Bad reading on the tachometer...

Lake_BumLake_Bum Member Posts: 1,143 ✭✭✭✭
in General Boating Discussions
My boat is a 2000 Captiva 232, with the 350mag and Bravo lll outdrive.  I had very irregular readings on the tach when I test drove it.  I ended up buying it, and had to winterize it once I got home, so it's tucked away for the winter now! I was getting readings off the charts according the the gauge, as in buried above 6000 rpm's even at cruising speeds, and from my speeds, and sounds on the motor I would guess it at 2800 "actual".    
Any clues as to how to address that issue, once spring rolls around?  The readings were normal at idle, then would be all over once on plane....... 
2000 Captiva 232 
· Share on Facebook

Comments

  • Handymans342Handymans342 Member Posts: 10,375 ✭✭✭✭✭
    Replace tach
    · Share on Facebook
  • Lake_BumLake_Bum Member Posts: 1,143 ✭✭✭✭
    Handymans342 said:
    Replace tach
    Hahahahaha  I don't know why I found that so funny, but it was!  Sometimes things ARE that simple  B)
    2000 Captiva 232 
    · Share on Facebook
  • frenchshipfrenchship Member Posts: 1,079 ✭✭✭
    Is it a Faria gauge?
    · Share on Facebook
  • Lake_BumLake_Bum Member Posts: 1,143 ✭✭✭✭
    frenchship said:
    Is it a Faria gauge?
    I believe so. I know it is a factory gauge, but it is currently tucked in until the snowstorm subsides.....
    I'll probably just remove/replace it when I find the time to install my fishfinder this winter. I was just hoping for a little insight from someone that has encountered the same problem with their tach. 
    2000 Captiva 232 
    · Share on Facebook
  • LaReaLaRea Member, Moderator Posts: 8,077 mod
    It's one of the most common problems.  In some cases, people have found grounding or wiring issues that caused it, but that's rare.  

    You could also look at using VesselView Mobile to see engine RPM (and other data).  It's a bluetooth transmitter that plugs into your engine and uses your cell phone or tablet to display real-time data.  $275 from Mercury.  
    · Share on Facebook
  • IanIan Member Posts: 3,075 ✭✭✭✭✭
    Mine do that too, sometimes just a tap will fix, other times the demons leave the gauge themselves and all is well until next time. From many other comments in the forum it seems to be a Faria trait.

    Regards,

    Ian

    The Third “B”

    Ravena Coeymans Yacht Club

    https://www.rcyachtclub.com/

    · Share on Facebook
  • StodgeStodge Member Posts: 2,738 ✭✭✭✭
    Some tachs have a switch on the back for 6 cylinder and 8 cylinder.  Might be worth a look to see if that switch is there and out of place.

    A smartcraft tach would be nice, but I don't think Mercruisers had smartcraft before 2002.

    Bad ground is always a likely cause.  If you have access to an automotive diag tool with a tach (I have one that looks like a VOM but has tach and dwell), might want to try reading the RPM with it using the wires at the gauge.

    Good luck.


    2002 FV 342 on Lake St. Clair - Past Commodore SHC - Vessel Examiner USCGAUX

    · Share on Facebook
  • Handymans342Handymans342 Member Posts: 10,375 ✭✭✭✭✭
    Stodge said:
    Some tachs have a switch on the back for 6 cylinder and 8 cylinder.  Might be worth a look to see if that switch is there and out of place.

    A smartcraft tach would be nice, but I don't think Mercruisers had smartcraft before 2002.

    Bad ground is always a likely cause.  If you have access to an automotive diag tool with a tach (I have one that looks like a VOM but has tach and dwell), might want to try reading the RPM with it using the wires at the gauge.

    Good luck.


