Rotor arm - Cambridge
Hello everyone,

My Herald 13/60 has developed an occassional stutter or misfire.

I suspect electrics and am replacing leads, contact breakers, plugs, distributor cap, and ... rotor arm.

However, the rotor arm will not budge. I think it is just a push fit.

Any tips? Do I need to do some thing brutal like grab it with a pair of big pliers? I am worried about damaging the distributor shaft.

Thank you for your help.
Rotor arm - John S

Yes, the old Lucas rotor arms are 'just' a push fit. Normally they get loose raher than tight. A bit of judicious levering against the distributor body should move it.

Probably worth changing the condensor too. They are not the most reliable bit of kit, and are often the cause of misfires.


john S
Rotor arm - Peter D
This I think was a Lucas 25D distributor had a push on rotar arm but was a service item and required 4 drops of oil every 3000 miles onto a felt pad under the rotar arm. If this has not been done then the arm may have attached itself rather firmly. Assuming you do have a new one do not lever the old one off against the distributor body you mat bent the shaft. If it is really stuck cover the underneath workings and saw a slot in it and using a screwdriver blabe crack it open to remove. New points, condensor, rotar arm and cap may go a long way to clean up the ignition problem. Regards Peter
Rotor arm - Doc
You may find it easier if you remove the complete distributor (after carefully marking the timing position)
Rotor arm - Cliff Pope
Why not consider something like Luminition as you are replacing everything anyway? I have used it on several cars. It is totally reliable and you never have to do any more checking gaps, condensers, etc. It improves mpg slightly, reduces any tendency to pinking on unleaded petrol, and generally gives better running. The timing stays spot on indefinitely.
Rotor arm - John S

Yes, distributor lubrication for the cenrtifugal advance mechanism is often forgotten, as is the ned for a smear of grease on the cam to prevent excessive wear of the plastic 'caam follower' of the points. I have to say though, I think damage to the shaft is very unlikely - I did say 'judicious'levering, and I suspect the plastic rotor arm will crack before the shaft is damaged.


John S
Rotor arm - Cambridge
Managed to get it off by lots of wiggling...

Cleaned and gapped points and plugs. Replaced condensor, rotor arm, plug leads, and distributor cap.
Now runs very smoothly. No sign of the misfire on a short test run.

Thanks for the responses.

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