Results 1 to 6 of 6
  1. #1
    Marky's Avatar
    Join Date
    Jan 2013
    Location
    GB
    Posts
    62
    +1
    2

    Why check oil level when hot?

    Hi, probably a stupid question but here goes

    Why does the oil level (2008 RXT X) need checking when then the engine has been run up to normal operating temp as advised per the operating instructions?

    Surely if the hull is levelled ergo motor is level and left overnight then almost all of the oil will gravitate into the sump and give me a true level in the morning whilst cold and before start up?

    I am making an assumption that it is a wet sump and not a dry sump - am I wrong in thinking that (cant see an oil tank anywhere)?

    Surely its far safer to ascertain the correct oil level before starting the engine and using it until it reaches the correct temp?

    Thanks for your thoughts


  2. #2
    83Gator's Avatar
    Join Date
    Jul 2008
    Location
    St. Amant, LA
    Posts
    6,018
    +1
    304
    I asked this question once as was told "because the oil, when heated to operating temps, will expand in volume slightly, which will result in a true read...". I'm thinking it doesn't make that big of a difference for a stocker like myself operating between the bends on the stick, but if you're trying to squeeze every single unit of HP out of the 4Tec, then maybe so...

  3. #3

    Join Date
    Feb 2013
    Location
    Ontario, Canada
    Posts
    96
    +1
    8
    if my oil level is at the top off the bend and I wanted to bring it down to just over midway how much oil should I take out(when cold)

  4. #4
    moultrie rxp's Avatar
    Join Date
    Jul 2006
    Location
    South Carolina
    Posts
    172
    +1
    3
    I would pull out no more than 4 ounces and re check.

  5. #5
    Marky's Avatar
    Join Date
    Jan 2013
    Location
    GB
    Posts
    62
    +1
    2
    Quote Originally Posted by 83Gator View Post
    I asked this question once as was told "because the oil, when heated to operating temps, will expand in volume slightly, which will result in a true read...". I'm thinking it doesn't make that big of a difference for a stocker like myself operating between the bends on the stick, but if you're trying to squeeze every single unit of HP out of the 4Tec, then maybe so...
    Thats what I was thinking. I did a bit of searching on the net last night and there was varying opinion with the likes of Mobil oil techs saying check when cold as modern oil is designed to allow minimum expansion when heated hence almost no difference in level between hot or cold.

    For me its easier and I think safer to check when cold before starting. I will just make sure the level when cold is just below half way point so as to allow any slight variations due to thermal expansion if any.

    Thanks for your help

  6. #6
    The other thing to remember is that these engines are dry sump, with multiple chambers. Takes awhile to get things evened out. The crank "dry" sumps are actually blowby scavenged.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. How to check oil level on 2007 GP1300R
    By Maher Mighty in forum Yamaha How To & FAQs
    Replies: 6
    Last Post: 02-06-2012, 02:57 PM
  2. how to check oil level in 2009 fx sho
    By dbay79 in forum Yamaha How To & FAQs
    Replies: 1
    Last Post: 06-10-2011, 06:10 PM
  3. how to hook up oil gauge to check oil level
    By www.partnersautosales.net in forum Yamaha PWC Performance (2-stroke)
    Replies: 2
    Last Post: 08-06-2007, 10:32 PM
  4. Checking Oil Level Question??
    By Speed200 in forum 4-Tec Performance
    Replies: 4
    Last Post: 06-04-2007, 07:53 PM
  5. How to check oil level?
    By GeoRXT in forum Sea Doo Open Discussion
    Replies: 6
    Last Post: 05-11-2007, 10:54 AM

Posting Permissions

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