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MG MGF Technical - Ride hight dropped again

according to my 'curious' Hydragas System repair job several weeks ago, (I changed the rear right HydraGas-Unit myself and pumped it up with my 'Carls-pump')

Now what happened:
Everything seamed OK after rework the probably included air in the system by my dealer.
No idea about the milage I drove, may be 2000km.
When I got back from a 600km trip in the middle of December, I realised for new that something got wrong with ride behavior. I had no chance to check it, because of holiday until yesterday...

I found the car yesterday with dropped REAR-RIGHT ride hight.
dropped down app 35mm. (from 355 to 320)
The front was OK ??

I thought 'sh*t' something must have broken, may be a bracket or loose screws or what..
I lifted the car yesterday (wheels free), but did nothing else until this morning.

Now, because works need the release of the hydra-fluid I put the car back down and just wanted to open the bonnet for starting the works. But I stopped then because suddenly the hight front to rear looked now equal.
Hm, I bounced and bumped front and rear before I measured and found, as it should be, only the standard difference of 5..10mm between rear and front.

But the complete right side is now app 15 to 20mm dropped.
No green stuff on the floor.

>Grrr< Lets see what the pump and the pressure in the system says.
If that replaced Unit got damadged again .... <grrrrr>

See you later.

@@ Scheisskerle, Mistbienen, Fickpickel, Arschloecher, Scheissraben.

(Sorry but I need that this morning, like Dirkie with his head gasket(s). If you don't like it, then please read another thread) :o)

I really got angry !!!!! This f*cking Hydragas sparepart got indeed blown <GRRRR>

I had a look at the car this morning and found the ride side ride hight again 5 mm lower, (now 320 at the front, after bouncing.)
Then I lifted the car a little on right side to get the little to high hydraulic jack under the rear ends middle lift joint.
But already while lifting app. the first 10 mm I heard a noise like drinking Coke from an empty glas with a plastic pipe (Schluerfen). I stopped, looked under the rear right suspension and saw the green stuff dribble out and onto the garage floor.
SH*T. No more looking needed. The stuff is drawn out of the units lower diaphragma and now ahead the dust protection rubber) While lifting the car the suspension the piston and diaphragma gets down and presses the fluid out.

I do not know wether someone (without Carl) can imagine what crap job it is to change the rear right Hydragas unit :(
I did it. <grrrrr> more then 4 hours for an 48 years old petrolhead :( Nothing fits metalplates must be bended, two screws are not to reach with normal tools. That idiots of designer placed screws with nuts at the worst place where they could be used.

The part was replaced on 15th November and got blown 1 month later app. 19th december. I checked fuel bills and found that it only held for 800 km !!!!

How is such a crap possible ?
Do this Dunlop guys no final tests to that crap patented Moulton sh*t. ;-(

I am just back from my (friendly) dealer. Only the sparepart is covered under a part warranty (german law sais 6 month) My works are for the as*. No help, no change by Rover.
So I'll change it for a second time, for nothing !!!

But what shall I do with the third unit ? how long may it last until it blows ???
What if it needs 6 month and one day ????? :-(

Shall I purchase one or two or just 20 to do the final test for that f*cking production ???

I think everything at that car with the shortening 'HG' is crap !
The HeadGasket and the HydraGas things.

BTW does someone know the exact geografic coordinates of The Rover- Neuss and Rover-Munich offices ;-)
The coordinates of that Dunlop factory for MGF Hydragas Units would be nice to know too ;-)
I think I change the webboard and look for one where friends of Ghadafi or such subjects are to find ;-(

Good night Rover
They will get a similar written letter, promised !!

PS. where can I find offers for cheap cruise missiles :)
Ahhmmmm.... No flames on/for anybody here, but am I not right ?


welcome to the 2 hydragas failures Club :(((
I was luckier, as my dealer did the job and Rover paid.
If you look the bright side, changing the unit yourself is some kind of MGF mechanical experience !


commiserations Dieter- bad luck my friend.

Out of curiousity, what part of the 'sphere failed? To get the kind of irregularity of ride height, I presume that the nitrogen 'cell' failed?

BTW youare right- I don't know how to change the hydragas unit- and I don't want to find out!

Robert Bell

>I presume that the nitrogen 'cell' failed?

Rob, no, it is definately the lower one for the hydrafluid where the aluminum piston is fixed.

The free space between that lower diaphragma and the lower body (cone piston area) is protected by a third thin dust cover (rubber).
This free space got now filled with fluid and this was pressed out when I began to lift the car.

Anyway, I do not know recently wether the diaphragma itself or its fixture to the lower body got leaky.
I shut my garage door with a load 'bang' and did not want to research anything more at the MGF this morning.
May be I find time to disassamble it tomorrow :(

I can't cut that unit because it must be rejected to Rover by my dealer.

>I don't want to find out!
Hmm, its an interesting experiance but only once and not at the rear right side. ;-)


I just got the change ready. Only 2 hours this time. (including the for taking a bunch of digi photos)

The blasted Unit.....
As suspected: poor manufacturing quality. !!

The lower diaphragma can bee seen if the dustcover rubber is pealed back.
I saw small bubbles around the diaphragma. Yes bubbles, app. 2 to 3.5 mm diameter. some where blasted already and one could see the inner fabric.
(soon will come the photos)
The old unit gets back to my dealer tomorrow.
Hydra pressure for app 358 mm was app 29 bar on the Codrivers side (LHD).

So back on the road. I'll see wether I can reach the todays 'Froschenteich' natter with black oil fingers.

PS. Had before again a meeting with an MGF standing on the Motorways side. Engine problems at a VVC. He took no acceleration said the driver. Rover-Herrmann pulled him to their workshop. But thet will get another story :(


I know your feelings exactly, being a 47 year old petrolhead I have plenty of scars and marks from previous vehicle encounters, not all intended or wanted. I hope you have better service from this unit.

Roger Parker

This thread was discussed between 05/01/2000 and 08/01/2000

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