My 1969 911T is burning its points out.
Having replaced the coil,points and condenser, I'm thinking I may have the wrong condenser.
I've got a Bosch distributor which I think was a replacement for the original marelli.
What's the correct part number for he condensor !
Thank you
G
Points burning out
Moderators: hot66, impmad2000, Barry, Viv_Surby, Derek, Mike Usiskin
-
Strictly
- DDK slapper chatter
- Posts: 432
- Joined: Mon Jan 07, 2008 4:08 pm
- Location: Newquay, Cornwall
Re: Points burning out
Bad main engine earth strap also a possibility. I take it you dont have a cdi system? I thought cdi was from 69 onwards, I guess you were before the changeover?
-
Nine One One
- Put a fork in me, I'm done!
- Posts: 1635
- Joined: Fri Mar 01, 2013 11:45 am
- Location: Kernow - good old Cornwall
Re: Points burning out
Condenser will burn the points out, so too if its wired up to the coil incorrectly.
Light smear of grease on the metal rotor where the points foot touches?
Gap correct?
Have you got the right coil?
The coil may get warm when running, but if it gets scorching hot to the touch it's likely going bad in a hurry. The low resistance coil is intended for use with a ballasted ignition system (ignition resistor). Such low resistance would make the coil draw about double the normal current, which will cause it to run hot and possibly burn out, and/or may burn the contact points or melt the rubbing foot when running. Leaving the ignition switched on with engine not running (and points closed) for long periods of time may also burn out a coil.
One of the side effects of low coil resistance and high current is possible over heating of the contact points. This high current can burn contact points or melt the plastic rubbing foot on the contact points. Original contact points probably had a phenolic rubbing block which was very durable and heat resistant. Replacement points often have a plastic rubbing foot that may wear faster and may be susceptible to melting with excess heat. As the rubbing foot wears the points gap diminishes. As the plastic melts the points gap may go smaller or larger (usually smaller) depending on where it is melting. After readjusting a few times it may run out of adjustment range.
Light smear of grease on the metal rotor where the points foot touches?
Gap correct?
Have you got the right coil?
The coil may get warm when running, but if it gets scorching hot to the touch it's likely going bad in a hurry. The low resistance coil is intended for use with a ballasted ignition system (ignition resistor). Such low resistance would make the coil draw about double the normal current, which will cause it to run hot and possibly burn out, and/or may burn the contact points or melt the rubbing foot when running. Leaving the ignition switched on with engine not running (and points closed) for long periods of time may also burn out a coil.
One of the side effects of low coil resistance and high current is possible over heating of the contact points. This high current can burn contact points or melt the plastic rubbing foot on the contact points. Original contact points probably had a phenolic rubbing block which was very durable and heat resistant. Replacement points often have a plastic rubbing foot that may wear faster and may be susceptible to melting with excess heat. As the rubbing foot wears the points gap diminishes. As the plastic melts the points gap may go smaller or larger (usually smaller) depending on where it is melting. After readjusting a few times it may run out of adjustment range.