| Author | Message | ||
     Richard Treacy Grand Master Username: richard_treacy Post Number: 415 Registered: 4-2003 |
The manuals go into all sorts of fancy procedures to check standing height, but never give a specification for a vehicle's correct height with a pressurised system. First is to check the standing height with no pressure to see if the steel springs are OK. That is not usually necessary: it is specified in later manuals, but not the earlier ones. They specify a correct vehicle loading (full tank of fuel, all tools and spare tyre in place), tell you how to fiddle around a bit, then finally specify a pressure setting at the height control valve once everything else has checked out. I have always felt that you really need an instant measure which is simple to take as a quick diagnostic. The pressure method is very sensitive to having the vehicle accurately loaded during setting up, and that’s a bit hit and miss anyhow. A first inspection of a prospective purchase is aided by an instant check. When everything seems fine, or after another unrelated job upsets the height control linkage, you can successfully adjust the standing height if necessary as outlined below. It is not load sensitive, and will always give a proper result. Furthermore, you do not need to open up the system, you don't need a special pressure gauge, and no fluid or bleeding is required. Last night I changed the rear antiroll bar rubbers. That meant removing the height control linkage (actually a small torsion bar on all cars from 1987), and readjusting it after refitting. For all standard-bodied SZ cars, proceed as follows. Cars before 20,000 differ from this method only in that they have two height control valves instead of one, so both will need checking and adjusting as necessary. Run the motor so that the hydraulic systems are fully pressurised and turn it off. Measure from the centre lip of the rear mudguard (ie directly above the tyre) to the wheel centre. That should be 400mm +/-5, or 15 3/4" +/- 1/4". Adjustment is simple. Don't jack the car. Lie on a rug, and you can easily reach the clamp (toward the centre of the antiroll bar) to adjust it with a spanner by loosening the U-bolt. Mark the starting position with white paint first. With the pressure up, adjust the clamp maximum 1mm at a time and wait a minute for the level to stabilise. Turning the top of the clamp towards the front of the car raises the standing height. It is very sensitive. NEVER try to lever the valve end of the link or its lever as it will break very easily. For pre-20,000 cars, the sides may be adjusted individually at the actuator rods themselves. These types (there are two variants) do not have the U-bolt arrangement toward the centre of the antiroll bar. Here is a simple but useful mod to improve the slotted end fitting which engages the height control valve of all post-20,000 series SZcars.. Buy a small piece of thin 13mm inside diameter aluminium tubing from your tool supplier, and cut a 15mm length to form a sleeve. Remove the height control linkage, clean it, apply Loctite 638 to the inside of the sleeve, and simply slide it over the slotted fitting which connects the height control valve. This slotted fitting is very flimsy and is easily broken. Allow to set for 20 minutes, repack it with grease, and replace the original rubber grease retainer cap. Pop it back onto the car and adjust the height as described above. This is a great improvement for grease retention, rattle, and vastly improved strength. | ||
| Larry Halpert Frequent User Username: larry_halpert Post Number: 30 Registered: 9-2003 |
Did you take any photos of your mod & parts locations? Larry tbird@consultant.com | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 419 Registered: 4-2003 |
Hi Larry: I thought that you may be interested, having already corrected your height settings this way. As it's all installed, I have a few snaps and a sketch to clarify the mod. By the way, it makes fitting the lever far easier. The ball end at the height control valve can no longer slide out of the slot as you manoevre the lever. RT. Installed:  Installed, with the sealing boot lifted; you can see the sleeve:  A sleeve ready to slide on after smoothing the end:  Sketch of the lever at the height control valve end:  Component Layout:  | ||
| Edward Mckinley Experienced User Username: ed_mckinley Post Number: 46 Registered: 2-2013 |
Hello all, I am chasing an issue with the height control on my Corniche (1989). after sitting through our Chicago winter I noticed a small amount of HSMO under one of the rear leveling rams (10 drops or so). After starting, she raised her sagging bottom and proceeded as normal. However, what I noticed is that when the rear is sagging to its lowest point the car raises properly about 2 1/2", but when the rear has only sagged an inch or so, no leveling occurs. I suspected air in the line and bled the system and the car leveled. Since I did get some air out of the lines I changed the only two hydraulic hoses that have not already been changed - the supply lines from the reservoir to the pumps. Bled the system afterward and now the car will not raise at all. I am now suspecting the height control itself. When I disconnect the torsion bar and turn the valve manually, nothing happens. Am I on the right track? |
