Tach reads about 50%

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JimG
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Tach reads about 50%

Post by JimG » Wed Jul 25, 2018 4:40 pm

Tach started reading about 50% of what it should ie: 500 when should be 900-1000 and 2000 when sb 4000. Any thoughts ? How can I test the guage? Could it be the ignition module?
Jim Gosses
86 XR4TI, 165K, IC, RR, PBR Fronts, T-bird Rear Discs
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DAReese
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Re: Tach reads about 50%

Post by DAReese » Wed Jul 25, 2018 5:06 pm

Most likely it needs re-soldered.
David Reese

88 XR4Ti - mono white T5, someday to be bi wing
89 Scorpio - waiting on some parts before it hits the road again
88 XR4Ti - mono red C3, parts car
used to own 86 dark blue traded in on a min van, what was I thinking?

cmouta
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Re: Tach reads about 50%

Post by cmouta » Thu Jul 26, 2018 8:34 am

Yes, definitely resolder the board inside and it helps to use a really good, hot soldering iron.

See here:
http://forum.merkurclub.com/forum/viewt ... c&start=42

and here:
http://forum.merkurclub.com/forum/viewtopic.php?t=10560
Chris
1988 Mono Rosso Red Merkur XR4Ti

JimG
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Re: Tach reads about 50%

Post by JimG » Fri Aug 03, 2018 3:26 pm

Resolderered the board - now worse! Anyone have good tach that they want to sell? Am also considering aftermarket
Jim Gosses
86 XR4TI, 165K, IC, RR, PBR Fronts, T-bird Rear Discs
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my8950
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Re: Tach reads about 50%

Post by my8950 » Mon Aug 06, 2018 2:35 pm

JimG wrote:
Fri Aug 03, 2018 3:26 pm
Resolderered the board - now worse! Anyone have good tach that they want to sell? Am also considering aftermarket
Take it back apart and try to clean the potentiometer contacts.
Mark the current location and turn it a touch back and forth.
Also try some contact cleaner on it.

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