    Stodge, what do you use if it is a 4 Cyl diesel? LOL
    · Share on Facebook
  • StodgeStodge Member Posts: 2,738 ✭✭✭✭
    A metronome..... :)

    2002 FV 342 on Lake St. Clair - Past Commodore SHC - Vessel Examiner USCGAUX

    · Share on Facebook
  • zaverin1zaverin1 Member Posts: 1,672 ✭✭✭
    Maybe a 4cyl setting and a gage with a ✊ mode 
    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    Faria gets 125 a tach for repair plus shipping.that does not mean it will a corrected reading but it looks good . its on there  Web sight Faria beebe.com.
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    Handy it's 4,6,8 but only for us gasser.you smokey boats don't have ignition they just run forever . 
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
  • Handymans342Handymans342 Member Posts: 10,375 ✭✭✭✭✭
    reneechris14 said:
    Handy it's 4,6,8 but only for us gasser.you smokey boats don't have ignition they just run forever . 
    You are smoking too much smoke
    · Share on Facebook
  • zaverin1zaverin1 Member Posts: 1,672 ✭✭✭
    ✊ it's not smoke anymore
    it's called clear
    the real truth oil
    · Share on Facebook
  • Lake_BumLake_Bum Member Posts: 1,143 ✭✭✭✭
    Thanks for the input guys!  B)
    2000 Captiva 232 
    · Share on Facebook
  • pault1216pault1216 Member Posts: 206 ✭✭✭
    Corrected mine by cycling 4-6-8 switch several times and tightening/cleaning wire connections. This worked on 2 of my boats. Good luck.
    · Share on Facebook
  • 69fastback69fastback Member Posts: 951 ✭✭✭
    My tach on my 232 is crazy too. It's just all over the place. Maybe I'll fix it this year. 
    · Share on Facebook
  • SeaHareSeaHare Member Posts: 194 ✭✭✭
    mine are all over too.. faria gauges. cycling 4-6-8 helped. Also a good whack with my pointer finger knuckle puts it back in place
    01 FV 310, 5.7s carbed, B3s
    · Share on Facebook
  • rasburyrasbury Member Posts: 9,000 ✭✭✭✭✭
    I don't worry about it to much....I just go by the sound anyway and the feel of the boat. If I had twins I'd think it be more important.
    · Share on Facebook
  • Lake_BumLake_Bum Member Posts: 1,143 ✭✭✭✭
    rasbury said:
    I don't worry about it to much....I just go by the sound anyway and the feel of the boat. If I had twins I'd think it be more important.
    I definitely pay attention to the sound as well, but I am OCD with anything that isn't working perfectly on my boats.  If I ignore one thing, that leads to another  B)
    2000 Captiva 232 
    · Share on Facebook
  • SeaHareSeaHare Member Posts: 194 ✭✭✭
    Actually with twins, you have the sync gauge, which has always been accurate. Between the two tachs, one of them is always right, then just sync the engines... with experience, sound is all you need
    01 FV 310, 5.7s carbed, B3s
    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    I like all things to work so I will pay,and hope they last for a while.or a VV7 maybe next.
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
  • StodgeStodge Member Posts: 2,738 ✭✭✭✭
    I only kept the sync and the multi-gauges (because they show fuel).


    2002 FV 342 on Lake St. Clair - Past Commodore SHC - Vessel Examiner USCGAUX

    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    Nice and clean,good work
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    Sent out both tachs and sync gauge in Nov. and they sent new gauges back today.That's assome but the tachs will be zero hours.well I guess I will know how many hours I put on the boat.+300 port +296 starboard.
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
  • J3ffJ3ff Member Posts: 4,236 ✭✭✭✭✭
    edited December 2016
    How much did they charge you? My volts dont work either. 
    · Share on Facebook
  • reneechris14reneechris14 Member Posts: 3,134 ✭✭✭✭✭
    To much 125 each tach 50 for 2"gauge.can get cheaper from greatlakes skipper but did not match. Faira Beebe online,there in Uncasville 
    2005 Rinker FV342  Pawcatuck river,Ct
    · Share on Facebook
Sign In or Register to comment.