

You may need a new drive plate and a gearbox input shaft if it is a similar layout to the 2000 series.

Volvo are very good at avoiding warranty claims as seen by their responce to the 2000 problems and if you have a 4X4 estate car then you will know the meaning of two fingers if you replace either two front or two rear tyres and suffer gearbox failure. Kwik fit know about this one so they will try to convince you to buy four tyres at a time!

The cost of Volvo parts on the 2000 series was about £800 for Volvo parts though alternates are available however depending on the boat there could be a few hours or more labour charges.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

Heck this forum is brilliant !!!. Thanks chaps. Can anyone explain why it would cause excessive vibration whilst the engine is in neutral, yet the engine runs under load very well/quietly, and the engagement neutral/ahead/to stern seems to wrok fine ?.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

"Can anyone explain why it would cause excessive vibration whilst the engine is in neutral, yet the engine runs under load very well/quietly, and the engagement neutral/ahead/to stern seems to wrok fine ?."

Are you sure it's not just the idle revs set too low?
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

To be honest I am not convinced your problem is the drive plate however I could be proved wrong. WHen a drive plate fails there is not usually an increase in vibration as all the bits are held in place however you do lose drive.

I would be concerned about other things from what you are saying and the more likely cause of poor idling as you describe is a duff injector which picks up on load...

We had a Sea line here with volvos that had both engines shaking to pieces on idle . It had come here after a life on a river. The owner was quoted trillions of squids for new props and out drives...

Took us ten minutes out in the driver to determine that both engines each had at least 3 duff injectors. The next time I saw the owner he had a wall to wall smile and broke a cardinal rule by inviting a raggie on board for a drink !

What you can try is this....get a roll of kitchen tissue and a spanner that fits the injector HP connection.

With the engine on idle and whilst catching the drips holding the tissue around the injector connection slacken of the connections one at a time and see if the engine note fails to change then retighten. The revs should drop and vibration change as each one is slackened. If you find no change when one is slackened then that injector needs checking.

If you do have a duff injector the engine may well stall when you slack off one of the good ones. You are looking for the one(s) where there is no change in vibration/speed when slacked IE the lazy one.

Not much fuel will actually leak and you just need to slacken off and immediately retighten one by one.

Although this is safe with engines fitted with water cooled exhausts I would use extreme care doing this on engines fitted with dry exhausts and under load.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

Is the D1 30 in your Centaur? If so it is way overpowered. A 20 would be more than enough.

However, vibration in neutral is not likely to be the drive plate, but stemming from too low a tick over speed. I suspect the tickover has been set low to reduce the power at maneouvering speeds - one of the difficulties experienced when too big an engine is fitted. Ignore that bit if it is not in a Centaur, but the low tickover is worth investigating. Incidentally I have the previous model Volvo (2030) in my Bavaria 37 which is twice the size and dispalcement of a Centaur and it is more than adequate.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

[ QUOTE ]
...Can anyone explain why it would cause excessive vibration whilst the engine is in neutral, yet the engine runs under load very well/quietly,....

[/ QUOTE ]

No.

Seems very unlikely. Who has diagnosed this?

Engine mounts OK, tight, and evenly adjusted?
No pipework, etc. rattling against a bulkhead?

Proceed with caution!

Andy
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

I had a drive plate go on a 3 cylinder Vetus driving a narrowboat. OK in neutral but big clanging noise in forward. Still drivable with lots of noise & vibration.

IanC
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

[ QUOTE ]
What you can try is this....get a roll of kitchen tissue and a spanner that fits the injector HP connection.

With the engine on idle and whilst catching the drips holding the tissue around the injector connection slacken of the connections one at a time and see if the engine note fails to change then retighten. The revs should drop and vibration change as each one is slackened. If you find no change when one is slackened then that injector needs checking.


[/ QUOTE ]

We did exactly this today, and there was a definite change in note when each injector was slackened. Bit of a mystery this one, will keep you informed ......
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how much w

When you say vibration do you mean that when idling the engine shakes around a bit on its mounts quietly...or does it sound like its vibrating and makes lots of rattly noises?
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

[ QUOTE ]
"Can anyone explain why it would cause excessive vibration whilst the engine is in neutral, yet the engine runs under load very well/quietly, and the engagement neutral/ahead/to stern seems to wrok fine ?."

Are you sure it's not just the idle revs set too low?

[/ QUOTE ]

Idle speed is fine and the viration goes away at higher revs.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

[ QUOTE ]
To be honest I am not convinced your problem is the drive plate however I could be proved wrong. WHen a drive plate fails there is not usually an increase in vibration as all the bits are held in place however you do lose drive.

[/ QUOTE ]
The engine/gearbx drivs ahead and astern wth no problem and the shaking/vibration stops under load.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

[ QUOTE ]
Is the D1 30 in your Centaur? If so it is way overpowered. A 20 would be more than enough.

However, vibration in neutral is not likely to be the drive plate, but stemming from too low a tick over speed. I suspect the tickover has been set low to reduce the power at maneouvering speeds - one of the difficulties experienced when too big an engine is fitted. Ignore that bit if it is not in a Centaur, but the low tickover is worth investigating. Incidentally I have the previous model Volvo (2030) in my Bavaria 37 which is twice the size and dispalcement of a Centaur and it is more than adequate.

[/ QUOTE ]
Sorry for misleading. The D1-30 is in fact in a Beneteau Frst 345 where as far as I can tell it is well spec'd.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

[ QUOTE ]
When you say vibration do you mean that when idling the engine shakes around a bit on its mounts quietly...or does it sound like its vibrating and makes lots of rattly noises?

[/ QUOTE ]
It is very much the latter whereas in my mind it should be sewing machine like.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

Thanks for clarifying that. Had me a bit worried!

Anyway, like others not convinced it is a drive plate problem. Hope you get it sorted.
 
Re: \"Drive plate\" in a diesel. What is it, what does it do and how mu

Interesting. A second opinion has highlighted a not-obvious failed engine mount. Mounts to be replaced next week. Will report on result. Thanks all for opinions so far.
 
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