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MG MGB Technical - ELECTRONIC DISTR. CONVERSION

I replaced the distributor in my 79 B with what is reported to be a 45D unit with points and condensor. I have decided to change this points system to an electronic system due to the points twice collapsing. Ordered the kit only to find it does not fit. My question is two fold:

perhaps I have a 25-D distributor and what is the correct kit?

if indeed I do have the 45-D distributor what is the correct kit?

The LU-143 kit is not the one for my current distributor

Thanx in advance

cheers

Gary
gnhansen

Can't comment on the kit, but if something has fried your points twice then there is a problem as this should not happen. You might find the electronic ignition gets fried as well by the fault, and that will leave you stuck wherever it fails!! If I were you I'd sort the problem and then consider changing tho EI.

Iain

PS 25D and 45D have different dizzy caps. 25D has side entry or a rounded cap. The 45D is a more squred off cap. Have a look at http://www.moss-europe.co.uk/MossUK/ProductList.aspx?SubSubCategoryID=MGB_DS017F1
to see pictures.
I D Cameron

What brand electronic kit did you buy? Crane? pertronix? Luminition? What part does not fit? I run a 25D distributor with the Crane system and it is the physically largest system on the market. It IS a tight fit, but it has worked well for years. Describe the details about the problem you are having and maybe we can help!
Jeff Schlemmer

Thanx for the feedback.

I D Cameron: the points did not fry. the gap collaped created a bucking and carb backfire situation. So changing to electonic should stop that from happening. Looked at the website you posted and am starting to think perhaps I was sold a 25-D. As I am not doing the work on the car it is difficult for me to tell just what is bing done. In fact the car is some 250 miles south of here. Once it is fixed I need to drive it up to my home.

J Schlemmer: I belive the kit is pertronix. The part number was a LU-143. I suspect the LU prefix could be Lumination manufacture.????

Thanx again for your input. I will post as this progresses.

cheers

Gary :>{)
gnhansen

Gary
Try contacting Aaron at Coupers Classic cars in VT --they are very knowledgeable about Petronix and can tell if its the correct one for 45D dist. I am using a 25D in my 76B so its a different model --it works great.
Are you now in Westport just south of Plattsburgh ? Not too far away from me --Im near Malone.
All the best --Gil
Gil Price

Gil Price: Yes I am formerly of North Salem, NY and moved up to Westport just after the holidays. So much to do. Finally got around to getting the computer up. Give a shout when you can, 962-8515

Thanx for the tip

cheers

Gary :>{D
gnhansen

Gary,

I don't quite understand what is happening to your points when you say the gap collapses, but a set of points installed and adjusted correctly, should easily last between 6000 mile service with no further adjustment. They are generally very reliable. If yours are only a few miles old and causing problem then something is wrong with the ignition system. EI may or may not be effected by the same problem, but if it is then it could damage the EI, which is a lot more expensive to replace than points!! If it were me I'd still prefer to find the problem first if at all possible.

Hope you have the car going soon and can enjoy the summer!

Iain
I D Cameron

LU-143 is a Pertronix part number. The LU means Lucas. I have purchased Pertronix Ignitors from these folks several times. They're quick and reliable: http://www.vintageperformance.com/retrorockets/ignitor.htm . Click Car Applications and look for your particular MGB. I found that the LU-144 is correct for the 45D-4 Lucas distributor.


Charles Edwards

Oh, and the points close the gap shortly after fitting? That means that the lock-down screw is not doing its job. There should be a lock washer between the point assembly and the head of the lock-down screw. Sometimes the threads in either the distributor base plate or on the lock-down screw can become stripped. Examine them closely with a magnifying glass. If the base plate is stripped you may be able to re-thread to a slightly larger diameter lock-down screw. Be certain that it's no longer than the original screw. If the screw is stripped, then replace it.

Good luck.
Charles Edwards

Ok boys & girls, they got the LU-143 to work but now the altenator has packed up. The fun never ends. The
car is as dependable as this computer (lol).

Thanx to all who have contributed with your input. Redad on further as I ask on a new thread regarding altenators

cheers

Gary :>{D
gnhansen

Last detail regarding the conversion. After much ado, the LU-143 kit DID work. The reluctor is the same in the LU-143 as well as the LU-144. In the end the LU-143 took a bit more manuevering in its tight quarters . I do not if any other mods had to be performed accomodate the LU-143 vs LU-144 but it is working

thanx again

cheers

Gary :>{D
gnhansen

Got the call. The 79 MGB is ready for flight. All I need to do is go to Reader's Digest Auto Center and pick it up. After I complete the trip, I will post the results of the conversion perfromance. Many thanx to all who contributed to my cause. I plan to attend the Stowe, VT gathering in Sept. Hope to meet some of you there.

cheers

Gary :>{D





gnhansen

Lack of lube on the dizzy cam could also cause the points to close, eh?
Tom

Yes exactly Tom. This is a common problem on replacement points many of which are of dubious quality. I've had this many times in the past on other cars and the biggest problem seems to be the material that the moving contact cam is manufactured from. It just werrs down and closes the gap.

Gary already mentioned that the points are not burnt and that it is just the gap that's closing so there does not seem to be an ignition fault. Now that the electronic ign is fitted I don't think there will be any further problem.
Iain MacKintosh

This thread was discussed between 19/07/2005 and 01/08/2005

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