Jump to content

Saracen Accumulator Charging


Mettlen

Recommended Posts

Hi All,

 

I want to charge the accumulators (piston type x3) on my Saracen, instead of a charging bottle and because I don't want to rely on getting bottles charged, I've bought a bought an air gun charging stirrup pump (3000psi capability). It has a microbore hose with a 1/8 bsp female coupling. The fitting on the end of the accumulator appears to be a schrader valve (can anybody confirm this?). So effectively I'm looking for a 1/8 bsp male to female schader valve adaptor. Has anyone come across one or know of a workshop set up to make one?

 

Alternatively, what equipment/methods (without spending hundreds of pounds) do you use to charge the accumulators????

 

(P.S. I recognise that the use of nitrogen is best practice)

 

Thanks in anticipation

Link to comment
Share on other sites

What you need is one of these:

 

They are available online, this is an example: http://www.tyre-equipment.co.uk/acatalog/Industrial_Valves.html

I found a complete kit at a show several years ago.

I use argon from our mig welder. I normally put in about 600 psi, then reduce it, using a pressure gauge with a rubber adaptor on it, to 500 psi.

Let me know how you get on.

schrader.jpg

Link to comment
Share on other sites

any decent hydraulic hose specialist company will make up an adaptor hose, I used 'Pirtek', based in Southampton...defineately best to use oxygen-free Nitrogen, as compressd air has moisture (water), in it,.... and as we all know, -water + oxygen + steel = rust, ...and believe ne you don't want rust in an accumulator... major safety issue! my local welding supplier 'lent' me a high pressure Nitrogen regulator, for about £10, and you can get a small bottle of Nitrogen, sufficient to allow a fill-up, and several subsequent 'top-ups', for about £40....

Link to comment
Share on other sites

Thanks guys - I've ordered the adaptor. At this moment in time I'm only doing a hydraulic system check for the brakes/steering. I'll also try starting the engine if I know I have brakes. Once I've done this the accumulators will come out for a full overhaul!!

 

Once again thanks!

Link to comment
Share on other sites

Yes , keep us informed how you get on - also what sort of shape the accumulators are in if you strip them. Accumulators are on my tick list so any shared knowledge is of interest.

 

Jim

 

 

 

Hi All,

 

I want to charge the accumulators (piston type x3) on my Saracen, instead of a charging bottle and because I don't want to rely on getting bottles charged, I've bought a bought an air gun charging stirrup pump (3000psi capability). It has a microbore hose with a 1/8 bsp female coupling. The fitting on the end of the accumulator appears to be a schrader valve (can anybody confirm this?). So effectively I'm looking for a 1/8 bsp male to female schader valve adaptor. Has anyone come across one or know of a workshop set up to make one?

 

Alternatively, what equipment/methods (without spending hundreds of pounds) do you use to charge the accumulators????

 

(P.S. I recognise that the use of nitrogen is best practice)

 

Thanks in anticipation

Link to comment
Share on other sites

Regarding accumulator stripping, the end retaining caps are blooming tight. A good vice and large stillsons are what I used to strip one. The end caps need prising out very carefully so as not to damage the seals, as not 100% sure if these are still available. a ggod length of wood is ideal to tap out the piston, again take care to not damage as it is made of brass.

 

 

This is the fluid end cap.

 

 

Another shot, other way up.

 

 

A pic of the air charging valve.

 

 

Same again, note seals 1 thick, 1 thin, not sure if it matters which way these are fitted, ie thick inside, and thin outside, or vice versa.

P130211_13.500003.JPG

P130211_13.510001.JPG

P130211_13.510002.JPG

P130211_13.510003.JPG

Link to comment
Share on other sites

A view of the piston, this has one thick seal, with a thin seal either side.

 

The seals go towards the fluid end of the cylinder.

Next a general shot of the cylinder and end retaining caps.

 

 

Rebuilding these, refitting and aquiring charging equipment is on my list of jobs too, as is resealing the fluid pump.

Cheers

Simon

P130211_13.500002.JPG

P130211_13.510005.JPG

Link to comment
Share on other sites

Just an addition to the above, make sure that all air pressure is released from the accumulator before stripping down, and release all fluid pressure before undoing pipes by working the steering wheel left and right until there is none left, brake pressure released by applying brakes frequently. These accumulators have high pressure at both ends and can be very dangerous!!!!

Cheers

Simon

Link to comment
Share on other sites

A few years ago, I took out one of the accumulators out of my Saladin and down to work to recharge.

Brain must have been switch off.

Turned on the regulator which was at 600 psi.

 

Oil at 600 psi hitting the cealing makes a mess. A big mess. Took days to clear up.

Lesson - empty the oil out first.

 

Andy

Link to comment
Share on other sites

  • 6 months later...

Finally got the gear together to recharge the accumulators. Was met by the sorry sould of bubble bubble bubble from the steering piston as the gas just washed through the line :( sad days. guess it is time to have the accumulator appart. Any Ideas on seal kits for these? mainly for the piston. Other than steering like a donkey she moves forwards backwards and stops now which is two directions and brakes further than i was.

Link to comment
Share on other sites

I can only offer opinions, no real factual knowledge.

 

If you can sacrifice some charging gas, I would try alternately charging and then running the engine to build some hydraulic pressure. The idea being to move the piston back and forth in the bore to see if it will reseal with some pressure on both sides.

 

I would have thought the seals would be cup type, but the parts manual list them as "washer, nonmetallic, syn rubber" with two different diameters listed 2.528" and 2.585" I have no idea what type of seals that describes.

 

I believe these accumulators are common to several vehicles, so I would guess Banister's and other vendors would have the rebuild parts.

 

Good Luck,

 

Bob

Link to comment
Share on other sites

If I remember correctly, these seals were both rubber and leather, fitted alternately. Many years ago since last stripped an accumulater to reseal. They are not an ideal sealing system, given the pressures involved, it is rather archaic, a double lip seal arrangement as in a hyd. ram would work better as there should always be oil present. A client of mine, some years ago, was a marine engineer and he had his Saracen accumulators reworked by a hydraulic specialists with modern types of seals. The pressurising in days when they were in army service was with Dry Air, we used to have our own plant for re-charging cylinders, to then take out and charge the vehicles. Nowadays, the normal gas to us is Nitrogen ( an oxygen free grade). Problems might have arisen if someone has charged with compressed air, with a high moisture content and rust could have developed in the accumulator bore.

Link to comment
Share on other sites

This post has answered one of my questions ...But i have another....

 

Can you use Copper pipes instead of the old steel ones on the braking/steering systems ?

 

Thanks

 

Ian

 

Ian,

 

Due to the high pressures, best to replace with steel again. Not safe to use copper in this instance.

 

regards, Richard

Link to comment
Share on other sites

This post has answered one of my questions ...But i have another....

 

Can you use Copper pipes instead of the old steel ones on the braking/steering systems ?

 

Thanks

 

Ian

 

 

Ian,

 

3/8 x 20 gauge copper has a pressure rating arround 30 psi higher than your hydrolic system is running at. I tried copper in my Saladin. Although it didnt fail, a got talking to a speialist in hydrolics who gave me pressure ratings for copper and steel pipes. So to be safe I bought a replacment steel pipe from Binister's.

 

Andy

Link to comment
Share on other sites

  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...