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MG MGF Technical - Hydragas: I've Got That Sinking Feeling

Hi, all,

Okay, either I don't know how to spell Hydragas or there's nada in the archives.

If you recall, I got the suspension pumped in my 97 F maybe a month ago. For a week after, I religiously measured arch to hub with no discernable difference. Imagine then, walking towards the bonnet end in a big flat carpark and getting a sinking feeling.

Yup, nearside an inch lower than the nearside.

So, questions twofold: how does one ascertain where the leak is and how expensive might it be? Spheres, etc.

On another note: things to be done this weekend... if anyone is interested, I'll snap some pics:

o Rear compliance washers (2)
o Front track rod ends (2)
o Shock absorber bushes (8)
o Mudflaps (4)

Thanks again for your advice,
Col
Colin McIlwaine

I had to have a Rear hydragas unit replaced a few months ago,the MGF Center in Wolverhampton did it for around £110.
dk

It often is the rear sphere that fails Col, so pull of the rear wheel and inspect as far as you can the hydragas sphere tucked up there in the wheel arch (much of it will be obscured by the wheel arch metal work unfortunately. :o( If there is any evidence of a fluid leak, then it is the sphere that has failed.

The MGFC would be a good place to start looking for replacements...
Rob Bell

Rob, as always, thanks for your advice.

I've spent the last while checking out Dieter's site*, reading up on this stuff... more Qs:

If it's a tiny leak (took maybe three weeks and 1200 miles for her to drop an inch), will fluid be visible or will it evaporate too quickly?

Is it more likely to be the sphere(s) or the interconnecting pipe?

(Stupid idea spot: could one accelerate the pressure depletion by whoring around a roundabout several times (the wrong way in my case) or jumping up and down on the passenger side cill?)

What's the difference between Trophy spheres and standard spheres?

Ta,
Col

*Ich fahr nur noch im Dunkeln... classic, Dieter, absolutely classic ;-)

Colin McIlwaine

Colin,

Could you please fire the pics over from your to do list, if you have them. I am very interested in teh first three points, not really in the mud flaps

freekstyle@lycos.nl

Thx
Freek
Freek

Sorry Col - didn't spot this reply! :o/

>> If it's a tiny leak (took maybe three weeks and 1200 miles for her to drop an inch), will fluid be visible or will it evaporate too quickly?<<

Good point. Very very unlikely to spot a fresh fluid pool under these circumstances. The best you can hope to find is evidence of a fluid leak or crystalised antifreeze around the sphere - which will be difficult with the subframe still in the car.

The workshop manual isn't terribly instructive on how to diagnose the problem - rather it is a diagnosis of 'exclusion'

>> Is it more likely to be the sphere(s) or the interconnecting pipe? <<

Odds are that it'll be the sphere unfortunately. :o(

>> (Stupid idea spot: could one accelerate the pressure depletion by whoring around a roundabout several times (the wrong way in my case) or jumping up and down on the passenger side cill?) <<

Erm - no idea!!! LOL

>> What's the difference between Trophy spheres and standard spheres? <<

Trophy spheres have a different Nitrogen pressure and I suspect that the valving will be different too. Trophy displacers have a different part number to the standard items. It would be very unwise to mix standard spheres with Trophy ones... but if you wanted a complete Trophy set up, then now's a good time to go for it :o)
Rob Bell

Freek,

No problem: I didn't get a chance to work on her this weekend... *huge* hailstone showers off and on. Maybe next weekend ;-)

(Rob/SF/Tony/Dieter/etc already have (some of?) these topics covered if you're in a hurry.)

Rob,

Thanks for your advice. Against my better judgment, I'm gonna book her into my local (and what do you know, only) Rover dealer, see if they can sort out the Hydragas.

In the meantime, I'll be at the bushes/TREs/RCWs/etc. Here's a thought... I know I must get the alignment redone after said work, but will the fact she's sunk on one side affect the resetting?

Cha-cha-ching,
Col
Colin McIlwaine

Just get the re-alignment performed once all the repair work has been completed Col - then it doesn't matter what happed before the work was completed.
Rob Bell

Stunning.

Remember my rear bell crank problem a while back, Rover said they couldn't look at it for, like, three weeks or something.

Just called them regarding the Hydragas. Tomorrow, if you can believe it. I can't.

Amazing. I'll let y'all know how she gets on.

Col

PS Rob, my concern was I'd be pottering around with bad alignment, waiting to get the Hydragas sorted. There was a topic a while back about getting the alignment done *as soon as possible* after complicance washer installation/TRE changing and/or driving really slowly and carefully to your nearest alignment center.

That said, the front Eagles are very badly scrubbed (on the inside), so they're gonna need replaced anyhow. Dear God.

PPS Top down first time this year. Brrrrrrr!
Colin McIlwaine

Help! I've got hydragas fluid dripping out of the box section just under the front of the driver's door. Can't find where the heck it's coming from as all the pipes and spheres at the front look dry as far as I can see with a torch.

