If this is your first visit, please click the Sign Up now button to begin the process of creating your account so you can begin posting on our forums! The Sign Up process will only take up about a minute of two of your time.

Follow us on Facebook Follow us on Twitter
Results 1 to 5 of 5
  1. #1
    Platinum Member Platinum Member ApachePete's Avatar
    Join Date
    Aug 2001
    Sarasota,FL & Saugatuck, MI

    Why do my tachs "float" ?

    With 500 EFI's, both tachs have started to waver and float when engine speed is constant. Gaffrigs in a 1999 382 Formula.

    Any ideas as to why? Ways to fix?


  2. #2
    Ginger or Mary Ann? Charter Member US1 Fountain's Avatar
    Join Date
    Oct 2000
    Lafayette, IN
    Mine did the same thing last yr. I was ready to buy a new tach. With the advise of a OSO member, I removed the wires on the back of the tach, cleaned them and reinstalled making sure they were tight. Fixed with absolute no more bounce or off wall readings. Maybe you could get as lucky.
    Some people are like Slinkies - Not really good for anything, but they
    bring a smile to your face when pushed down the stairs.

  3. #3
    Charter Member #30 Charter Member Scott's Avatar
    My Boats:
    PQ 38 Avenger
    Join Date
    Oct 2000
    Mine sank right to the bottom when they fell in

    Sorry had to
    I have Steps & Bubbles!

  4. #4
    Registered rjcardinal's Avatar
    My Boats:
    '99 27 Fountain Fever
    Join Date
    Jan 2001
    Baton Rouge, LA
    On my old truck and boat when the tach starts bouncing when it should be steady it has been arcing under the dist cap or some plug wires touching something and grounding out. Not enough for the engine to run bad just enough to fool the tach. I have noticed that if the wires are the culprit the bounce will be more noticable during periods of high humidity such as in rain or fog.

    Maybe its time for a tune up? If you do replace the wires make sure you route them in the same places so that they come into contact with as little as possible. On my boat the previous owner replaced the plug wires right before I bought the boat. It ran fine but I noticed the tach bounce a couple of months later. The guy just ran the plug wires in a hap-hazzard fashion with all of them touching each other. I seperated the wires and the tach bounce quit.


  5. #5
    Platinum Member Platinum Member mcollinstn's Avatar
    My Boats:
    1991 F311SR1
    Join Date
    Sep 2001
    Remove the tachs. If you can get the "guts" out of the housing then do so. Take a Q-tip and put contact cleaner on the selector switch (for 4-6-8-outboard selection) then move it back and forth a bunch of times.

    When done, dry the contacts off and spray CRC on the contacts and put the switch in the proper position. Won't hurt at this point to spray a little red battery terminal wax on the switch.

    Put her back together and rock on.

    IF you CAN't get the housing apart and get the guts out, then spray a little WD40 around the hole the selector sticks out of )or look for a drain hole closeby to spray it into). Then do the back and forth thing with the selector.

    Of all the floating tachs I've seen, if you can get to the contacts for that selector, then you've got the problem licked.
    I see London, I see France...

Similar Threads

  1. "747 Say Goodbye" "Big Scorpion" "Climax"
    By bobo1 in forum OPA/The Jersey Boyz
    Replies: 0
    Last Post: 04-23-2008, 07:36 PM
  2. OUTDRIVE "B"ring "O"ut "A"nother "T"housand
    By electrical1 in forum General Q & A
    Replies: 11
    Last Post: 11-09-2006, 08:51 AM
  3. """Thinking""" about selling my 2500HD CC, Duramax...
    By [email protected] in forum Trucks, Trailers and Transportation
    Replies: 14
    Last Post: 10-13-2006, 09:11 AM
  4. "Fastest" or close "27 Activator or equal??" (keep in mind, in rough water)
    By ActiveFun in forum General Boating Discussion
    Replies: 0
    Last Post: 04-26-2004, 09:42 PM
  5. "Speek Kills" vs "King of Thunderboat Row" vs. "Blue Thunder" ?
    By mikesufka in forum General Boating Discussion
    Replies: 8
    Last Post: 12-26-2002, 11:23 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
All times are GMT -5. The time now is 05:02 PM.
Powered by vBulletin® Version 4.2.0
Copyright © 2016 vBulletin Solutions, Inc. All rights reserved.
Search Engine Optimization by vBSEO 3.6.1
Original Poster In Postbit provided by Original Poster In Postbit v1.0.0 (Free) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Copyright 2011 OffShoreOnly. All rights reserved.