The magic pump for the MGF and MGF Trophy suspension works


When I purchased my second hand 1996 built MGF in October 1998 I nearly knew nothing about the combined spring and damping system developed by Sir Alex Moulton.
Nearly nothing, only that my MGF must have a problem with his current suspension setup.
- It was wobbly without moving the steering from right to left on accelerating.
- At about 80 mph the steering began to shake and on windy conditions the same happened
- I got fear to travel faster then 80mph because it nearly was blown off the road.

What now ? Reject the car ?
No, I'm an engineer ! Not educated for car works but with wide skills in several mechanical technologies. I should give up ? Never ! I tried to find friends succesful on the Internet Michael Bender showed me with his Website whats going on there, Great !!
I explored the UK based BBS, found hundreds of entrys on suspension threads and got my first blame there on asking stupid questions :
' is that for the hydragas system used pump equal to a Citroen cars pump' and things like that. ;-)
My MGFs suspension was corrected by a friendly dealer. I learned a lot at the BBS and while serving my own technical based Website.
The suspension system got my favourite technical discussion term. I ever used to find out how things work at my cars not only to repair it myself, but as a hobby.
This mystery hydragas system must be worked out.
It lasted about 3/4 years until I got contact to Carl, from Sweden. He was interested too in collecting each and everything related to the MGF and had already a lot of experiance. Rob Bell, Ted Newman, Thomas Ohms, John Thomas, Tony Smith, Kes from Kidderminster and Roger Parker and some more. A kind of team of well known names put their little bit to this summary of one year research on things that nobody else in Germany was seams to be interested in.
Now, what is it good for ? Only for my fun on finding out things that nobody 'should know'.
I did it and do it because it is possible.
The other reason: Improving my english language skills. Thats all.
See this Webside and enjoy it.

Principals of the MGF hydragas suspension

Rob's webside on hydragas suspension principals

Ride hight, the vital term for the MGFs riding comfort

Lowering by works at the standard knuckle set

Building and use of a home made Hydragas Pump

Pump use at an LHD MGF, some data

Cut through a broken MGF Hydragas Unit

Change of a blown right rear Hydragas unit #1 blown right rear Hydragas unit #2

Building and use of a home made evacuation system [under construction]

MGF Lowering with the simple pump set (pressure and evacuate)

MGF bump stops installation (pressure pump used)

Four wheel alignement of the MGF [under construction]

Pump Gallery

Liquid Levers Pumps

simple version *pressure only* at Liquid Levers and .... the very Hydravac (2004) including vacuum function, 18G 703Q .

© 2001 Manfred Kribbel .. from inside

Spyros :)

Same Pump at Hanah's workshop in NZ

Liquid Levers Innovations,
Unit1, Mountfleurie Ind Estate Lerven, Fife, KY8 4AX, Scotland UK

Vacuum Hydrolastic
Suspension Pump
[Part-number: HYV - Rover ref. 18G703Q]

1: Initial procedure
Fill the machine reservoir with the correct fluid
Set the valve to pressure
Make sure that the vehicle is on level ground with the handbrake off
Remove dust cap on car hydrolastic / hydragas connector
Fully slacken tap T (if available) by turning anti-clockwise, also
slacken bleed screw by turning anti-clockwise two turns
Screw on the body of the low loss connector as far as possible (by hand !)
Operate the pump handle to fill the plastic tube, thenm close valve T (if available)
Connect the vehicle hydrolastic / hydragas fluid by turning tap R fully clockwise
2. Raising trim height
If merely increasing trim height, set valve´to pressure and pump up to the required height / pressure
3. Checking trim height
Roll the car back and forth and bounce the suspension before checking the vehicle trim height. Adjust downwards, if required, by sliding the valve to depressurise until the required height is achieved.
4 Depressurise the System
Slide the valve to depressurise
WARNING - Both the pressure and vacuum gauges are isolated during the depressuriseing sequence. Before opening the system on the vehicle, slide the valveto pressure to check the pressure is zero
5. To vacuum the system
Depressurise the system; making sure no pressure is left by returning the valve to pressure and checking that the pressure gauge is at zero
Slide the valve to vacuum and operate the pump till the required vaccum is reached.
The fluid from the vehicle will be returned to the reservoir. If there is any doubt about the fluid drawn from the vehicle, empty the reservoire and dispose of the fluid correctly - treat as brake fluid or anti-freeze.
WARNING - If pressure is within the system if the valve is put to vacuum position, damage to the vacuum gauge may result.
6 To releive Vacuum
Slide the valve to depressurise. Fluid wil be drawn back to the system from reservoire. Make sure that there is adequate fluid in the reservoire. Remember only to use the correct fluid.
7. To pressurise the system
As step 2

Leyland tool number 18G703 later 18G703V

Might be similar to this one

Tims pump (same as ALBA )

Easy grease pump with bolt on truck tyre adapter might work to, as shown by Andreas K.

