rotor arm problems

[carmadme69]

having had several break downs in life with cars . i have been having problems with the new rotor arms, when running in traffic fairly hot they give up without warnning has anyone else found this problem, i have got hold of sum old ones now that seem to be fine, had old one in and done 500miles no problems but new type seem to give up after 150/200 miles

[dogoncrazy]

Re: rotor arm problems

Where the problem ones manufactured by 'Intermotor' by any chance?

[hallbenjaminj]

Re: rotor arm problems

Ive had this problem as well (1275 a series), usually a rest and cool down sorted the problem but last time it was a complete failure. RAC turned up with a replacement rotor arm, had a strange lump on the oposite side to the contact but touch wood fine ever since, unfortunately I dont know the make of it, i'll take a look and see if it has any marks on it when i get a moment!

[h_m_cumming]

Re: rotor arm problems

What's a rotor arm?
Seriously, I changed to Lumenition when I had the 1800 in my Marlin and it ran faultlessly. The Fiat I have now is also Fiats own electronics and again runs well. Go electronic.

[cdow]

Re: rotor arm problems

Yep, I had Magnatronic on my B and it was superb, not too expensive either

http://www.mgocaccessories.co.uk/acatalog/MGOC_Accessories__Ignition_35.html

[b_caswell]

Re: rotor arm problems

Distibutor Doctor has just introduced new quality rotor arms (in red body)
www.distributordoctor.com.

[carmadme69]

Re: rotor arm problems

tell me changing to electronic ignition dont you still use the rotor arm as somthing has to send the spark to the plug????

[andy4]

Re: rotor arm problems

Yep a magnatronix still has the rotor arm, the points and condensor get replaced by the hall effect sensor and the magnetic disk. I have a magnetronix on my old rover and it is the best money I have spent. For my Marlin I have just fitted a cheap alternative - http://simonbbc.com/automotiveshop/electronic-conversion-kit-45d-distributors-newest-profile-p-17.html - not sure if it is going to be any good, but worth a try for the money - I will report on how reliable it is - the red module version is an improved one, they also sell a "blue" version which some people have reported problems with. He also sells them on e-bay. In the cheap setup the magnets are in a special rotor arm, unlike the magnetronix which has a seperate disc and a normal rotor arm.

[carmadme69]

Re: rotor arm problems

i had a electronic ignition on my 1275 engine but it too broke down as the rotor arm was made of this cheap plastic , have found info from DISTRIBUTOR DOCTOR on this same problem he is making new ones in a different plastic/bakerlite

[tony.branson76]

Re: rotor arm problems

I have been suffering from this problem for 2 years and on this year's Ilkley trial I at least partly solved the problem by fitting an old rotor arm. The symptoms are purely related to under-bonnet temperature. I have fitted a thermometer in the engine compartment and at about 35 degrees the engine starts to misfire on high throttle opening, it gets progressively worse until it will just trickle along on idle and eventually dies. It won't start until cooled down. I changed everything and nothing seemed to help until I put the old rotor arm in and I had my old car back again. I will be patronising the distributor doctor as soon as he has a rotor arm for the 45D.

[donsayers]

Re: rotor arm problems

I heard tell that there was a faulty batch of "new" rotor arms that were made with too much carbon black in them and they became conductive at elevated temperatures. They may have been pattern parts made in China. I think the source of the story was an MGB forum. I cannot find it now.

I had no luck with "Luminition" again there are those who swear by it and those that swear at it. Mine would cut out for no reason and then start again without me having done anything. The last straw was when it finally gave up and stranded me mid M1.

Now on points and no trouble.

[carmadme69]

Re: rotor arm problems

hi Tony have solved the problem with a old lucas roror arm from auto jumble , it has a number on to lucas 54422803 only 50p well worth keeping an eye open to save trouble good luck

[lizbillings]

Re: rotor arm problems

A friend had this problem with rotor arms when we went to France 3 years ago. He has an MGB and went through 5 in a couple of days!

[stevejgreen]

Re: rotor arm problems

More on rotor arms.
I had some starting issues, on examination the rotor arm had been hitting the cap contacts. The rotor arm was loose on the dizzy shaft even with the spring clip in place.
New ones fitted and all ok now.