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Trolling value used for docking?

Discussion in 'Technical Discussion' started by Danvilletim, Jul 12, 2014.

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  1. Danvilletim

    Danvilletim Senior Member

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    Our 62 sportfish w 3412,s does 6.2knot at its slowest speed with on engine in gear. 7 knots with both... Cruising down the fairway is a pain and docking can be challenging since there is such a lurch when you bump it in gear.

    Boat has trolling values that we have not played with much. Are trolling values ok with switching in and out of gear?
  2. Capt Ralph

    Capt Ralph Senior Member

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    Depending on the clutch and controls. Get off the dock and experiment. Again not all clutches and controls work the same. Sometimes they engage fully and you have to go into trolling mode, Sometimes they can go right into trolling mode. You will not hurt the clutch if you keep your hands off the throttles.

    Downloading & studying the manuals for the clutches and controls may save some hunt & pecking time.

    BTW, do you have an extra slow idle switch somewhere on the helm's dash? Some 3412's had this also.

    The end if the dock, closest to the channel would be prefered also.
  3. Capt J

    Capt J Senior Member

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    No, trolling valves are never meant for docking and going in and out of gear a lot. They will go into gear with variable delays and never ever be predictable. If you have the cat controls, get used to the delay (about 2 seconds) and pull it out of gear before you hear it go into gear and you'll get a little bump in gear.....but not lurch.
  4. Danvilletim

    Danvilletim Senior Member

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    They are 3412 PEEC engines. 1350hp first gen electronic and I dont see a low rpm option. Which would be awesome if it could be added ( or discovered)
  5. Capt Ralph

    Capt Ralph Senior Member

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    Without the manuals and schematic you're not going to find it or even know if it's there. If there is a Cat marine shop close, go to them with serial numbers. Service managers (writers) usually can look some things up and help with a Go / No-Go plan.
  6. Capt J

    Capt J Senior Member

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    On your engines, it would either be on the plate that you access the controls with. Or, a seperate switch, usually a rocker switch that you can press and the rpms will go down when the switch is pressed. It would be a good question to ask the selling broker/owner. What RPM do they currently idle at?
  7. Pascal

    Pascal Senior Member

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    The boat I run has 1400hp 3412Es (2003) Normal idle is 700 giving about 6.5 kts. Low idle is 550 and 5.2 kts. Low idle is engaged with an pair of simple toggle switch at the helm
  8. Danvilletim

    Danvilletim Senior Member

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    No rockerswitch but boat is a repower so some stuff is funky. It idles at 600rpm.

    I does sound like the trolling valve will be good for no wake zones. We haven't figured out how to work them. There is a start, stop, and troll budget. Is this usual? What's the sequence.

    image.jpg
  9. Capt Ralph

    Capt Ralph Senior Member

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    Those are the the Cat panels I remember. With the schematic, an extra switch could be added to your existing harness. Again, you need the prints and manuals.
  10. Kafue

    Kafue Senior Member

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    How many hours have you spent running the boat?
    Getting used to delay, torque and the feel of the throttles makes the difference. Time on the boat makes it easy and satisfying.
    If you aware of the reactions to your throttles then it is only a matter of time before you coast out at 5 knots and moor at ease.
    Just my 2c. and yes I have been in similar situation.
  11. ranger58sb

    ranger58sb Senior member

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    Instructions for our trolling valves discourage shifting when engaged.

    We coast a lot, when entering the marina fairway and slipways.

    When we're docking and I'm shifting gears to jockey into the slip, I usually use each gear 2 seconds or less (usually closer to 1 second in gear)... i.e., I take it back out of gear as soon as I can feel the props start to respond. No lurch.

    -Chris
  12. Pascal

    Pascal Senior Member

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    600rpm is low and pretty close to the 550 we have at low idle which is probably why you don't have a low idle switch. I can really imagine a significant lurch when engaging at 600 even though obviously props and gearing will have an impact.

    When going thru a fairway, since th boat is moving there should not be be much lurching when getting in and out of gear to reduce speed and wake. When maneuvering, with engines and props that size you indeed rarely keep them in gear for more than a second or so as otherwise the boat will gain too much momentum.

    I hate having a delay on engine controls... We have the morse electronic controls not those 3412s and there is virtually no delay in engaging the ZF gears.

    As to the trolling valves, I have never had any... but you could use them to slow down in fairway then disengage them when you're about to dock.
  13. CSkipR

    CSkipR Member

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    My Mans idle at 600rpm and both eng in gear 7 knots. When docking I am bumping in and out of gear very quickly. It takes awhile to get use to it but practice will make it easy.
    Definitely don't use the trolling valves for docking. You have no control and getting in an out of forward/reverse quickly would be very tricky.