See at Lumatic i.e E500

See what charless from the UK has got in 2010 at the MGF Register Forum Y 01.2010

It is an oil gun with a T-piece to accommodate the unnecessary luxury of a pressure gauge (both parts from c.£33 delivered). The low loss connector made by Schrader (possibly cheaper source) came from c.£50 delivered. The connector's thread is 3/8 UNF. Many oil guns are available from well under £20 (but I already had one), finding one with the 3/8 UNF gives you a straightforward screw together tool. I added a couple of turns of plummer's PTFE tape to proof each screw connection. Hydraulic threads tend to be British Standard Pipe (BSP) or Unified Fine Thread (UNF) The common sizes of which can be bought in one tap & die kit from Machine Mart (kit CHT304 includes the metric range as well as BSP and UNF c.£38).
This beast can probably pump watery liquid well over 2000 psi safely, it is rated at c.6000 for oil - I only need c.400 psi for the Fs - so I can pump them up in the cold weather and get much better headlight beam pattern, then let them back down again in the summer.

2003 enhenced with Liquid Lever connector :)
Gas Chuck (Accumulator Charging Valve)
Parker 0.305-32 UNS (No 8708150000 )

Low loss connector from PROSOL (found by Chris B. © 2008 )
LLC4690 for about 30 Pound
plus Lumatic Oil Gun (Type OLGH/CV does 8.500 psi (600 bar)) and hydraulic bits from
Jon used the Lumatic E500

© 1998-2001 Carl the DIY suggestion came from Sweden.

© 2000-2001 Dieter DIY

Construction works hydraulic jack. ... good for 300 bar ;)
Modified due to the hints on this site for JM in Argentina. Looks great and much better then those below here.

Valter Fernandes, fellow F'er from Portrugal used an old hand pump to open Aircraft's engine cowls.
Mmachined adaptor to fit on the hydragas nipples and throughout cleaned the pump and flushed the circuit, till it was free from any oil.
Jjust had to imerse one end to the bottle and to screw the other end to the hydragas system.

© 2000 Don Liang DIY

latest product is a test pressure pump for plumbers, like this one up to 30bar (480psi)
together with a cheap low los valve for bicycle dampers like this one from SKS for USP/MSP pump
An adaption of the SKS valve to the testpump needs to be sourced.


According to the paperwork that comes with the Hydragas pump, these are the cars with Hydragas and Hydralastic suspension and their front wheel trim heights... [Thanks to Andy]

Hydragas type Trim Front Height rear Tol. Pressure connector
MGF 368mm 358mm 10mm 450lb/sq" approx. under bonnet temperature correction:
0,6mm per degree (17° C)
front linked to rear
(LH or RH)
MGF Trophy 348mm 338mm 10mm 450lb/sq" approx. under bonnet temperature correction:
0,6mm per degree (17° C)
front linked to rear
(LH or RH)
Metro 1980 - 1990 12 7/8" 12 6/8" 3/8" 420lb/sq" under bonnet & front of rear L/H wheel independent front suspension units; rear units linked
Metro 1990 onwards 341mm N/A 10mm N/A lb/sq under bonnet & front of rear L/H wheel

independent front suspension units; rear units linked

Ambassador 14 1/2" N/A 1/4" 350lb/sq appox. under bonnet  
Allegro to car no. 226629 14 3/4" N/A 3/8" 340lb/sq appox. under bonnet  
Allegro car no. 226629 onwards 14 1/2" N/A 3/8" 340lb/sq appox. under bonnet  
Maxi - 1970
Maxi 1971 - 1977
Maxi 1978-
14 1/8" N/A 3/8" 245lb/sq"
under small panels on boot floor  
Hydralastic type            
Mini up to Dec 1965 13" 13 1/2" 1/4" 263lb/sq" under rear of car  
Mini from Dec 1965 12 5/8" 13 1/8" 1/4" 282lb/sq"  
Mini Clubman 13 1/2" 13 1/2" 1/4" 292lb/sq"  
Princess 14 1/2" N/A 3/8" 350lb/sq" under bonnet  
Princess Mk1 13 5/8" N/A 3/8" 230lb/sq" under bonnet  
Austin/Morris/Wolseley 1800/2200 14 7/8" N/A 1/4" 245lb/sq" under bonnet  
Austin, Morris, Wolseley, Riley 13 5/8" N/A 3/8" 205lb/sq" under bonnet  
MkII 1100 & 1300 with arch rear spring 14" N/A 3/8" 195lb/sq" under bonnet  
MG Normal Air
(I assume this is the 1100 / 1300)
13 5/8" N/A 3/8" 220lb/sq" under bonnet  
1300 GT 13 5/8" N/A   205lb/sq" under bonnet  

Names for methylated spirits around the world
In the UK, Australia, and New Zealand, metho is called methylated spirits. In the US it is called denatured alcohol. In Europe, it may be called spirits, brennspiritus (Germany), alcool a bruler (France), sprit (Norway), spiritus (Netherlands). It is generally available in hardware stores, supermarkets, service stations, and camping/outdoors stores.

mixture of 1/3 white spirit + 2/3 pure coolant gives useful stuff for an MGF suspension

Never store Hydragas Fluid in a 5l metal can. p/n GZS1486 ( GZS2000, VDS000030 ) Hydralastic fluid
They will rust ! This are two images from an original can.
(c) Carl, from Sweden

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