Tach stops working as RPM's increase?

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Frey0357
Posts: 7
Joined: 30 Jan 2015, 10:45
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Tach stops working as RPM's increase?

Post by Frey0357 »

Hello everyone! I have been searching this fantastic site for months now and found the information available here to be invaluable! Thanks to everyone participating here!

I am very excited to have just purchased a 16' FM160B Sea Nymph with a 'Rude 60hp VRO, she really runs like a top (currently at 35MPH! 8) .

I have only had the opportunity to have her out one day so far, but when we were out cruising around the local lake I noticed that at low RPM's the tachometer works as expected, but when as I get higher in the RPM band the RPM's drop off and go to zero, boats runs fine.

Any thoughts or ideas where I should start? I am using the original tachometer on the console of the boat, which appears to be original to the 1990 Sea Nymph Fishing Machine (FM160B).

Thanks in advance!

Frey

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Skiffing
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Joined: 29 Dec 2014, 18:29
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Location: Northern Massachusetts

Tach stops working as RPM's increase?

Post by Skiffing »

Loose:

Sending wire
or
Ground wire

Or

Tach not calibtrated for engine.

You'll be able to get engine and control manuals online.

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DaleH
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Posts: 2466
Joined: 12 Dec 2014, 14:32
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Location: Eastern Mass

Tach stops working as RPM's increase?

Post by DaleH »

Right here ... from Teleflex Marine: https://www.jamestowndistributors.com/u ... ?docId=837

Frey0357
Posts: 7
Joined: 30 Jan 2015, 10:45
5

Tach stops working as RPM's increase?

Post by Frey0357 »

Thanks Skiffing and DaleH! I will check for loose connections, poor ground, and proper tach calibration. It may be a couple of weeks until I get back to the boat, but I will check into those and report back, my findings.

Frey

Frey0357
Posts: 7
Joined: 30 Jan 2015, 10:45
5

Tach stops working as RPM's increase?

Post by Frey0357 »

Been a while since I fixed the issue with my boat, but thought I should follow up and report back!

Thanks again Skiffing and Dale H., the issue was a weak ground connection under the console. Like many boats the wiring was a real mess under there and many of the connections were corroded and needed some simple cleaning. After cleaning the contacts and some crusing around on the lake again, problem solved!

Love this website! So many great ideas, plans and great folks to help out!

I am planning on a transom replacement this winter, so I will post that fun project when the time is right....until then keep cruising and fishing!

Frey

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