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Author Topic: No ignition  (Read 1798 times)

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june2016

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  • Posts: 4
No ignition
« on: May 09, 2016, 08:32:21 PM »
Before I took my 'B' off the jacks for the driving season, I pulled the radiator and had it cleaned and  pressure checked. Reinstalled radiator, new hoses and thermostat, put in new spark plugs, antifreeze and oil change. Recharged the battery hooked it up and turned the key ... nothing not a sound.

I immediately checked my battery connections, good, and then I checked the fuses, changed them but still nothing. The lights work, horn and directional so juice is getting through the vehicle but nothing else.

What do I need to look at now ?

Jeff Sikora
Orland Hills, Illinois

Art

  • chfwrench
  • AMGBA Club Tech Staff
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  • Posts: 246
  • Memberhsip Number (if known):: 91-10014
  • MG information: '73 red B roadster
Re: No ignition
« Reply #1 on: May 09, 2016, 08:34:23 PM »
A:   Always fun when Lucas electricals live up to their reputation.  Couple of things  to check first:

- Check the starter solenoid wires. You can't see them easily if you have the plastic weather cover on your starter, but they can come loose or get corroded. Take the cover off.  The solenoid is on the bottom of the starter and there should be a single push-on blade connector facing down (the usual suspect) at the bottom of it, as well as bolted connectors for the positive battery cable, ignition power wire and a direct connection to the starter (usually a solid copper bar). Make sure all are clean and tight and try again. 

- If that's good and the starter is still not working, wear a heavy glove and use an old screwdriver to short across the 2 main cable poles on the solenoid.  The starter should then engage.  If not, the starter itself may be at fault. 

- If it does, it could be the solenoid, but replacing it is as much work as replacing the whole starter. I would look to get a complete rebuilt or new replacement.  About $170 new outright sale (no core return) from V-B (P/N 8-153) or about the same from Moss.  A local rebuilder may be cheaper, but the new unit will have better insulation and performance.  To check the solenoid, pull the blade connector off the solenoid and put a meter set to read 12VDC between the connector and a ground to the chassis. Do not hook it to the blade on the solenoid.  In the line from Ghostbuster, that would be bad. Get someone to turn the key an see if you get juice when they do. If you do see current, check the connectors again and try it once more (without the meter).  Still no starter, I'd plan to replace it 

- If the starter engages when the connections are shorted and there is no power to the connector from the ignition switch, check the back side of the keyed ignition switch.  The electro-mechanical drum switch can wear or come loose and only make partial connections.  The lights and accessories are first position as you turn the key, so tend to work even if there is damage.  If it is broken or cannot be tightened, make sure you order the replacement with the same connectors as the original. There are at least 2 different types (bullet connectors or single plug connector). If no issue there, go back to the solenoid

Other than these, there are at least the 2 long wires from the ignition switch in the interior that might have corroded, cracked insulation or proven tasty to Mickey and Minnie over the winter.  Those you'll have to trace and check using a wiring diagram and meter individually. 

I hope that helps you.  Good luck and let me know what you find.  Any further questions, just ask. 

Safety Fast!
Art Isaacs
Art Isaacs
AMGBA Tech Staff
chfwrench@aol.com


 

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