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Technical Area => Electrical Items => Topic started by: june2009 on March 24, 2009, 12:33:14 AM

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Title: MG Not Running
Post by: june2009 on March 24, 2009, 12:33:14 AM
Hey Art, it has been a while. I hope you are enjoying being stateside! This has been a tough winter and my MG is waking up a sleepy eye! Unfortunately it stopped running in October so I pushed it in the garage and there it sat. I thought I would work on it this winter but inside projects took priority.
When it stopped running it seemed like a carburetion issue as every time I would spray starter fluid it would start then sputter out. So, I rebuilt the carburetor. When I put it on it did the same thing (a shot of starter fluid) just once then nothing. I checked spark and I swear I did not see a spark at the coil or the plug. I putted around, pulled the cap and watched to see if there was a spark across the points and yes there was. A nice blue bright spark that looked to me like it was intermittently arching to ground! Is that possible? In hitting the web and reading my old emails it looks like a bad condenser could cause the car to start and putter out. This is a new condenser with maybe two hours of running time. If it could be a bad condenser, what would cause a condenser to burn out so quick?
When I reassembled the cap and checked spark I did have spark (which is why I say above I am sure there was no spark the first time I checked). I pulled a plug and they are all fouled up so I cleaned them and left them out. I will put it back together is a few hours of drying to see if it starts.
Anyway, any thoughts would help.
BTW I am looking for a clip for the distributor that holds the cap on (1975 MGB). I am using tie wraps to hold down one side. Any idea where I might be able to get something so odd?
Robert J. Ditta
Title: Re: MG Not Running
Post by: Art on March 24, 2009, 12:35:38 AM
Hi Bob,

Yes, still home and enjoying it, for the moment anyway.  This economy has only added to the tough winter we have all experienced.  I should be coming out to the Island soon.  I'll let you when I am and see if we can meet.

On to your B.  I have always held that if it feels like a fuel problem, it is probably electrical.  From the sound of things, that might be your case.  Distributor wear, deteriorated wires or a bad coil could give you similar symptoms as you are experiencing.  If it is a bad condenser, the reason might just be a poor QC on the line and one got by.  It's a cheap piece and bad ones do get through.  If you have an old condenser, put it back and see if the situation improves.  Same with the coil, primary lead and ground lead inside the distributor.  Check them for leakage or damage as they can be real problems if broken or shorted.  Check for wear or corrosion on the cam lobes as that effect the point gap (checking that as well).  Champion RN9YC plugs are about a buck apiece, so good to use and replace every year.  Cheap insurance that no corrosion has occurred while sitting in storage.

I once had a 73 Capri that at one point used to drive me crazy with this kind of problem.  Turns out that because it had this very long primary lead, every so often it came in contact with the exhaust manifold and shorted.  Felt just like the car ran out of gas.  Once I found what it was, it was an easy fix and never happened again, but I hate to tell you how many times I went into the carb looking for a blockage or other problem until I did. 

I would also strongly suggest considering a conversion to one of the electronic units.  I was just writing someone else with a PerTronix rig he lost the installation directions for them.  These kits cover a lot of ills, including some internal distributor wear, without other expense.  Also, if you use your car intermittently, they are sealed and do not wear, corrode or have to be cleaned and reset.  They also go in without modification to the distributor or other systems.  I have had one in my car for a few years now and am very happy with it.  I still carry a spare set of points and condenser in the tool kit to throw back in just in case.

Hope that helps.  hope to see you soon.

Best always,


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