Leaky ram and electrovalve!

Unread post by **Dommo** » 10 Jan 2010, 13:07

That does make it a lot clearer, thanks. Is it not possible to fit a new alloy part? Or is finding the alloy part an impossible task?

Cheers.

Unread post by **CitroJim** » 10 Jan 2010, 13:10

The latter Dom, an impossible task

Even the O rings are only available as part of a new valve and they cost a lot of money.

I reckon in the future, we may need to have a batch of bodies made up as all the other bits can be transferred.

Unread post by **Dommo** » 10 Jan 2010, 13:20

Surely you can get a pack of O-rings from somewhere? Halfords sell them in all difference sizes. If you knew the size of the o-ring I'm sure you could get them?

Unread post by **CitroJim** » 10 Jan 2010, 13:26

Yes, indeed you can Dom but you must ensure that any O ring you use is LHM-proof. LHM can eat some types of rubber in a very short while. Only certain synthetic rubbers such as Viton are LHM proof and this is why rubber seals and rubber hoses are special and so designated by having green lines on them...

use any old rubber at your peril...

Unread post by **Dommo** » 10 Jan 2010, 13:36

Fair enough

Could test an O-ring by putting it in some LHM for a few weeks or so and see if anything happens.

Unread post by **CitroJim** » 10 Jan 2010, 13:39

Yes, that's an excellent method of checking compatibility with LHM

DickieG · Unread post by **DickieG** » 10 Jan 2010, 14:06

Dommo wrote:I'll get the ram fitted in the next couple of days

Prior to starting work check on the condition of the ram supply hoses as they tend to rub against the inner wheel arch causing wear to the hose sidewall. New hoses costs £35+ each, if you need to replace one of them the parts diagram is incorrect in that what on the diagram is the longer one of the two is in fact the shorter one in real life.

addo · Unread post by **addo** » 10 Jan 2010, 19:00

Can these flex hoses be remade using the old ends, like the way people do field repairs for heavy machinery?

Unread post by **Dommo** » 10 Jan 2010, 19:26

Cheers dickie I'll have a look at those in the light another day. addo we should get some goodridge braided hoses for them

Unread post by **Dommo** » 10 Jan 2010, 22:41

Here's the new electrovalve from Savoy Garage. Certainly looks in good condition in my opinion, especially the alloy bit.

Can I literally just swap the alloy part and the bit above it. This bit:

Or am I best swapping the whole thing in the picture? The sphere looks a bit passed it though.

Cheers.

Unread post by **CitroJim** » 11 Jan 2010, 09:02

What car did that block come off of Dom? If it's from a MK1 Xantia or XM then it won't fit a MK2 Xantia as the blocks are very different with regard to suspension cylinder pipe flare sizes and more majorly, there will be only one 3.5mm pipe on a MK2 whereas on a MK1 there are two. They are not interchangable.

Easiest way to tell at a glance if it is from a MK2 is to see if there is a bleed nipple on the body. I can't see one in the pictures and I think I can see two 3.5mm pipe holes so I reckon you have a MK1 version there.

No worries as the electrovales are the same. Gently try to remove the valve by using a socket on the top 16mm hex on the end of a long bar and easing GENTLY. If you are lucky, the whole valve will unscrew and come out of the sphere block. Note that the coil (the bit with the electrical connector on it) will rotate freely to allow the valve to be fully unscrewed from the block.

If you are unlucky, the top part will unscrew independantly of the body. No worries, just keep gently unscrewing until the top comes right out. Then carefully lift off the col and retrieve the innards of the valve from the alloy body, noting the order of the springs , shuttle and slug.

Then, use a 24mm deep socket to remove the body. Take care as it is SOFT alloy. You may need to grind and shape the socket to fully fit the 24mm hex as a standard 24mm socket may be too thick to fully sit snugly down on the hex.

Good luck...

Never judge a sphere on looks. That one looks like it's been at the bottom of the sea for a thousand years but may be absolutely fine. Only a pressure test can confirm it's condition...

Unread post by **Dommo** » 11 Jan 2010, 10:34

I think he said it was from an XM, there are definately two fairly large holes for what looks like hydraulic lines, one at the top next to the electrovalve and one at the bottom opposite the top one, on this picture:

So theoretically Jim I wont need to remove any spheres to do the required repairs.

One concern I did have, do you think old LHM could damage the new ram seals? But then again it's been leaking so the LHM is probably fresh down there! Although actually does it pump around like a circuit as apposed to like a conventional braking system, where fluid in the caliper pretty much stays in the caliper? And therefore it should have the same condition LHM as to what's in the reservoir..

Cheers.

Unread post by **CitroJim** » 11 Jan 2010, 12:58

It's easier if you do remove the sphere to do the job Dom as it improves access no end. Remove the spare wheel carrier as well. Also, as that sphere block is from an XM, it will not be compatible so you won't get away by changing the whole sphere block over. As I say, the big pipe flares are different and you will find there is one too many 3.5mm hydraulic pipe holes on the XM block!

The LHM condition should be assessed as you don't really want dirty and worn-out LHM running into a new ram.

The easiest way is to extract a small sample from the reservoir and have a good look at it. It should be bright green and crystal clear. If it's yellow, brown or opaque then it's old and must be changed. I'd also check the condition of the LHM filters inside the reservoir and clean those carefully.

Then, if the LHM did look dirty, run on Hydraflush for at least 1,000 miles to clean everthing up before refilling with fresh LHM.

Unread post by **Dommo** » 11 Jan 2010, 13:55

Ok thanks Jim, I'll have a look at the LHM but when I bought it the stuff in the reservoir was bright green. Whether that's because he'd just topped it up or not I'm not sure. He also said he'd cleaned the filters already.

Is the stuff in the reservoir circulated around the whole system regularly? Ie is it a good indication to overall LHM condition?

Cheers.

Unread post by **CitroJim** » 11 Jan 2010, 17:05

The LHM is in constant circulation Dom, the only places it's not are in the "dead ends" leading to the brake calipers. This is often why when you bleed the initial LHM that comes out is a horrible yellow before the nice green starts flowing...