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Thermal Relay Question

Old 01-05-2013, 08:52 AM
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Thermal Relay Question

I have not found this answer yet, and also researched my manual where they give "hints" but don't say it directly. On an early Z, 1970-71, why did cars with automatic transmissions have a thermal relay and cars with manual transmissions supposedly did not? If someone can answer that for me I would really appreciate it, and then ask the next question..... Have a good one....
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Old 01-05-2013, 09:58 AM
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Turn to "EC-11" in your manual (this is from the 72 FSM)............

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Old 01-05-2013, 10:30 AM
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Interesting!!! My manual (1970 English version) says that the reason for the thermal relay was related to de-acceleration purposes and also related to timing advance etc... and I guess I still don't understand the rationale of having it on cars with automatic transmissions and not manual, but I'll let the experts have at it on that one.... My problem is that my car has been altered... it has a five speed tranny in it, and if you do the research, a 1971 (August) could not come with a five speed.... but I do have that thermal relay, and it does affect to other things on the car.... first, is that it controls the engine cooling fan... or does it? Second, my car won't start and we are still trouble shooting that, but the red/black wire is still spliced in between the negative coil lead, and the distributor (spliced into the black wire).... and that red/black wire leads to the thermal relay.... and out of the thermal relay, is a black wire, that is supposed to lead to a thermal sending unit near the temperature sending unit and that is NOT there... it also shows a connection to the distributor and that is not there either.... I fear that this circuit, apparently unneeded is "open" which might be the variable as to why the car does not start... I am sure this was done two owners ago so I have no way of asking questions so I will keep on researching...

I do have one question for anybody that has tried this.... I ordered a new coil and ballast resistor for the car... as I am skeptical of what is one the car now... and will check out the switch (body work is dominating my time...) but can I hot wire this car like I have others over the years to try to start it? In other words, is there a reason I cannot run a wire from the positive post of the battery, to the positive side of the coil and check what comes out the other side of the coil and test the circuit all the way to the points? I know it can only be hooked up temporarily to start the car, but is this acceptable?

Thanks again for the article etc... will let you know....

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