Hydrolastic bump stops rear

Post any technical questions or queries here.
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Andrew1967
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Re: Hydrolastic bump stops rear

Post by Andrew1967 »

Inaccessible once the tank is in Roger.

I use a ground down spanner to hold the helper spring whilst adding the nut inside the boot.

Not used to adjust the ride height, the system pressure does that
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Peter Laidler
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Re: Hydrolastic bump stops rear

Post by Peter Laidler »

`Ah, good questions Roger.
Last question first. There is absolutely no chance of getting to the helper spring upper nuts. seals etc etc once the tanks are in. UNLESS you cut out a small inspection hatch in the rear seat upright adjacent to the helper. But even if you do, there really ain't much you can do as with the tanks in the way there's really no room
No, the helper spring nuts cannot be used to adjust the ride height
So far as I recall, the nyloc-nut goes down until it meets the stop. A ledge/wider part that takes the outer and inner top-hat rubber seal. On top of the inner top hat is the steel washer. On mine, I added another flat neoprene washer between the top-hat seal and the steel washer. I just did it because I had a load of them! I also turned up the steel washers from stainless as is my thing.

As for holding the helper spring while you're putting the nut on top..... Another GOOD question if I've read it right!. Have a look at the top of the helper spring thread and you'll see that the end has two opposing flats....... see them......? Put the nut on until it's finger tight and these flats will (?) protrude through the top of the nut. You can use a small adjustable or a 3/16" AF open ended spanner to hold the shaft and tighten the nut down until it reaches its stop.

Have a great day at vehicle mechanics...

Just bumped into Andy's thread above. Both in agreement having both been there many times. Have a good afternoon too Andy
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Re: Hydrolastic bump stops rear

Post by apblake »

Just FYI for anyone reading this thread in the future: when I read this it wasn't clear to me whether the rear droop stops could be replaced with the radius arms in place or not (also with the hydro system pressurized). I can confirm that it is possible to do so as long as the bolts are installed backwards from the way the parts manual shows (in other words, if the head of the bolt that secures the rear droop stops is towards the front of the car).

If you want to replace the rear droop stops with the hydro system pressurized and with the radius arms in place, all you have to do is put the car on jack stands and then use a jack to crank the radius arm up into a loaded position (thereby relieving the pressure on the droop stop and creating a sufficient gap). Then you just need a skinny wrench to access the bolt head between the subframe. As long as you crank up the radius arm high enough there is enough clearance to remove the old bump stop and slide in a new one. It was actually not fiddly at all and pretty easy to do. Below are two photos to try to show the orientation of the bolt and what I'm talking about - 1 photo has the nut off and one has the nut on to try to make the orientation of the bolt clear.

Nut off:
IMG_4606_41.jpeg
Nut on:
IMG_4610_41.jpeg
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Spider
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Re: Hydrolastic bump stops rear

Post by Spider »

cheesebadger wrote: Fri Jun 18, 2021 2:12 pm Just to check my understanding...
Would it be fair to say the cone shaped rubber is a BUMP stop, and the flat shaped rubber discussed here would more correctly be called a DROOP stop?
The big one one on the Arm is a Bump Stop ;)

The smaller one on the Subframe is known as a Rebound Stop :)
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