Rear springs Log Out | Topics | Search
Moderators | Register | Edit Profile

Australian RR Forums » Silver Shadow Series » Threads to 2015 » Rear springs « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

KC Saayman
Frequent User
Username: kc_saayman

Post Number: 89
Registered: 10-2004
Posted on Sunday, 19 April, 2009 - 09:44 pm:   Edit PostDelete PostView Post/Check IP

I want to check the rear springs ride height by depressurising the hydraulics to see if the car sits at the correct height on the springs.

My question is, do I perform this test with;

a) A full tank of fuel
b) A half tank of fuel
c) An empty tank

A full tank of 107 liters of fuel does make a difference.

Cheers

KC
Top of pagePrevious messageNext messageBottom of page Link to this message

Bill Coburn
Moderator
Username: bill_coburn

Post Number: 1107
Registered: 4-2003
Posted on Sunday, 19 April, 2009 - 10:28 pm:   Edit PostDelete PostView Post/Check IP

KC It is in the manual which is in the library. The correct specs involve an amount of fuel and weighting for passengers. What it doesn't tell you is to roll the car (having exhausted the two systems) back and forth some feet to let the back wheels assume their normal camber. A quick test without going to all this trouble is to depressurise, do the roll back and forth and the chrome strip on the bottom sill should point through the middle of hubcap on the rear wheel.
Top of pagePrevious messageNext messageBottom of page Link to this message

KC Saayman
Frequent User
Username: kc_saayman

Post Number: 90
Registered: 10-2004
Posted on Monday, 20 April, 2009 - 01:38 am:   Edit PostDelete PostView Post/Check IP

Thanks Bill. I just checked the manual, and all things considered I will be performing the test with a half tank of fuel.

Thanks!

KC
Top of pagePrevious messageNext messageBottom of page Link to this message

KC Saayman
Frequent User
Username: kc_saayman

Post Number: 91
Registered: 10-2004
Posted on Thursday, 23 April, 2009 - 11:24 pm:   Edit PostDelete PostView Post/Check IP

I have performed the test and have found the following results, and have a few concerns on which I would appreciate your opinions;

With the fuel tank half full the car sits perfectly level after depressurizing the hydraulics and pushing the car back and forth a few meters for the suspension to settle. So far, so good.

Then I filled the tank and loaded 100 kg into the boot. This obviously pushed the rear down quite a bit. I started the car and kept her on fast idle for about 5 minutes. Nothing, no lift. So I took her for a drive around the block, and when I returned she was nice and level. Why did the car not rise before I went for a drive?

I decided to check if the fast-rise solenoid works by sitting under the car while my wife performed all the tests like open and close the door and moving the gear selector from Park to Neutral and back. I could not hear or feel any click, so I am convinced the fast-rise does not work. Is this something that is easy to rectify?

I also did the brake pedal pump test after a 4-minute idle. Number 2 circuit light came on after 40 pumps, and number 1 came on after 60 pumps, so the accumulators seem to be OK. Yet, often when I start the car shortly after a run the number 2 light is on and remains on for about a mile. That seems to contradict the results of the pump test, not so?

I look forward to your comments. My conclusion is that everything seems to work, but perhaps not as efficiently as it should.

Kind regards

KC
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 309
Registered: 6-2006
Posted on Friday, 24 April, 2009 - 01:25 am:   Edit PostDelete PostView Post/Check IP

Hi KC,

The warning switch taking a minute to turn off could be the switch sticking inside.

Regarding the fast levelling valve, test for a feed with a test light.

If the fast levelling is not working, it would take a while for the suspension to work.
Top of pagePrevious messageNext messageBottom of page Link to this message

Richard Treacy
Grand Master
Username: richard_treacy

Post Number: 1674
Registered: 4-2003
Posted on Friday, 24 April, 2009 - 09:43 pm:   Edit PostDelete PostView Post/Check IP

It depends on the market and the year model under which conditions the solenoid clicks. For example, on our '72 T there is no interior lamp delay circuit. Even without the ignition switch inserted, on this car the solenoid clicks instantly whenever the driver's door is opened or closed. Of course, shifting it from Park disables it.

The solenoid function may simply be disconnected electrically. It may even be blanked off, ball bearings being inserted at the pipe unions, due to leaks.

If it leaks, the repair is simple: just replace two EPDM O-rings for a few cents rather than buying an expensive new or exchange unit.

Having said that, the two speed levelling is basically useless unless your passengers are Sumo wrestlers who climb in and out quickly. Witness that the SZ cars sit on their gas springs unlike the Silver Shadow. To rub it in, the response time on an SZ is about three minutes under all conditions, so they sit low for quite some time even unladen after being parked for a week or so. Intentionally, the SZ response time is very slow despite the constant need for hydraulic lifting by the struts. That a Silver Shadow only uses the hydraulics in heavy load situations, it is certainly a novelty to have fast levelling at all. With export Colonial (!!) springs, the stiffness makes the fast levelling almost completely irrelevant.

In the 1980s I replaced the solenoid on our T, stupidly buying an exchange unit due to leaks. My father thought that I was mad, naming the solenoid and dual-speed levelling a Rich Man’s Toy.

Take it easy. The fast levelling repair is only a job nice to do when doing something else in the same area.

RT.
Top of pagePrevious messageNext messageBottom of page Link to this message

KC Saayman
Frequent User
Username: kc_saayman

Post Number: 92
Registered: 10-2004
Posted on Tuesday, 05 May, 2009 - 04:54 am:   Edit PostDelete PostView Post/Check IP

Thank you very much for all the responses, I really appreciate it.

I have tested the fast leveling valve with a testing light, and it does get power when the transmission is in neutral. So at least I know the valve gets power.

You have set my mind at ease about the slow leveling, so I'm happy to leave it be. The car rides level with a load in the boot, so I'm happy, even if it takes a few minutes to reach the correct level.

One more question if I may, something that the manual is not clear about. On earlier cars you adjust the ride level by lengthening the little connecting rods, as I understand it. On later cars, such as mine, there is a groove in which the connecting rods mount, and to adjust you loosen the mount and slide it up or down.

If my assumption is correct, do you move it up to increase the height, and down to decrease the height? That is my understanding. Am I correct?

Kind regards

KC
Top of pagePrevious messageNext messageBottom of page Link to this message

Paul Yorke
Grand Master
Username: paul_yorke

Post Number: 319
Registered: 6-2006
Posted on Tuesday, 05 May, 2009 - 08:13 am:   Edit PostDelete PostView Post/Check IP

KC - you are indeed.

A small movement in the slot is quite a large movement at the wheel arch.