Tachometer Repair

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JimG
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Tachometer Repair

Post by JimG » Wed May 01, 2019 1:52 pm

Has anyone had a good experience getting a tach repaired? Would you recommend the shop?
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andyofcolumbusmerkur
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Re: Tachometer Repair

Post by andyofcolumbusmerkur » Wed May 01, 2019 8:42 pm

Check with the vendors here about a whole cluster or a parts cluster. But the cluster could be fine and the cable to blame.
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merkurdriver
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Re: Tachometer Repair

Post by merkurdriver » Sat May 04, 2019 1:38 am

Sometimes you can see a really obvious crack in the one soldier joint on the back of the tach once you have the tach out of the cluster. Usually the red wire. Its a 30 second fix once you have the whole thing apart. Anglin has some nice pics detailing it here:
viewtopic.php?t=10805&postdays=0&postorder=asc&start=30

taylor0987
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Re: Tachometer Repair

Post by taylor0987 » Mon May 06, 2019 10:22 am

Mine was intermittent. I didn't see any bad solder joints, so I just heated up all of them up quickly with the soldering iron. This resolved the issue.

my8950
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Re: Tachometer Repair

Post by my8950 » Mon May 06, 2019 2:13 pm

Curious about this....I've tried a few different clusters and my tach still reads about 80% of what it should be, roughly...
The tach moves slow and just doesn't seem "correct"...
I'm wondering if there are any other thoughts on this.
An idea I had was to overlay a new wire directly from the EEC to the input on the back of the cluster and see what that does.

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Re: Tachometer Repair

Post by Ed Lijewski » Mon May 06, 2019 4:35 pm

A thought.

You/your father now have a Scorpio I think. If that Scorp's tach seems to work okay, try swapping the coil from it into the XR and observe that tach's operation.

YMMV
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my8950
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Re: Tachometer Repair

Post by my8950 » Tue May 07, 2019 10:58 am

Ed Lijewski wrote:
Mon May 06, 2019 4:35 pm
A thought.

You/your father now have a Scorpio I think. If that Scorp's tach seems to work okay, try swapping the coil from it into the XR and observe that tach's operation.

YMMV
Ed, do you think think the V6 coil might make up for the 1/3 difference in the tach reading? Since the V6 has two more cylinders, it might make the 4 cylinder read higher?

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Re: Tachometer Repair

Post by Ed Lijewski » Tue May 07, 2019 11:42 am

Yup. :headbang

YMMV
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Re: Tachometer Repair

Post by my8950 » Tue May 07, 2019 12:04 pm

Ed Lijewski wrote:
Tue May 07, 2019 11:42 am
Yup. :headbang

YMMV
:D

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Re: Tachometer Repair

Post by Ed Lijewski » Tue May 07, 2019 1:39 pm

It's worth testing as the tach signal feeds out from one side of the two coil harness prongs, and as you've reflowed the gauge solder joints.

YMMV
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merkurdriver
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Re: Tachometer Repair

Post by merkurdriver » Tue May 07, 2019 2:07 pm

The coils are identical between both cars.
Last edited by merkurdriver on Tue May 07, 2019 2:14 pm, edited 1 time in total.

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merkurdriver
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Re: Tachometer Repair

Post by merkurdriver » Tue May 07, 2019 2:13 pm

merkurdriver wrote:
Tue May 07, 2019 2:07 pm
my8950 wrote:
Tue May 07, 2019 10:58 am
Ed Lijewski wrote:
Mon May 06, 2019 4:35 pm
A thought.

You/your father now have a Scorpio I think. If that Scorp's tach seems to work okay, try swapping the coil from it into the XR and observe that tach's operation.

YMMV
Ed, do you think think the V6 coil might make up for the 1/3 difference in the tach reading? Since the V6 has two more cylinders, it might make the 4 cylinder read higher?
The coil is the exact same part between the XR4Ti and the Scorpio. There is no difference between the V6 coil and the 4 cyl coil.

Worth swapping just to rule out the coil, but there is no way a "Scorpio coil" is going to make an XR tach read higher. ( As long as that XR has a 100% good coil in it ).

The cylinder number calibration is in the tach itself.

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Re: Tachometer Repair

Post by Ed Lijewski » Tue May 07, 2019 8:23 pm

Noah's post responding to mine, and my response to his, were sarcasm, Mike... :cheers

I know the coils are identical, hence the thought to swap to rule out the tach signal feed side of coil for my8950 as involved in his poor functioning tach. Yes, it's a remote possibility, but my8950 has been trying to get his tach working for some time (see MCA Facebook posts) after following all other recommendations for fixing it. The tach signal received by the tach has to be at spec for the tach to read rpms correctly. Someone may know how to assess that signal directly, but in the absence of anyone offering that info, trying the coil swap is a proxy for that.

BTW Mike, on MCA facebook yesterday there was a post with comments by a member who couldn't figure out how to mount and hang your Merkur Depot SS exhaust system, so he seemed unlikely to buy it although he was seriously considering it. You could answer his questions satisfactorily; no one else could.

YMMV
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John Brennan
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Re: Tachometer Repair

Post by John Brennan » Wed May 08, 2019 10:48 am

Ed Lijewski wrote:
Tue May 07, 2019 8:23 pm

BTW Mike, on MCA facebook yesterday there was a post with comments by a member who couldn't figure out how to mount and hang your Merkur Depot SS exhaust system, so he seemed unlikely to buy it although he was seriously considering it. You could answer his questions satisfactorily; no one else could.

YMMV
Thank you, Ed-- see new post, Merkur Depot Exhaust Fitment for the follow-up:

http://forums.merkurclub.net/forum/view ... 30&t=34508
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