Hydrolastic problem

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boxofbits
Basic 850
Posts: 52
Joined: Tue Jun 28, 2011 5:00 pm

Hydrolastic problem

Post by boxofbits »

Hi all

I have a '66 Hydro Mk1. I have had problems raising the OSF suspension. It has a new knuckle joint, and I have tried another Displacer unit without success. The back rises okay, whilst the front barely moves. The NS is fine.

I have blown out the pipe with an air line and no obstructions. I then reassembled, slackened the front flexi pipe Union and bled fluid up to this point. Still does not lift. I have not 'evacuated' the system first as I am not using the old BMC style pump.

Any answers appreciated!

Regards

Kevin
Nevsmini
1275 Cooper S
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Re: Hydrolastic problem

Post by Nevsmini »

It sounds like the front displacer is seized!
Rubber Sprung
850 Super
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Re: Hydrolastic problem

Post by Rubber Sprung »

Could you have a seized top suspension arm ?
Dr S
1275 Cooper S
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Re: Hydrolastic problem

Post by Dr S »

When I put mine in refill the displacer through the hose before connecting up. You can get quite a bit of fluid in that way. I'm inclined to depressire mine an try and burp the front displacers as I wonder if they have an air bubble in them.
I've got a 69 Mini with a 1046, Cooper Head and a four on the floor.
boxofbits
Basic 850
Posts: 52
Joined: Tue Jun 28, 2011 5:00 pm

Re: Hydrolastic problem

Post by boxofbits »

Dr S wrote:When I put mine in refill the displacer through the hose before connecting up. You can get quite a bit of fluid in that way. I'm inclined to depressire mine an try and burp the front displacers as I wonder if they have an air bubble in them.
Dr S I think you're right. What I did in the end was jack up the front to take the weight off, let down the suspension on the OS, lift the front wheel a few times, then pump up with the weight still off. This got the Displacer working. I repeated this a few times.

At the moment I cannot get the ride heights correct as per manual ( 12 5/8" front / 13 1/8" rear +- 1/4") but if I repeat above enough I hope to get it closer. The best pump was the original which could purge the system of air first.

Do other members struggle with ride heights on Hydros and are they out from the manufacturer's settings?

Regards

Kevin
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LarryLebel
998 Cooper
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Location: North Vancouver BC

Re: Hydrolastic problem

Post by LarryLebel »

The strut could have been shortened at some time causing the disparity.
Dr S
1275 Cooper S
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Re: Hydrolastic problem

Post by Dr S »

Hi Box o bits,

In my chase for a level car a new old stock helper spring arrived this morning, feels stronger than I remember the ones on the car being.

I'll try and make some measurements against new and used shortly to see if that reveals anything.

Nick
I've got a 69 Mini with a 1046, Cooper Head and a four on the floor.
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Andrew1967
1275 Cooper S
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Re: Hydrolastic problem

Post by Andrew1967 »

Dr S wrote:Hi Box o bits,

In my chase for a level car a new old stock helper spring arrived this morning, feels stronger than I remember the ones on the car being.

I'll try and make some measurements against new and used shortly to see if that reveals anything.

Nick
Glad it arrived safely Nick 8-)
Dr S
1275 Cooper S
Posts: 976
Joined: Wed May 28, 2014 1:06 pm
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Re: Hydrolastic problem

Post by Dr S »

Cheers Andrew :-)
I've got a 69 Mini with a 1046, Cooper Head and a four on the floor.
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