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MG MGF Technical - Starter motor connection braid

I have been having some starter motor issues, which appear to have been poor connection, but I have a braided connection, which I believe is the connection from the alternator going back to the battery, via the (+)solenoid connection, which has just fallen apart over the years. It is about two inches long and then crimped onto the brown PVC wire. Where can I get hold of a new braid and how can you fit it as it is crimped on? Anyone have any ideas?
aj harris

Obviously the +ve needs to be in very good nick. But some of us have also rigged a -ve return from the alternator to the battery instead of using the two braided links and bodywork. It is massively more secure and prevents a lot of electrolytic corrosion on various elements, notably the coolant system components.
Charless

Hi Charles this sounds perfect, is there any instructions or advice anywhere about how to do this?
aj harris

The gist is c.3 yards of 32/02 wire or bigger with a constant current rating of about 50A or better. Solder a ring on one end, clean off any flux and bolt it to the alternator or proximal bit of cleaned engine. Grease it like a battery terminal. Then run the wire forwards with the underfloor pipe brackets up to the battery. Make another solder ring and bolt it with the -ve battery terminal.
This is an inexact science, even a wretchedly thin bit of wire is a big improvement on the OEM setup using two sections of braided earth strap and 4 corrosion prone connections to (and utilising) the car's bodywork. What you are trying to achieve is a preferential current return path between the two current sources - battery and alternator.
British cars with battery in the back and engine in the front rusted spectacularly quickly due to electrlytic corrosion and could suffer from poor starting as a much less important consequence (mini,MGB). The F has a huge capacity (conductive) coolant system as well, running the length of the car using several high valency different metals - recipe for disaster.
Contentiously, I also believe that ethylene glycol is preferable to OAT because it is much less conductive, just my opinion.
Charless

Hi Charles ok, I can give that a go! What about the +ve can I do the same thing and abandon the connection via the solenoid?
aj harris

I suppose so, if I understand you correctly - the solenoid will still need it's volts, but the +ve feed to the starter motor is the more critical element which must be as low loss as possible.
Charless

yes, Charles as far as I can see the main voltage is supplied by a large cable running directly from the battery so when the solenoid closes the power is direct to the starter motor. As this is a main connection, MGR have hocked the output from the alternator directly to this cable, so when the alternator is running you don't need the starter motor. Does this make sense?
aj harris

Yes, if all cable and particularly connections, are in decent condition. The +ve supply was always OK, just the return path which became vulnerable to wear and corrosion as the system components aged.
Charless

This thread was discussed between 04/11/2009 and 09/11/2009

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