• If this is your first visit to the iboats.com Boating Forums, be sure to check out the FAQ. To post a question or comment, begin by signing up. To start viewing messages, select the forum that you want to visit from the selection below.
  • ALL iboats Forum Members and Guests:
    To show our appreciation for your participation in the Forums, we're offering an exclusive Forums-only discount good for an additional 5% off your iboats.com order for a limited time.
    To redeem, simply call our Customer Service Team at 800-914-1123 (Open M-F, 9am - 8pm Eastern Time) and mention the Forums 5% off discount. Offer excludes engines, trolling motors, and electronics.

Announcement

Announcement Module
Collapse

Help Tip: If you have a question that has not been answered to your satisfaction in the archives, it is always best to start a new thread of your own. By starting your own thread, you will receive the maximum number of views by forum members.

Below are some additional forum policies in hopes of all iboats members will follow, Thank you.

1. Please do not reply to old threads or hijack existing threads. Old threads of a technical nature are like a library book, Please do not write in them.

2. Old threads should be considered archives and used for reference only. Please do not reply to them.

3. Do not take over someone elseís thread (aka hijack) with your own question, even if it is similar. If you have a question that has not been covered to your satisfaction in the archives, it is always best to start a new thread of your own.

4. If you have a question for the original poster (OP) and the thread is over 30 days old, send the OP a PM, he may not even visit the forums any longer, or may not notice your question in the old thread.

5. By starting your own thread, you will receive the maximum number of views by forum helpers that may not even notice your question when itís posted at the end of someone elseís thread. And those answers will be specific to your particular issue.

6. Please do not post to threads that have been inactive for more than 3 months unless you are the original poster. We have very active forums and any thread that remains inactive for that long should be considered "dead". It is especially confusing when there is an entirely new question posted to an old thread.

7. Posting at the end of any thread is considered to be hijacking the original posters thread which in turn subjects the thread to be closed if it continues to happen thus not making it fair to the original poster in the future had for some reason he/she needed to return for additional information or provide an update of the problem solved which is always welcomed within a reasonable amount of time frame.

8. Please note that you should see a red banner pop up near the bottom of each inactive thread asking you not to reply to old threads. The Red banner will read: Please note this thread has been inactive for 90 days. For the best results, please start a new thread.

Thank you all in advance for doing your part in helping iboats run a smooth ship.

Additional forum rules linked below.
http://forums.iboats.com/forum-rules-guidelines-405/
See more
See less

4.3 liter mercruiser- no oil pressure showing at gauge

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts


  • 4.3 liter mercruiser- no oil pressure showing at gauge

    Just changed oil in my 1999 4.3 liter mercruiser with Mobile 1 10-30 synthetic and a K&N oil filter. Showed good oil pressure when I warmed up the engine before the oil change and now that I have new oil and filter on and started the engine for initial warmup period it show's no oil pressure at the gauge. Engine sounds fine and oil level is up. Not sure if there may be goop in the sending unit or ?????????. Changed oil in a lot of engines and never had one not return oil pressure to the gauge. Scratching my head. Any ideas?


  • #2
    Re: 4.3 liter mercruiser- no oil pressure showing at gauge

    Ayuh,... Welcome Aboard,... probably be coincidence...

    Ground the sensor wire,+ see if the gauge pegs,...
    Plumb in a mechanical gauge,...
    Any Grease is Better,..... Than No Grease at All.......

    Comment



    • #3
      Re: 4.3 liter mercruiser- no oil pressure showing at gauge

      verify with mechanical gauge before you do anything, don't want to risk the engine.

      Comment



      • #4
        Re: 4.3 liter mercruiser- no oil pressure showing at gauge

        Plumbed in mechanical gauge. No pressure. Coincidence that my oil pump takes a dump between an oil change??? Strange. Also tried grounding the wire to the electric gauge and it does not seem to max peg. I suppose this 4.3 has the mechanical oil pump located inside the pan! Just my luck.

        Comment



        • #5
          Re: 4.3 liter mercruiser- no oil pressure showing at gauge

          Originally posted by Loaded Bullet View Post
          Plumbed in mechanical gauge. No pressure. Coincidence that my oil pump takes a dump between an oil change??? Strange. Also tried grounding the wire to the electric gauge and it does not seem to max peg. I suppose this 4.3 has the mechanical oil pump located inside the pan! Just my luck.
          if you have no pressure the valve lifters should be clacking away.

          Comment



          • #6
            Re: 4.3 liter mercruiser- no oil pressure showing at gauge

            zero oil pressure = pullin' the engine. pretty common for the pickup tube to drop into the pan.

            Comment



            • #7
              Re: 4.3 liter mercruiser- no oil pressure showing at gauge

              Crazy luck. I actually tried 3 different mechanical gauges and got no pressure from any of them but I noticed nice clean oil on the tip of the threaded part of the gauge when I pulled them out, so I figured I would turn the engine over to see if I actually had any oil at that point, when I did it there was some oil but not a lot until I pulled the cap off of the filler tube. I reinstalled the mechanical gauge and sure enough I have pressure again. Put the sending unit back on and my dash gauge is back to normal also. All I can figure is that by using the siphon type oil change through the dipsitck tube that I created an air lock in the system somewhere. Wow! sure glad I don't need to pull the engine! Thanks for you input and ideas. Sometimes it's good to walk away from the problem for awhile and talk to somebody rather than beating yourself up over it and overthinking. Ice is off the lakes, I'm goin' boatin!!

              Comment



              • #8
                Re: 4.3 liter mercruiser- no oil pressure showing at gauge

                All I can figure is that by using the siphon type oil change through the dipsitck tube that I created an air lock in the system somewhere.
                That shouldn't be possible.
                Don S.

                sigpic

                Please, no PM's (Private Messages) regarding boat/engine problems.
                That is what the forums are for.
                Only forum/moderator issues will be answered in PM's.

                Comment



                • #9
                  Re: 4.3 liter mercruiser- no oil pressure showing at gauge

                  Originally posted by Loaded Bullet View Post
                  .... All I can figure is that by using the siphon type oil change through the dipsitck tube that I created an air lock in the system somewhere. ....
                  Nope... Crankcase is externally vented... Can't pull a vacuum inside (or anything close to that)... This DOES NOT make sense.

                  Maybe a bit of crud in the sender hole that got blown out when you ran the engine with nothing in the hole?

                  Glad you're all fixed.

                  Chris.........
                  The world takes on a whole new perspective when viewed from 100' below...



                  1972 Bertram 'Bahia Mar' 20
                  2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
                  **
                  Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
                  **
                  Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

                  Comment



                  • #10
                    Re: 4.3 liter mercruiser- no oil pressure showing at gauge

                    Originally posted by don s View Post
                    that shouldn't be possible.
                    Snap!!!
                    The world takes on a whole new perspective when viewed from 100' below...



                    1972 Bertram 'Bahia Mar' 20
                    2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
                    **
                    Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
                    **
                    Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

                    Comment

                    Working...
                    X