Eye-bolt pin & bushes

Rebuilding, adjusting, maintaining & alternatives
Post Reply
User avatar
LaughingBoy
.
Posts: 8
Joined: 6 years ago

Eye-bolt pin & bushes

Post by LaughingBoy »

Decided I'd dismantle the front suspension to try and get rid of an annoying squeak. I have greased the eye-bolt bushes and pivot pin and spigot cup and re-assembled everything. It got me wondering how the bushes and pin absorb the rotational forces from the arms. I found this old post from Custard :

"The intention is not for the arm to rotate on the cup, but for the Torsion bar and cup to rotate so it is the pin going throught the eyebolt that rotates."

My question is how and by what is the pin 'gripped' to make it rotate? I think the spigot cup rotates freely in the recess of the rear arm so that would not grip it ...



User avatar
Mecanglais
Formally known as chesney
France
Posts: 2155
Joined: 9 years ago
Location: France

Contribution Stars

Re: Eye-bolt pin & bushes

Post by Mecanglais »

The cup should be an interface fit with the rear suspension arm. It shouldn't turn in the arm.
Provided the bushes and the pin are in good condition, and that the pin is firmly tightened to the cup, the suspension movement should be taken by the rotation of the pin rather than the cup rotating in the arm.
Maybe a little primative, but this is early independent suspension, most of the stuff earlier than this was effectively a girder with cart springs!



User avatar
Custard
.
Ireland
Posts: 2415
Joined: 8 years ago
Location: Blackpool

Contribution Stars

Re: Eye-bolt pin & bushes

Post by Custard »

You also have to remember that once tightened the other end of the pin is tight to he front arm and both arms are fastened together.

So the pin will want to rotate with the arms rather than stay still.

Having dismantled a fair few of them I think what actually happens after a while in most cases is the arm pin and bush start moving in the eyebolt.

Its a shame the eyebolt wasn't larger as then there would be space to have a bush with a steel liner.

If you imagine the bottom arms and the tie bar as a single item you get a triangular plate which is what a lot of cars had for many years just with a coil spring above them instead of a torsion bar.

Then the next step is to just use the outer rim of the plate with a smaller coil spring round a damper and you have the JLH set up for a Morris Minor.

Its an early version as stated , but relatively light weight and low bulk. Unfortunately its just not that tuneable as you cant move the mounting points around easily.

Sean.



User avatar
LaughingBoy
.
Posts: 8
Joined: 6 years ago

Re: Eye-bolt pin & bushes

Post by LaughingBoy »

Thank you Mecanglais for the concise and helpful reply. I did use some grease (as opposed to copper ease) on the outer curved face of the spigot cup - is that likely to make it slip? (I just hope the interference fit in the rear arm still works!)

Also thank you Sean for your further insight. I have poly bushes and I suspect these will partially rotate in the eye-bolt whereas I think the original rubber bushes are designed to flex. As regards bushes with metal sleeves I have heard of people fitting Metalastic eybolt bushes with excellent results - see here

https://www.mmoc.org.uk/Messageboard/vi ... 4761fd4f61



Post Reply