[Healeys] Tach heat sensitive?

[Alan Seigrist]

Tom -

I'm with greg on this one.  That little white wire has the most
current and variation in current going through it than any other wire
in the car.  That creates a situation where that wire will increase
resistance with so much use, and it sort of snowballs from there.  I
suspect that if you replace that wire, or at least replace the
terminals with good soldered connections to the terminals, you will
fix this problem.

Alan

On 8/19/11, Greg Mandas <gmandas at yahoo.com> wrote:
>
> Just a swag here, but my mechanic says my tach is running high because the
> wire the tach reads is old and therefore has higher resistance (?EE's?) He
> says he typically runs a new wire, therefore with lower resistance, o fix
> the problem, barring a complete harness replacement.
>
> That being said, and the fact a warmer wire has higher resistance, sounds
> like it should run higher at warmer temps.
>
> Sound Right?
>
> Greg
> 65BJ8
>
>>
>> On 8/18/11, Tom <ah3000me at gmail.com>
>> wrote:
>> > I've noticed that when I drive to work in the morning
>> when it's cool
>> > (50-60F), my tach shows about 2500 RPM at 65
>> MPH.  When I return home at
>> > night when it's warm (80+ F), my tach shows about 3000
>> RPM at 65 MPH.
>> >
>> > Any ideas about what's going on?
>> >
>> > thanks,
>> >
>> > Tom
>> > _______________________________________________
>
>

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