Results 1 to 4 of 4
  1. #1

    Angry mercruiser 4.2L 300hp help

    my engines normally are great, just started making a knocking sound and loss of power
    I tried all the usual things, had all the injector tips replaced anyway, not that, cos I have 2 engines' the same I swapped some parts to try identify the problem, so if I disconnect the fuel solenoid it stops knocking and sounds great, but I get white smoke, so I think iv advanced the timing but at least its not anything inside the engine, so ive changed all the sensors, still same, anyone got idea what it could be

  2. #2
    Join Date
    Apr 2016
    barnegat NJ

    Default Re: mercruiser 4.2L 300hp help

    test fuel pressure knock ,sensor might be bad
    Last edited by johnnygjr; 09-10-2016 at 02:06 PM.

  3. #3

    Default Re: mercruiser 4.2L 300hp help

    Quote Originally Posted by johnnygjr View Post
    test fuel pressure
    how would the fuel pressure make it knock and then ok when remove wiring from solenoid
    do you think its a injector pump problem, although when I bleed it its very strong pressure
    I know by unplugging the solenoid wires it changes the timing and maybe compensating for something else

  4. #4

    Default Re: mercruiser 4.2L 300hp help

    what sensor are you talking about, I had the solenoid tested and I tried a new one anyway cos I had one

Similar Threads

  1. offshore V6 300hp
    By leconte in forum Yamaha Outboard Forum
    Replies: 1
    Last Post: 08-27-2013, 10:49 PM
  2. Big OMCbs 225 250 300hp
    By tonyaus in forum Johnson Evinrude Outboard Archive
    Replies: 1
    Last Post: 11-04-2007, 03:32 PM
  3. Cat 3116 300hp vs 350
    By mistahays in forum Caterpillar
    Replies: 6
    Last Post: 06-20-2007, 12:40 PM
  4. Magnum 350 300Hp
    By gkm24 in forum Mercruiser Sterndrive Archive
    Replies: 1
    Last Post: 06-12-2007, 08:09 PM
  5. 66 Ford 427 300hp
    By 66roamer in forum Ford Interceptor Marine Engine Forum
    Replies: 4
    Last Post: 03-04-2007, 07:42 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts