Announcement

Collapse
No announcement yet.

Engine noise diagnosis

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Engine noise diagnosis

    Hi all, iHave a 1976 Stag that has had an engine rebuild but was then left standing for up to 5 years.It starts and sounds very good apart from an intermittent engine noise. Hard to explain it buit it sounds like its coming from the Water pump area,front and centre of the V. Its like a spitting sound as the engine is running . And when revving its like a small dog barking and is accompanied by a slight vibration. The block and most ancilleries look shiny and new. Any clues as to a diagnosis or any pointers would be most appreciated.Thank you

    #2
    A recording might help but when I had a noise like that it was the bearing of the viscous coupling. I’ll try and find the video of mine when it was knacked. With the engine off does the fan spin by hand more than a blade’s width or 2?
    Last edited by Goldstar; 19 November 2020, 22:34.
    Paul - 3 projects, 1 breaker - garage built and housing 2 white Stags. One runs, one doesn't

    Comment


      #3
      Thanks Goldstar,i will check the viscous coupling tomorrow, didnt think i could post a video so i will try and sort one out.

      Comment


        #4
        A friends Stag had the same problem, sounded like the noise was coming from the water pump but was in fact the viscous coupling.

        As well as trying to spin the fan, try rocking the blades front to rear. There should be virtually no movement, if there is the bearing is knackered
        Neil
        TV8, efi, fast road cams and home built manifolds. 246bhp 220lbft torque

        Comment


          #5
          You could also try removing both belts in order to eliminate belt and bearing noise from alternator and power steering pump.

          Comment


            #6
            Hello, thank you to all you guys who tried to help last time i posted. Since then i have removed both drive belts and the noise is still there, the viscous fan has some play back to front and you can spin the blades quite a few blades by hand with the engine off.I am not allowed to post a video otherwise i would but i have removed the air filter and used along screwdriver as a stethoscope to pinpoint the noise, and it is loudest at the water pump cover . Hard to describe the sound another way but its like an awful metal to metal dry sound and it dont sound good. Any more opinions or clues will be much appreciated.

            Comment


              #7
              George. Now you have eliminated those items, and seem pretty sure the noise is coming from the water pump, I would say check it now before something serious happens. I know it is a tedious job, but if the pump or it's gear is about to fail, the consequences would be very expensive. Sorry to be a pessimist. Perhaps someone will come up with another suggestion.
              A sound recording facility would be such an asset to the Forum!
              Mike.

              Comment


                #8
                You can post a video on YouTube
                or if you want you could pm me i could give you my mobile number so you can WhatsApp me the video.I could then post it on here via my YouTube channel
                Gaz

                Comment


                  #9
                  Trial users can’t PM Gary. Do post it on you tube and post the link here though.
                  Paul - 3 projects, 1 breaker - garage built and housing 2 white Stags. One runs, one doesn't

                  Comment


                    #10
                    Found the video of the viscous on mine that went pop and uploaded it to YouTube https://youtu.be/X5RsjpT66jM
                    Paul - 3 projects, 1 breaker - garage built and housing 2 white Stags. One runs, one doesn't

                    Comment


                      #11
                      From what you say about the "slackness" and ease of spinning in your viscous coupling - if it isn't already failing then it certainly will soon. Try changing that first. They make a noise very much like what you describe.

                      When mine went I was expecting to find the sump dragging along the ground...........
                      Header tanks - you can't beat a bit of bling.

                      Comment


                        #12
                        Water pumps usually fail silently and without warning, Failing viscous couplings transmit their noise to the middle of the engine.
                        Neil
                        TV8, efi, fast road cams and home built manifolds. 246bhp 220lbft torque

                        Comment


                          #13
                          here are two videos that saintgeorge emailed me

                          https://youtu.be/PnChNBzD7vA

                          https://youtu.be/18PgJUXlKSw

                          Stags and Range Rover Classics - I must be a loony

                          Comment


                            #14
                            Sounds exactly the same as Goldstar's video above, so we can be pretty confident it is fan coupling.
                            '72 Manual O/d Saffron Yellow

                            Comment


                              #15
                              Definitely the viscous coupling in my opinion. Everytime you hear the noise you can see/hear the fan speeding up. Get it changed before it locks up and the fan blades disappear into the radiator !!

                              Roger
                              White TV8 BW35 no mods and now a Dolly Sprint to keep it company
                              So many cars, so little time!

                              Comment

                              canli bahis siteleri bahis siteleri ecebet.net
                              antalya escort
                              canli mac izle
                              pinbahis pinbahis dizitune.com
                              Working...
                              X