Knuckling down
When the Landcrab went for its last MoT, I’d asked the tester to give no quarter when it came to checking over the front suspension. Since I bought the car in 2009, there’s always been a rattle at the front and even though the front ball joints have been checked many times, I live in constant fear of one failing. I’ve stripped, checked and regreased them a couple of years ago, but still the rattle persisted.
The MoT test verdict was that there was no play in the front suspension. So back at the lockup, I got the car up on stands and tried to work out where the noise was coming from. All control arms, track rod ends and bushes were in good condition. And then it dawned on me. The knuckle joints – which connect the Hydrolastic displacers to the top suspension arms – are hidden deep inside a heavy alloy casting on the ‘Crab. They are under tension when the car is stationary, so unless they were extremely worn, they wouldn’t show any movement under normal test procedures even if the tester could get a pry bar into them.
A quick look on that well known internet auction site and I’d secured a set of knuckles for a tenner (alright, plus hefty postage…). If I was only going to blame one for the rattles, I decided that would rule out changing all four. At first glance, it looked like a daunting task to strip out the front suspension. First job was to depressurise the Hydrolastic suspension system, which requires a special pump. Luckily, my brother had picked one up a few years ago – bought cheaply from the local rag small ads. We stripped it down to find it was full of Waxoyl which just goes to show how some people will always find a use for an obsolete tool. It was renovated and has proved invaluable, as the lockup houses two similarly suspended 1100/1300s (ADO16s) in addition to the Landcrab.
The Hydrolastic runs from
front to rear and the pressure is managed for each side via a Schrader-type valve located on the bulkhead. It’s a simple case of closing a valve on the pump, screwing on the connector to the valve on the car and then opening the valve on the pump to release the pressurized Hydrolastic fluid into the reservoir on the pump. With the suspension on full droop, I could reach in and feel the play in the knuckle and heard a familiar rattle where the shaft moved in displacer.
By releasing the top and bottom balljoints and supporting the hub on an axle stand and a ratchet strap, then undoing five large nuts, the suspension housing could be manoeuvred out with the top and bottom suspension arms still attached. The knuckle joint showed wear in several places. The ball was severely scored and the nylon cup it sits in mirrored this damage. It came apart easily and the new knuckle joint slid into place with a little grease and a tap from the hammer.
I also greased the shaft where it locates into the displacer in the hope that this will reduce, or even better, cure any chance of rattle, but only time will tell if this is the case. There was no drama in reassembly and everything slotted back together nicely. I even found time to remove some loose paint and surface rust on the inner wing to ward off any future corrosion problems before bolting the suspension housing back in place. Now, it’s just a small matter of attending to the other three corners and repressurising the suspension. More on that next month.
We stripped it down to find it was full of Waxoyl which just goes to show how some people will always find a use for an obsolete tool.