Any ideas? Could it be tracking forward from the rear nearside shpere?

Dave.

dave

Hydragas fluid or coolant Dave? I guess that if the ride height is dropping then that question is a no-brainer!

Col, ah, I see where you are coming from now. I guess the prompt service action from your local neighbourhood Rover garage should get things sorted so you don't need to worry about getting the tracking reset ;o)
Rob Bell

Dave,

I've noticed (since I 'joined' this board) that whenever someone has a specific type of problem, the problem will magically appear soonafter on a number of others' motors as well. So...

... I fully expect my parking space to be flooded with hydroelastic fluid when I go out this evening ;-)

God help us if someone reports they're wheels are starting to fall off.

Col
Colin McIlwaine

Duh. "...their wheels..."
Colin McIlwaine

Thanks for the reply Rob.

Definitely Hydragas fluid, and the susy is dropping so bit of a hint there then!

I wouldn't mind if it was coolant 'cos I'm losing that as well. Good of MGR to colour the fluids differently so you can tell which system is dumping on the floor eh?

Any thoughts as to where it might be coming from?

And Colin - you're absolutely right. I'll post it here when the wheels fall off!

Dave.
Dave

All,

I am speaking to you today with a heavy heart.

I left her into MGR yesterday to see if they could ascertain the cause of her Hydragas leak. No joy. (They did however refill her for free.)

The *only* course of action they are willing to take if she sinks again (which she will) is to replace the *entire* Hydragas system, all four spheres and interconnecting pipework, at a whopping 1300 euro.

No, no, and no again.

Maybe to be continued,
Col ;-(
Colin McIlwaine

Okay, I've got it together.

I knew what I was getting into when I bought a (then) six year old car, but I really cannot justify spending the same amount I have during the last year, during the next year. And it would probably be more, she's not getting any younger.

Worse, it's not even darkside, it's just keeping her on the road, dammit.

So, decision time. Whilst waiting at MGR yesterday, I took a spotless late '02 TF 115 out for a spin. With a relatively generous px on my '97 VVC, I'm sorely, sorely tempted.

Okay, it's not going to have the same kinda poke as a 1.8 VVC, but the road tax and insurance will be cheaper and (surely) I won't be pouring cash into it. Eighteen months left on the warranty, etc, etc.

Any comments welcomed, particularly from anyone who dropped from a 1.8 F to a 1.6.

Col
Colin McIlwaine

Col, there really isn't any reason to have to replace the entire hydragas system on your car. It's connected front to rear, with each side being independent of the other - so tops, you're looking at one side needing replacement.

Not sure why your dealership is having such difficulty in identifying the problem? Trouble is, to investigate properly will take some hours of labour - and that alone will work out reasonably expensive...

TF115? Sounds like a good option to be honest. Not tried the car myself, but the 1.6 K-series is a honey, and isn't all that far off in terms of power behind the 1.8. Torque is where you loose out. But perhaps you can revisit this at a later 'Darkside' induced date... remember that the 1.8K will slot straight into the 115's engine bay! ;o)

Personally I'd hold out for a 135 if you can afford to: it offers a good deal more standard kit (the 115 is pretty sparse), and is rather peppy in the performance department!
Rob Bell

Thanks, Rob,

Re: Hydragas replacement, I know. I did point out that I was not totally unversed in the intracacies (sp) of the F's suspension system; I believe their point was that they could not 'stand over' a *partial* refit. Racket? Maybe.

Re: TF135. Agreed, the 115 spec is a little light, but those extra 200cc means a substantial hike in tax/insurance. Anything else I can retrofit... oh no, darkside's a-calling again ;-/

Hey, just noticed, no ABS on 115/135?!

Col

PS If I do go down this route (and who am I kidding that I'm not going to), F-related things up for grabs (and these are all as-new for a Mk1 F where applicable):

o Clear front indicators inc amber bulbs (SF, if I'd've known, I would've donated these ;-)
o Rear hub bearing (1 off)
o Track rod ends (2 off)
o Mudflaps (4 off)

Let's say 1/2 B&Gs RRP + P&P from Ireland.
Colin McIlwaine

>> Anything else I can retrofit... oh no, darkside's a-calling again ;-/ <<

LOL! Just about everything Col ;o) The whole interior, the electric mirrors, the colour coded door handles and mirror backs, the missing horn, the volumetric alarm sensor, decent wheels etc etc...

All available from the 'usual suspects' at very agreeable prices ;o)
Rob Bell

Colin, just a suggestion. Why not take a trip over to Blighty for a couple of days and let Techspeed have a look. Whilst there you can get the lowering knuckles. And if it comes to the worst and you need to get the spheres replaced there's alway the option to upgrade to the Trophy ones.

Ralph
Ralph

This thread was discussed between 13/04/2004 and 21/04/2004

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