Logo
Click for Volvo Penta parts and manuals!
Results 1 to 6 of 6
  1. #1

    Default Is running outdrive in the full tilted up position any difference than turning it all the way?

    I got to thinking about how everyone gets their panties in a bundle when someone runs their outdrive on youtube tilted all the way up. I got to thinking, well I think turning it all the way port or starboard puts it at the same angle. Opinions? Just my thoughts, cause I noticed a slight hum when I was at the dock and looking back and saw my outdrive turned all the way to one side almost. I put it in the middle and the hum was gone. Keep in mind I'm paranoid, so the hum wouldn't be remotely noticeable to the average joe. I just thought i'd put out my opinion on the matter. So if you're at the dock and you have the engine idling (ujoints turning) try and keep the outdrive straight ish if you can, especially if you're like me where you like to leave the engine running while you grab the truck.

  2. #2
    Join Date
    Mar 2009
    Location
    Portland, Oregon,
    Posts
    11,681

    Default Re: Is running outdrive in the full tilted up position any difference than turning it all the way?

    ................
    Quote Originally Posted by Fishmaster23 View Post
    I got to thinking about how everyone gets their panties in a bundle when someone runs their out drive on youtube tilted all the way up. I got to thinking, well I think turning it all the way port or starboard puts it at the same angle. Opinions?
    To some degree (pun intended), that is true!

    Just my thoughts, cause I noticed a slight hum when I was at the dock and looking back and saw my outdrive turned all the way to one side almost. I put it in the middle and the hum was gone. Keep in mind I'm paranoid, so the hum wouldn't be remotely noticeable to the average joe. I just thought i'd put out my opinion on the matter. So if you're at the dock and you have the engine idling (ujoints turning) try and keep the outdrive straight ish if you can, especially if you're like me where you like to leave the engine running while you grab the truck.
    The good news is, you are typically at low engine RPM while doing this!



    Here's my take regarding bearing crosses (aka U-joints):

    They are designed and intended to be articulated.
    In other words, while under load, the needle bearings should move back and forth across a certain area the trunion surface.

    When we run our stern drive for hours with it aiming straight forward and trimmed "in", the bearing crosses are articulating very little.
    This point loads the needle bearings against the trunions.
    Constant point loading causes the needles to wear into the trunions more so in one tiny area as apposed to a car/truck drive line's bearing crosses.
    (this is also why greasing them only offers that "feel good" feeling only.... since we can't stop point load wear with more grease!)

    Also, with a stern drive, since there is no "coast" side thrust, they only wear on the "drive" side, leaving the "coast" side basically un-used.
    This is what makes them feel OK by hand, when they may not be OK.


    With a car/truck drive line, the articulation angle at the transmission and the articulation angle at the differential unit are nearly the same.
    (many Engineers will suggest a 3 degree angle)
    This gives them a longer life span than that of a Marine stern drive universal drive shaft.



    Next time you change your stern drive bearing crosses, pull a few bearing caps off and look at the trunions.
    Most likely you will see a small wear pattern where the needle bearings have been riding (point loading) on the "drive" side areas of the trunions.

    Compare that to your car/truck drive line bearing crosses.


    Bottom line.... keep doing what you are doing, and you will be OK.
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP drives

    "Intellectual growth should commence at birth and cease only at death." Albert Einstein

    Please... no PMs! Post your questions on the forum.

  3. #3
    Join Date
    Jun 2008
    Location
    Island Heights, NJ,
    Posts
    3,200

    Default Re: Is running outdrive in the full tilted up position any difference than turning it all the way?

    Depends on the drive.... 200 series drives have a drive lift system the is not designed to tolerate/absorb engine thrust, i.e.not an issue unless you are trying to propel the boat with the drive up.
    Capt Bob
    1969 23ft ChrisCraft Lancer
    Merc 5.7L 260HP/ Volvo 280

  4. #4

    Default Re: Is running outdrive in the full tilted up position any difference than turning it all the way?

    I went to driveshaft school in the 90's in Toledo at Dana-spicer. If a single u-joint (cross) has less than 3 angle, needle bearings in caps will not rotate . then it's solid so needles beat groves in reunion. That's called brinelling

  5. #5
    Join Date
    Jan 2017
    Location
    Salem Oregon
    Posts
    152

    Default Re: Is running outdrive in the full tilted up position any difference than turning it all the way?

    most outdrives will lift to a greater angle that they will turn side to side.... and when fully down, they arent but 5-8 degrees out of straight on, so no issues there.

    if you have the engine running around 1200rpm (or higher), and then lift the outdrive full up, you will definitely hear the stress that is being put on it... if you were to run it this way for for an extended amount of time, it will cause you a problem, and depending on how much pressure it has against it will determine how quickly it fails... early on since the invention of power trim/tilt, they learned that the cardan joint/U-joint/universal joint was prone to failure when the drive was lifted too far while it was turning, so they added a trim limit device so the drive shaft was protected when running, but the drive could be fully tilted for trailering/transport...

    in addition, when its run in the full up position, even if not in gear, it has a greater chance of sucking air into the impeller... when in gear, this problem amplifies due to the turbulence of the water near the water pick-up ports, and if one is traveling fast enough that the plane of the water shoots past the transom and outdrive which is raised too high, it will leave the impeller pick-up ports high and dry, and so impeller failure will occur... and the engine shortly afterwards.

    so, yes, if someone was to run YOUR boat that way, getting your "panties in a bundle" would be fully justified.

    keep in mind that the manufactures dont just think up random reasons to post unnecessary warnings in their manuals, just to give us more things to worry about... and just because they dont fully go in to details about the why of it, the warning should be heeded until you find out that it doesnt apply to the particular set-up on your boat..
    Last edited by centerline; 01-12-2020 at 04:28 PM.

  6. #6
    Join Date
    Mar 2009
    Location
    Portland, Oregon,
    Posts
    11,681

    Default Re: Is running outdrive in the full tilted up position any difference than turning it all the way?

    ...............
    Quote Originally Posted by Mikey N.C. View Post
    I went to driveshaft school in the 90's in Toledo at Dana-spicer. If a single u-joint (cross) has less than 3 angle, needle bearings in caps will not rotate .
    That is not necessarily true.
    A
    3 articulation angle will cause the needle bearings to rotate against the trunions! It may not be much, but they will change positions.

    then it's solid so needles beat groves in reunion.

    That's called brinelling
    Yes, that is what I was referring to as "point loading" damage.
    Last edited by RicardoMarine; 01-16-2020 at 07:53 AM.
    Rick ... aka Ricardo..... AQ series Volvo Penta repair
    Portland, Oregon
    28' SDN F/B w/ twin Volvo Penta 5.7L DP drives

    "Intellectual growth should commence at birth and cease only at death." Albert Einstein

    Please... no PMs! Post your questions on the forum.

Similar Threads

  1. 1986 Mercury 50hp, no spark in full down position. Runs when tilted up.
    By perry_merc in forum Mercury Mariner Outboard Forum
    Replies: 37
    Last Post: 06-23-2018, 02:02 PM
  2. Replies: 5
    Last Post: 12-01-2016, 05:48 PM
  3. Replies: 3
    Last Post: 05-12-2016, 07:50 AM
  4. Running in reverse with outdrive all the way up in trailering position?
    By juels98 in forum Mercruiser Sterndrive Forum
    Replies: 2
    Last Post: 06-02-2010, 08:17 PM
  5. Do all Quicksilver Remotes Beep when turning the key to the ON position
    By acleme1 in forum Mercury Mariner Outboard Archive
    Replies: 5
    Last Post: 05-10-2009, 10:01 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
  •