Question about Mazda RX-7

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1985 Mazda RX-7 12a engine, I need the spark plug wiring hook up at the spark plug end diagram, picture or whatever Thanks Mike Widdop

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For the rotary engine used in the RX-7, each of the two rotorsin the engine is equipped with both a leading and a trailing spark plug. Theleading spark plug fires first, igniting the fuel/air mixture as inconventional engines; the trailing plug fires a moment later, igniting anyunburned mixture. This aids in more complete combustion and helps to reduceexhaust emissions.The 1981-85 model uses a four electrode spark plug which, due torotor housing modification, is the only type spark plug which can beused. 
On the RX-7, all of the ignition components for the leadingspark plugs have darker colored caps on their wires than the trailing sparkplug components. Even so, when replacing the spark plugs, it would be wise toremove and replace one plug at a time and reconnect its cable before moving onto the next plug. The spark plug holes can be identified by the letter andnumber codes adjacent to them. T1 means trailing spark plug,first rotor, L1 means leading spark plug, first rotor, etc.
It is advisable to only work on one spark plug at a time. Don'tstart by removing the plug wires all at once, because unless you number them,they may become mixed up. Take a minute before you begin and number the wireswith tape. The best location for numbering is near where the wires come out ofthe cap.
The procedure to replace the spark plug is as follows:--
1)Grasp the spark plug wire byits boot and twist to remove the boot and wire from the plug. Do not pull onthe wire itself, as this will ruin the wire.
2) Remove the spark plugusing the proper size deep-well socket. Turn the socket counterclockwise toremove the plug. Be sure the socket goes all the way onto the plug to avoid breakingthe plug, or rounding off its hexagonal wrenching surface. If the spark plug isequipped with a crushable gasket, make sure that this gasket is removed withthe plug.
Click this link for required parts to replace the spark plugs
click this link for how toremove the spark plug
click this link for which toolto use to remove spark plug
click this link for how to removecrushable gasket
3)Once the plug is out,inspect it for abnormal wear and note any problems. Check the plug against theaccompanying chart to determine engine condition. This is crucial since plugreadings are vital signs of engine condition.
4) Replace the spark plug. Installthe plug boot over the plug, so that the terminal inside the boot firmlyengages the end of the plug. Proceed to the next spark plug.
Thanks. keepupdated for any more can rate this solution and show yourappreciation.

Posted on Jul 04, 2010

  • Roy Mike Widdop Jul 04, 2010

    I still need a picture showing which wire from the distributer to the top or bottom of all four plugs

    T1, T2 etc

    Thanks \Mike Widdop

    I have a vision problem and it is hard to follow written directions

    Thank You



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