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bob uk
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Posted From: brig-cache-4.server.ntli.net
Posted on Monday, 07 August, 2006 - 03:37:   Edit PostDelete PostView Post/Check IP

I was alarmed to hear a thump come from the rear suspension as I went over a road bump.

3 thumps later and I was heading for home at a steady 30 mph.

The L/H bump stop rubber had fallen off and landed on the trailing arm and was getting trapped between the arm and the chassis leg.

I briefly road tested the car with out the bump stop and the thump had gone.

The bolt which holds the bump stop to the chassis has broken off though rust. The chassis is not rusty so now I am going to drill out the broken bolt.

Does any one know what size the bolt is so I can re-tap the thread and weld a new bolt to the bump stop ?

Other wise I shall take a guess at 3/8 UNF. I do not want to touch the other side and have two broken bump stops.

(Message approved by david_gore)
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bob uk
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Posted From: brig-cache-4.server.ntli.net
Posted on Monday, 21 August, 2006 - 04:06:   Edit PostDelete PostView Post/Check IP

To answer my own question.

By reading tee one topics I found out that the bump stop rubbers are held by a 5/16 UNF thread.

Thank you Bill Coburn that saves me lots of time and I have a set of new 5/16 UNF taps and the BSI recommended drill size. I shall drill with a smaller dril first to ease the load on the black and Decker. Failing that I will cut the heal of the chassis mounting open and remove the captive welded nut re-new and weld back up and splodge under seal over the area and one would never know I had been in there.

It is always best to have a second cunning plan to repair something like this because drilling rusty bolts out can easily go wrong

Bump stops are important because the suspension could bottom out and bend something like the damper rod and posible even snap it, break the cup for the rear spring off the trailing arm, force the ram up ( stuff bad dreams are made of)which is why bump stops are checked at MOT time. Which is due November.

Also the stops that check the movement the other way are important I did see a Cortina Mk3 that broke the damper and driver kept driving one day the car went over a hump back bridge got daylight under the rear wheels and the road spring fell out jammed in the wheel arch and ripped the tyre off the rim. --Oh how I laughed.

I think it is remarkable of how many serious dangerous faults I have seen on cars and yet serious accidents are rare due to mechanical faults in the UK maybe things are different in OZ



(Message approved by david_gore)
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Bill Coburn
Moderator
Username: bill_coburn

Post Number: 722
Registered: 4-2003
Posted on Monday, 21 August, 2006 - 22:25:   Edit PostDelete PostView Post/Check IP

Bob

THank you for the mention - that was a while ago. Actually I came a gutza with that task in that I was fitting new shocks to the front and discovered the bashed up remnants of the front rebound rubber. Nearly died at the price of a replacement and bought local stuff which worked. Except that it was not needed. As you know the later shocks incorporated a limiter in their design which was carried on to the end of production. The upper arm dropping into a bloody great gutter at 50 mph must plunge down to the sub frame leaving a tissue paper clearance - quite amazing!

The worst thing I have seen at the rear of these cars is the bottom of the shock absorber punching a hole through the retaining cup. In repose the end of the shock was about 2 inches from the ground. That didn't stop the owner who went through another ditch and bent the shocker shaft a right angles which stopped the trailing arm dropping down and leaving the car on an angle. The shaft had to be cut with oxy to get the thing to pieces.