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flightlead404 flightlead404 is offline
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Join Date: May 2015
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Originally Posted by Rawknees'Turbo View Post
At some point, bubs, at soooommmmmeeeeee point (different than the "point" that you two choads are most familiar with! ).

Flight, the ignition delay shutoff action is not controlled by the yellow relay - it is controlled by the delay relay that is a small, silver metal box (replacements are black plastic) that is on the engine compartment relay panel next to the large box that is part of the rear window defrost circuit.
Yes, you're right. I've just been fooling with that thing, fingers moving faster than brain.

Originally Posted by Rawknees'Turbo View Post
As far as ignition shutting off momentarily between crank and run, and that having anything to do with the yellow relay, very interesting, as this is the first I've heard of that. I do know that if the yellow relay is working properly, it is part of the overboost circuit, it is part of the circuit that keeps the fuel pumps from running if air is not passing over the air metering arm/disc, and it allows the fuel pumps to energize very briefly (less than one second) when the key is turned to the run position (prior to actual starter movement).
I meant the delayed action relay not the yellow relay. Somehow I conflated the two in my reply.

To be clear, its the power shutting off to the switched buss momentarily as the key moves from the "crank" to the "run" position. I have confirmed this with a 'scope as well as practical observations. My key and wiring has never been messed with, so I can only assume its operating as normal. I need to retrace the wiring diagram, but it seemed to me that power would be interrupted to the CDI without the delayed action relay. With the MS it causes hot start problems. Given that some people are running w/o a delayed action relay maybe it doesn't make that much difference for CIS. Momentary loss of power to fuel pumps, WUR and so on would be inconsequential, but to ignition it might not be.

If you look at the drawing of the ignition key switch on the wiring diagram it actually makes sense. Of course, this is an electrical diagram not a mechanical diagram so it could actually be different in real life but....
Old 01-05-2017, 09:02 AM
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