Results 1 to 14 of 14
  1. #1
    Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451

    Merc efi water pressure

    Have a 97 efi 200 0G528934 powerhead just rebuilt lower unit has 6 hrs on it now I have 0 psi at idle pees some put not like it should has 5 psi at 3 k mechanic said he put a new impeller in and t stats any suggestions? Pressure Was fine before rebuild thanks.

  2. Member Reel Life's Avatar
    Join Date
    Mar 2011
    Location
    Smithfield, VA
    Posts
    146
    #2
    Replace poppet valve assembly.
    Mark
    2003XB/225 Promax

  3. Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451
    #3
    Ok where is the popet valves on these my needle on pressures gauge is bouncing all over the place. And being I am running dubble the oil to break it in would cause it to idle poorly plugs getting fouled ? Let me know what of guy think. The boat had great water pressure before the rebuilt powerhead.

  4. Member Reel Life's Avatar
    Join Date
    Mar 2011
    Location
    Smithfield, VA
    Posts
    146
    #4
    It is located on the starboard side of the block at the bottom. Behind/below the electrical plate w/ switchboxes. 4 bolts and hose from top of block run to it.
    Mark
    2003XB/225 Promax

  5. Member cajunrgfm's Avatar
    Join Date
    Nov 2009
    Location
    Upstate Ny
    Posts
    2,698
    #5
    I have recently had some bad sierra impellers in the shop , my own sportmaster i took apart,re shimmed and put it back in the water,with a new impeller kit, and zero WP, put another impeller in and perfect again, i did my poppet while i was at it, but it was fine,could just be a crummy impeller or a bad gasket. Makes for a pita when you put all new parts in and gotta do it again

  6. Member Reel Life's Avatar
    Join Date
    Mar 2011
    Location
    Smithfield, VA
    Posts
    146
    #6
    Yep, a friend had the same deal. Impeller hub spun on a new impeller. Sometimes the poppet can be affected by heat or chemicals the block is exposed to during rebuild processes.
    Mark
    2003XB/225 Promax

  7. Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451
    #7
    I ordered the poppet valve keep my fingers crossed

  8. Member
    Join Date
    Sep 2017
    Location
    Clarksville Tn
    Posts
    26
    #8
    Did poppet valve cure your problem?

  9. Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451
    #9
    I put new thermostats in and I have pressure now. The mechanic had put aftermarket ones in it. I was told thermostats could not do that but as soon as I changed them I had pressure.

  10. Member
    Join Date
    Nov 2010
    Location
    Humble,TX
    Posts
    4,377
    #10
    Where they gutted? That's the only way I could see that. Or missing completely

  11. Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451
    #11
    No that's all I did changed them and had pressure

  12. Member
    Join Date
    Oct 2008
    Location
    MO City, TX
    Posts
    269
    #12
    You have the part # for these thermostats handy? I am seeing the same issues
    2000 BassCat Pantera 3
    2001 Merc Opti 200hp

  13. Member
    Join Date
    Jan 2012
    Location
    California
    Posts
    451
    #13
    Quicksilver 75692

  14. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
    Join Date
    Apr 2008
    Location
    Greenville, SC (US)
    Posts
    94,945
    #14
    Also need the gasket/seal (62386001). Two of each required, per engine.

    Sticking OPEN thermostat could cause low pressure... or some assembly problem.


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor