vibration, dolly1850 auto.

[dollyman]

hi all, i am new to this forum and asking for help
i have a vibration that i can feel in the car its not bad enough to shake the rear view mirror, but its there all the time.
i have checked the prop ujs and the centre bearing for play, and there is none at all!
plus there are no rust signs around them.
the car is a 1972 with only circa 26k on the clock.
the car has been fully polybushed, could this be the cause?
thanks guys any help would be appreciated

[cleverusername]

hi all, i am new to this forum and asking for help
i have a vibration that i can feel in the car its not bad enough to shake the rear view mirror, but its there all the time.
i have checked the prop ujs and the centre bearing for play, and there is none at all!
plus there are no rust signs around them.
the car is a 1972 with only circa 26k on the clock.
the car has been fully polybushed, could this be the cause?
thanks guys any help would be appreciated

Polybushes could be your problem, from what I understand, they come in different ratings. From similar to standard bushes, to rock hard. It is possible that could be your issue, especially if they are the firmer bushes. I have read other owners regretting going for full polybushing.

[markas]

Could be the engine or gearbox mountings. I acquired a 23,000 mile 1500, 1977 vintage, last December. First job was to replace all three engine mountings which had gone all floppy in the last 40 years! Made a very noticeable difference to the noise and vibration.

[Carledo]

If the vibe is present when the car is stationary, it's not drivetrain!

I too would be looking at engine and gearbox mounts, they get oil soaked and go soft and saggy with age leading to the engine or exhaust sitting on the rack or crossmember/subframe. This is more than enough to give you bad vibes!

Steve

[Triumph1300]

Is this vibration all the time, or only when moving?
If when moving, again all the time, or any specific speed?

[olr159w]

Just something to think about as I've recently gone through something similar.

I've replaced my engine and gearbox mounts because the sag was sufficient that the engine rested on the steering rack mounts on one side. I also suspect the original OS mount was upside down making it a lot worse.

So take a look at your relative engine position esp wrt oil pimp and steering rack

rgds

[tony g]

Also, have the rear wheels been balanced? Rears out of balance can give the vibes through the car. Mounts are worth looking at though as mentioned.

Tony

[dollyman]

hi guys, many thanks for the replies
i have checked the engine mtgs, and they are perfect, likewise the gearbox mtg.
they are all clean and dry with no oil leaks! (must be a first on a dolomite!!)
yes there is oil in everything
there is no vibration when when running and stationary.
there are four brand new dunlop tyres fitted and balanced.
it is there from 10mph upwards, and like i say its there all the time but not bad enough to shake the rear view mirror. you can feel it through the car.
there is also a very slight diff whine, but not half as bad as the mrs
so, any ideas? where to go next? the poly bushes are yellow in colour if that means anything?
thanks again.

[Mahesh]

The rearview mirror does not shake, but you can feel it when moving.

Does the feeling come from the steering wheel or seat ?

[dollyman]

The rearview mirror does not shake, but you can feel it when moving.

Does the feeling come from the steering wheel or seat ?

hi, from the seat.

[Mahesh]

Someone may know better, but the seat is bolted to the floor, if it vibrates, so does most of the car.

Tighten seat bolts down, and check the floor hasn't rusted through.

[dollyman]

hi, no the seat bolts are tight and the floors are in mint unwelded condition.
it feels like the engine is bolted to the body, but there is no vibration at all when not moving

[Mahesh]

Well, seems like most of the basics are covered,

I would say give it a very slow drive, (2mph) and feel if it's at all lumpy
or for a rhytm, and also go slowly round a (vacant) roundabout and check
for lateral movement, (preferably an empty car park, that way you can go
both sides).

[dollyman]

will do tomrrow, thanks again

[grahamwatson]

I have recently cured a similar sounding vibration on another classic (Volvo Amazon) by correcting the prop shaft phasing. This involves making sure that the front and rear yokes are in the same orientation, and have not gone "out of phase" by being incorrectly reassembled at the central spline.

Not sure if this is relevant on a Dolomite but it is a simple fix and may be worth a try if your yokes are not aligned.