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MG Car Repair/1980 MGB ignition steering lock with ign switch assembly instructions


I just purchased a new steering lock and key/switch assembly for my 1980 MGB. I have rebuilt myself countless parts on the car but, always prefer instructions when available. The info is not included in my 75-80 MGB workshop manual by Bentley - which is a pretty good book. So,I need to properly dissemble the old and broken assy and install the new one. I have any/every tool that may be needed, I just don't have the knowledge I need to do the job right. Can you help or direct me where to go get this information? I will be grateful and thank you in advance for your assistance. Thank you.

Hi Bill.  So long as you have bought a complete replacement lock, with switch and shear bolts, this should be relatively easy.

The only difficult part is drilling out the two old shear bolts.

First you must drop the steering column, which is held by about 3 bolts (upwards).

Drill through the heads of the two shear bolts with a 1/8 (3mm) drill for a depth of about 1/2 an inch (12mm).  Then use a larger drill like 3/16 (5mm).  Then a bigger one until the countersunk heads come off on the drill bit.

Separate the two halves of the lock clamp and use pliers to remove the remains of the shear bolts.

From here on it is a straight replacement.  

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Barrie Jones


MG Sports Cars from 1949 to 1980 - Including MGB, MGBGT V8, TF1500, TF, TD and modern Midgets. I also specialise in SU carburettors, Lucas wiring, suspension, steering & brakes.


I have owned my 1955 TF1500 since 1966. Technical specialist for the TD and TF with the MG Car Club T Register. Also owned 20 MGBs and currently own an MGBGT V8. Written 3 books on MGs and produced a DVD on how to strip and rebuild the TD/TF gearbox.

MG Car Club.

Barrie's Notes on the 1953-55 MG TF (author). /=====/ Barrie's Notes on the MGB (author). /=====/ Barrie's Notes on the MGB GT V8 (author). /=====/ The Essential Buyer's Guide to the MG TD, TF and TF1500. (author)

M Phil, C Eng, BSc (Eng).

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