I was reading another post which mentioned about the incorrect engine mounts being used having been mixed up with rear bumper mounts on the MK2. I have a Daimler V8 which uses the same mountings. I had the engine mounts and rear support bush and gearbox mount renewed which left me with a vibration which is way too bad to ignore. I am wondering if bad engine mounts could cause a vibration problem? The propshaft was reconditioned and balanced with new bearings. It is really spoiling the car at the moment.

 

On the V8 as I have just looked at the online Heritage parts list the engine mount is part number C4794 and it looks like the rear bumper mount is a BD9927. C4794 is the same engine mount used on the S Type and BD9927 is the same part number for the mount used on the rear bumper.
Having said that they seem to be identical. If you go to SNG for C4794 you get three options one is an upgraded version. https://www.sngbarratt.com/English/#...rnedDown=false
For BD9927 they list it as an engine mount but the item looks identical to C4794. Not sure if there is a physical difference. https://www.sngbarratt.com/English/#...rnedDown=false

I had an engine mount let go on me a couple of years ago at idle on the driveway. The metal sheared from the rubber and the engine moved allowing the fan to go through the back of the radiator. Cost over £500 to have the radiator re-cored. I replaced the mounts with standard ones from SNG but I too have a vibration at idle speed 600 rpm. Feels like the engine is rolling excessively when I am sat at traffic lights. As soon as you go above 1000 rpm then it all levels out again. I am keeping an eye on the mounts but I think in the summer I will change to the uprated mounts that SNG sell part number C4794U https://www.sngbarratt.com/English/#...%20%60C4794%60

 

If the vibration is present when the car isn't moving and the gearbox is in neutral, it's worth looking at the engine mounts. If it is when the car's moving, it may be in the drive train.

 

The mounts I fitted were numbered C18556 and Robey have these on their site with same number for bumper mounts.
The engine idles great now and there is no bad vibration revving static up to 2500rpm.
I had the prop balanced as I said so it cannot be that out of balance. I had the rear end up on stands and ran the drive train and I could not see anything out of balance. The engine was a little rough then so caused some vibration but that is now fixed so I eliminated the engine. The rear stabiliser (new rubber) was reset to correct spec. ie. no load just snugged up and locked off. The prop alignment was checked and I believe is correct.
The car was new to me although I did drive it and had no vibration until I changed all the rubber bits when it became apparent immediately. I also changed the anti roll bar with uprated unit and new rubbers.
I thought maybe the wire wheels were bad so had them balanced and although 3 were "off" they were balanced with some weight and the vibration was still there. I have since been told to balance them on the car with brakes off by wire wheel experts as dynamic balancing not the best way. I have 4 new wires but not for this car (wrong colour) and I have to buy 4 tyres and hope they are not scratched when fitted....... last resort!
I am clutching at straws with the engine mount theory.
I may just jack it up again and run it to recheck now the engine is sweeter. My local guy will not do this on the workshop ramp for safety reasons.

 

There's also the rear mount behind the gearbox to check that it's installed properly. I had a vibration in my Mk2 years ago. I checked the prop shaft and found the splined joint was misaligned. I corrected it, but the vibration was still there. In the end, I found a bulge in the centre of the tread on one of the tyres. I replaced the low speed rating Pirellis with a set of correct Avons and the problem was resolved.

Vibrations can do more than annoy. They can damage parts in the drive train such as the alloy casing of the overdrive, especially the spool piece that connects it to the back of the gearbox.

A final point, running the car in gear with rear wheels off the ground : use more axle stands/blocks of wood than seem necessary and point the car towards an empty space. And generally be very cautious.

 

"In development the Daimler XDM2 had the latest Borg Warner type 35 automatic gearbox, and proved very successful. Its major problem was a throbbing and intermittent drumming & vibration, which Jaguar discovered was caused by flexing of the gearbox transmission unit. The problem was quickly solved by fitting a stiffener plate between the bottom of the bellhousing and the sump."

Ensure all is in sound condition in this area.

 

The car was "sound" when I first got it. The vibration started as soon as the rubber parts were replaced. I have to assume that the problem was
a)caused by the work done or
b) became apparent because the rubber was new not old.
The propshaft joint was marked so went back correctly.
It is concievable the wire wheels were knocked out of true as I live on a rough track. The steering did rattle along this track and replacing the two bushes and thrust washer has cured that problem.
The gearbox was fine. I did not fit the centre support spring and rubber but the guy who did it is normally good and not a bodger.

I will be taking all precautions nad hope to get some video

 

The newer firmer rubbers might have excited the old problem mentioned above. Just check the stiffener plate for integrity sake. It might have zero to do with your issue but it's worth checking. Sorry I have no picture.

 

Perceived NVH is very sensitive to engine mounts. They have become very sophisticated in modern cars. Indeed, looking at modern ones, it's remarkable that the simple bits of rubber worked so well. I've read of people who've had the bright idea of replacing their engine mounts with poly bushes for 'performance.' It's a total disaster for anything other than an out and out track car and a doubtful advantage for racing. So, yes, the new bushes may have stiffer rubber and have either caused the problem or highlighted an existing one. If it's possible, it may be worthwhile to check with the supplier about the rubber used or if they have had other customers with problems.

