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TR6 Ignition Switch-73TR6

WJKB-TR6

Freshman Member
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The original fell apart with age and am using a replacement that does not have the same number of posts. Original switch is not of the pigtail type. I made a sketch of the original (attached) and am also including a sketch of the replacement. Comparing the two, do I have the wires correctly placed on the replacement switch? Engine starts and car runs on test drives; however, there is a drain on the battery amperage. I can not find a switch that matches the original.
 

Attachments

  • Original Ignition Switch_Sketch_2.jpg
    Original Ignition Switch_Sketch_2.jpg
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  • Replacement Ignition Switch_Sketch_2.jpg
    Replacement Ignition Switch_Sketch_2.jpg
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My suggestion is to use an ohmmeter or continuity checker to record the logic of the switch you have. Lucas made an awful lot of different switches, some of which look identical (but aren't). So just counting the number of pins doesn't necessarily identify what you have. There is also a non-zero chance of a new part being defective.

I don't think you want a brown wire on #5; instead you will probably need to insulate the second brown wire and leave it unused. But I could be mistaken. The earlier TR6 ignition switch shown in the manual has terminals 1,2,3,5 rather than 1,2,4,5.
 
Aloha WJKB. In 73 they added an 'anti-run-on' valve that got power when the IGN switch was in the OFF position and grounded when the oil pressure switch had pressure (typically for a few seconds until it bled off). I don't think your early-type switch has that connection, but if brown wire for the ARO valve got connected to the main brown terminal there could be a problem. Can you send a picture of the wiring at the back of the switch?

The anti-run-on valve is under the charcoal canister on the right side of the radiator. If its been on for a while it will be warm. If it is there, pull the wires off to disable and see it that helps.

Good luck - I left Hawaii (Hickam) in 2017 after retirement. Hope H1 traffic is better now with no visitors.

Jeff
 
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Thanks Randall and Jeff for your responses. Really appreciated!! I have modified the wire connections and connected BRN/Red to #5 as shown on the attached photos; however, not verified logic of the switch yet. The BRN/Red controls the ARO; not sure if it will work with this switch. I have not tried start up with the switch in this configuration at this time. I have installed a cut-off switch to protect the battery while sitting idle. I will inform you on its performance after first test.

Yes Jeff, things have changed since pandemic sanctions and "stay at home quarantines), extended to May 31. All visitors arriving have a mandatory 14 day quarantine to their lodging address. Government rules and enforcement very strict here. We just went thru Phase 1 relief Saturday, where populace may use parks and beaches for exercise only, no congregating. It's strange here in Hawaii seeing local people wearing masks and especially no hugging! Take care, Aloha and Mahalo! Willy
 

Attachments

  • Replacement Ignition Switch.jpg
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  • Ignition Switch Replacement (Modified)1.jpg
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  • Ignition Switch Replacement (Modified)2.jpg
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  • Replacement Switch Sketch (Modified).pdf
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Again, I'm almost certain that switch won't have the appropriate contact for the ARV (hot only when the ignition is off). You can either live without it, or add a relay to make it work.

If you leave it disconnected and it wants to run-on, learn to kill it with the clutch.
 
Again, I'm almost certain that switch won't have the appropriate contact for the ARV (hot only when the ignition is off). You can either live without it, or add a relay to make it work.

If you leave it disconnected and it wants to run-on, learn to kill it with the clutch.



Thanks again for your input. I will leave Brown/Red off and remove Brown (Thin) from main Brown (Heavy) terminal. This goes in line with Jeff, I believe. Will give it a try and also do logic. Mahalo (Thank You!)
 
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