No announcement yet.

air in fuel system '84 Mako

  • Filter
  • Time
  • Show
Clear All
new posts

  • air in fuel system '84 Mako

    I am the proud owner of an '84 21 footer with the 86gal below console fuel tank. I am having a problem with air in my fuel system. I (and my mechanic) have ruled out the engine itself. (2000 Merc Optimax). I have replaced the entire fuel system from the engine to the tank pickup with only minimal if any problems noted with connections etc. My next area would be the tank pickup itself. Here I run into my questions. On my tank after disconnecting the fuel hose, removing the anti-siphon valve, removing the 90 degree fitting, and removing the bushing threaded into the coupling welded into the top of the tank I am left with no apparent way to remove the tank pickup tube itself. On every other tank I have ever worked on when I removed the final coupling/bushing from the top of the tank the pickup tube came out with it. The pickup tube does not appear to have ever been part of the final fitting and is not showing any signs of having broken off. Is anyone familiar with this setup and can tell me how to remove the pickup tube for inspection/replacement. Also, can it be replaced? I don't see any fuel pickup tube replacement kits in any of the catalogs. Thanks for any help. Capt. Miles Schlichte- Producer Fishing Charters, Gloucester, MA
    Gloucester, MA

  • #2
    Just checking to see if the answere go automatically to my email or if i have to check back here. Miles
    Gloucester, MA


    • #3
      Miles Please put your Hometown,State in your siginature. It helps everyone know where you are at and maybe can direct you to something local.

      Now to your question. Yes I'm familar with what your talking about with the removable pickup and that is the best way to have it.

      The problem is the fuel line hooks up at the front of the tank, under the console.

      The tank has an enterional line that goes from the front of the tank where the line hooks up under the console and goes to the back of the tank inside the tank. It's welded in.

      One of the guy's had a problem with that enterional line with a crack in it.

      There's no way to test that without cutting the tank apart.

      Here's my suggestion and it's going to be a PITA.

      Go to the aft end of the tank thru the inspection Pie Plate and drill a hole to match the right size pipe plug for tapping. Tap the hole and install the pickup that you have seen in the past, with the removable tube. T-H Marine makes those pickups. They have a light green straw that goes down into the tank. It's not listed on their website, but I confirmed it thru Killinger Marine as I have seen the pickups at their place in the parts dept.

      That's the best I can tell you without pulling the tank and all the BS that goes with it.


      • #4
        Hi Warthog, thanks for the quick reply. I think I follow you but I don't know what a enterional fuel line is. I assume you meant an internal fuel line? You say it is permanently welded in place and is not removable? If that is the case I can follow your suggestion about drilling and tapping for a new pickup. Unfortunately, my boat does not have a pie plate over the rear section of my fuel tank. I have a large rectangular hatch that outlines the entire tank. To remove that would entail removing the entire console etc.. I can access the front portion of the tank where the existing pickup tube is located by removing an access panel set into the large tank hatch. However, I am pretty capable and would have no problem cutting a pie hole and installing a pie plate afterwards. I would like to get it as close as possible to where I need to drill and tap though. If we use the rear edge of the main tank hatch as a reference point where abouts should I cut my 10 pie hole? In other words, does the fuel tank extend further aft than the cutout outline? If so, I should probably cut the hole aft of the rectangle cutout. If not, just forward of the rectangle tank cutout should be the better location. Any ideas? Also, where is T-H Marine and Killinger Marine located so I can order the pickup tube I need prior to starting this project? Also, thanks for the suggestion on my hometown and state on my signature. I will take care of that as soon as I send this. thanks for your help. Miles
        Gloucester, MA


        • #5
          Sorry my spelling get's off some times. You are correct.

          T-H Marine is a manufacture. They will not sell to you direct.

          Killinger Marine is in Pensacola,Fl. [850]477-1112

          Your going to need to know how deep the tank is. They have several diffrent lengths.

          As to where to install the pie plate, I can't help you as my boat is totally diffrent. I would put the pickup just off center. There could very well be a center baffle there and you don't want to run into that.

          I would place it about 2in foward of the aft end of the tank.

          That may very well make the pie plate be half on and half off of the removable tank hatch. I wouldn't want it like that. Maybe go down to a 6in pie plate and have the aft edge of the pie plate 1in forward of the aft edge of tank hatch. Does that make sence?


          • #6
            Ok warthog, thanks for your help. If anyone else has done this I sure would appreciate any input. I will do a little more research and investigating before I get started on tearing things apart later in the week. I will let ;you know how I make out. Miles
            Gloucester, MA


            • #7
              I had fuel flow problems on my 1976 25'. We cut a new hole in the deck, installed a new cover on the hole and put a new pickup in the rear of the tank. Then we ran the fuel hoses from the pickup under the deck up to the center console where my fuel switches (front and back tank) are.

              That helped a great deal with my problem. There were other issues, but this is certainly doable.

              I didn't do the work myself, so I'm not sure how the mechanic cut a new hole in the tank, which was full of fuel, without blowing himself up.

              Good luck.

              Tom[br]Pompano Beach, Florida[br]1976 25\' Mako[br]


              • #8
                Have you thought of running a plastic pickup tube from the front of the tank to the rear using the exsisting hole in the front of the tank? This would be easier than cutting your deck to gain acess. If necessary you can weight the end of the plastic tubing with lead to make sure it stays on the bottom ot the tank. Tony
                79 Mako 23[br]85 Wellcraft 18 fisherman[br]Hammond, La.


                • #9
                  spectrout77 hits the bullseye. There you go. What could be easier?

                  There's another "Why didn't I think of that?" answers. Good job Tony.
                  Ole Joe
                  Just floundering around
                  Shrewsbury, Pennsylvania
                  1978 Mako 25, Sold