Setting timing on a CMB alpha 27

Discussion in 'Gas Boats Forum' started by Roxyflash, Jan 11, 2019.

intlwaters.com

Help Support intlwaters.com:

  1. Jan 11, 2019 #1

    Roxyflash

    Roxyflash

    Roxyflash

    Well-Known Member

    Joined:
    Aug 21, 2003
    Messages:
    956
    Using a dial indicator set tdc to zero then the letter says to set timing to 1.2 to 1.5 line on rotor lines up with line on stator.I set it to .130 lining up the marks is this correct
     
  2. Jan 11, 2019 #2

    Buckshot

    Buckshot

    Buckshot

    Well-Known Member

    Joined:
    Dec 23, 2003
    Messages:
    3,388
    Location:
    Atlanta, GA
    The lines on the flywheel and ignition should line up when the piston is 1.2mm - 1.3mm BEFORE TOP DEAD CENTER. 
     
  3. Jan 11, 2019 #3

    Stuart Barr

    Stuart Barr

    Stuart Barr

    Well-Known Member

    Joined:
    Mar 24, 2005
    Messages:
    1,120
    Buckshot is right on setting.   CMB makes a dial indicator that screws into plug hole for doing this.  Makes it much easier for measuring proper setting.  I have these in stock.  However, I am going to be gone for 10 to 12 days.

    Stu
     
  4. Jan 11, 2019 #4

    Buckshot

    Buckshot

    Buckshot

    Well-Known Member

    Joined:
    Dec 23, 2003
    Messages:
    3,388
    Location:
    Atlanta, GA
    Bring me one of the dial indicators please.
     
  5. Jan 11, 2019 #5

    LohringMiller

    LohringMiller

    LohringMiller

    Well-Known Member

    Joined:
    Jan 25, 2017
    Messages:
    319
    Location:
    Eugene, OR
    It's easy to make an indicator holder from an old plug.  Cut out the insulator and turn a press fit piece with a hole for the indicator.  Add a screw for retention.

    Lohring Miller

    Timing measurement.JPG
     
    Last edited by a moderator: Jan 11, 2019
  6. Jan 11, 2019 #6

    Roxyflash

    Roxyflash

    Roxyflash

    Well-Known Member

    Joined:
    Aug 21, 2003
    Messages:
    956
    Stu I was thinking .060 using the fraction scale what do you recommend I have the indicator that was bought with the motors
     
  7. Jan 12, 2019 #7

    Dennis Somers

    Dennis Somers

    Dennis Somers

    Well-Known Member

    Joined:
    Oct 20, 2011
    Messages:
    96
    Location:
    G (greater) T (Toronto) A (area)
    .0472" to .0512"
     
  8. Jan 12, 2019 #8

    Roxyflash

    Roxyflash

    Roxyflash

    Well-Known Member

    Joined:
    Aug 21, 2003
    Messages:
    956
    The indicator is a metric unit so I wasn’t paying attention.I set it to 1.2 mm should be good now thanks for the help
     

Share This Page



arrow_white