 

Thanks, I will check this.

For the record I had to look up NVH!

 

Is the vibration when you pull away and/or when the box changes gear? If so then check that the propshaft has been aligned if its the two piece type.

If this isn't done it can cause a really bad vibration in the above situations (especially when pulling away).

 

The vibration occurs at about 25-30mph and gets worse at 40mph. It is bad enough to cause me concern. The prop shaft has been completely refurbished and balanced by a specialst. I swopped the propshaft over from my spare car which had not been refurbished and whilst the settings of the centre support were different ie. lots of washers above the support plate I still had a vibration. I then refitted the newly refurbished original propshaft and still have the problem. I made the propshaft alighnment tool to get it level in both planes although my gargage guy said the UJ's should eliminate any minor misalignment.
When I took delivery of the car it was driven for 40 minutes to be registered in Ireland before any work was done. I did not have a problem with vibrations and was driving at a normal 40-50mph on country roads.
Only when I had the rubber mountings renewed I immediately noticed a problem driving home. So I am chasing shadows with wheel balance, propshaft etc.
It is not a steering wobble as in unbalanced front wheels but more of a whole car vibration.
As the engine does not vibrate in nuetral I have to consider this is a possible gearbox problem.
I will be doing more tests and report results to hopefully zero in on the area causing this.

 

Check the integrity of that stiffener plate as in post No 6.

 

More questions than answers.
Does the vibration still continue if you drop the gearbox into neutral at 25-30 mph and coast with the engine on?
Do you get a vibration if you rev the engine up a point where it would be doing 25-30 mph when stationary in neutral on the driveway?
Might sound silly but have you tried changing the wheels around, putting the fronts on the back and backs on the front?
Has any work been done to the gearbox prior to you buying the car? Might the torque plate or torque converter but unbalanced inside the bell housing.
You said you have had the tyres and wheels balanced, is this because you have put new tyres on the car?
If they are the original tyres was the car sat around for a longtime before you bought it? This might have caused a tyre to have a flat spot which puts it out of balance at speed which might not be found on a low speed balancing machine without the tyre under load.
When you had the wheels balanced did the shop use cones to balance the wire wheels or did they balance them the same way you would balance a steel wheel. You have to use cones to balance a wire wheel because of the way it sits on the splines rather than the back of the wheel being against the hub. Glyn has some diagrams of how to balance a wire wheel.
As I said more questions than answers but with more information we can rule out certain things. We are all here to try and help.

 

Dayton method is proven wrong even with their wheels. Smoothride kits are available at a reasonable price. MWS sells a beautiful kit for balancing centre lock wheels but is intended for a tyre shop (Very expensive). Both Rob (Cass) & I own Smoothride kits. Remember Jaguar/Daimler use 52mm splines

 

 

Morning guys.

I can advise I have driven the car after delivery to me and I would have noticed the problem right away so it was not something done prior to my ownership as far as I can tell. The car had been dry stored for some time. It has been "restored" by a professional Jaguar business some years ago but the quality of the work is pretty disgusting as I have a lot of invoices paid by the previous owner and I suspect they did not realise the work was so poorly done. I have remedied quite a lot of problems.
I had the wheels balanced after buying an adapter kit as above. The resin model not the aluminium one. I got mine from Fosseway Performance. I was there and watched the process. Some wheels had quite a lot of weight added but remember I had driven the car on these wheels/tyres and no bad vibration before the work on rubbers being replaced. After balancing thre vibration was still there. I have swopped wheels over. The vibration is whole car.
As I have said I have a set of brand new MWS wires but would need to buy 4 tyres and I am not yet convinced these are a problem.
I have spoken to a wire wheel specialist in UK and he advised me to manually balance on the car. To have them "repaired" is more expensive than buying new especially with shipping costs.!
I will try the coasting test.
I have revved it stationary up to 2500 revs. It did have a misfire which I cured but I will do that test again to be sure.
I appreciate all the advice - it is a lonely frustrating problem so nice to have back up.
I am considering replacing all the rubber fittings again just to be sure it is all fitted correctly. I have an altrernative local garage with a lift so would not use the same guy to fit them.
Of course something else could have broken/failed at the same time as rubbers were replaced but that would be a big coincidence.
I am pretty sure there is no gearbox reinforcing plate fitted. Can these be bought?

 

Do you have a Parts Manual? Do you know the part number?

If it is C22112 there is one on Ebay at present.

Non Jaguar spares are hard to come by for the Daimler V8

 

That part is also in stock at David Manners. Either he or the eBay seller might be able to say if it is the stiffener. David Manners began as a Daimler enthusiast so he may be the best place to start.

 

I would back Peter on a chat to David Manners. An absolute & helpful gent.