Announcement

Collapse
No announcement yet.

Engine falters at 4,000 rpm when accelerating

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

  • Engine falters at 4,000 rpm when accelerating

    When accelerating the engine will only get to 4,000 rpm then it will not accelerate any further. It almost seems like it cannot get enough fuel. The engine will accelerate fine when not under load. I have new SU HS6 carbs from Moss installed. 1975 TR6 with 80,000 original miles. Any ideas?

  • #2
    Points or Pertronix,Gadget ?
    Driving a 1973 TR6
    Doing ZS carb repairs
    email kencorsaw"at"aol.com

    Comment


    • Gadget_tr6
      Gadget_tr6 commented
      Editing a comment
      Older pertronix

  • #3
    Originally posted by Gadget_tr6 View Post
    When accelerating the engine will only get to 4,000 rpm then it will not accelerate any further. It almost seems like it cannot get enough fuel. The engine will accelerate fine when not under load.
    Classic symptoms of fuel pump failure. That's one possibility.
    Clamp fuel line, remove the fuel pump, unscrew the screws, clean the crud from filter on top, check the diaphragm for tiny split. If it was big crack it wouldn't make 4000rpm.

    Ha. If the fuel pump checks out okay, that possibility will be eliminated. Wear disposable gloves when working around fuel.
    Last edited by SapphireBlue72; 08-10-2018, 09:19 AM.
    Walt
    CC80954 '72 TR6 original condition.
    poolboy rebuilt the Z-S Carbs. Philstr6 rebuilt both rear hubs.

    Comment


    • #4
      I've had that happen due to a bad condenser.

      Tom

      Comment


      • #5
        Originally posted by Gadget_tr6 View Post
        When accelerating the engine will only get to 4,000 rpm then it will not accelerate any further. It almost seems like it cannot get enough fuel. The engine will accelerate fine when not under load. I have new SU HS6 carbs from Moss installed. 1975 TR6 with 80,000 original miles. Any ideas?
        With this limited information, I can only ask if you know what needles are in the SUs. There are several available with different shapes for this carb. Was the engine capable of higher rpm with the original ZS?

        Dick

        Comment


        • #6
          I had a similar issue with my HS6 equipped car. I found that by retarding the timing just a bit things smoothed out considerably without the 4K hesitation. I believe I’m running 14BTDC (indicated) at present. I’m also running an older Petronix which I believe doesn’t seem to present the issues of the newer units (knock on wood).

          Comment


          • #7
            "Older Pertronix".....If you've fooled with the ignition timing prior to noticing this faultering at 4k it could be that you've introduced a 'phasing' problem...something not unknown with Pertronix and one reason Jeff@ Advanced Distributors does all he can to discourage it's installation in the Lucas 22D6 distributor in a TR6.
            Maybe you could install points and condenser, then retime the ignition for those components...see what happens
            Driving a 1973 TR6
            Doing ZS carb repairs
            email kencorsaw"at"aol.com

            Comment

            Engine falters at 4,000 rpm when accelerating

            Collapse

            Search

            Collapse

            There are no results that meet this criteria.

            6-Pack Statistics

            Collapse

            Topics: 37,391   Posts: 469,585   Members: 8,136   Active Members: 307
            Welcome to our newest member, rschlemm.

            Upcoming Events

            Collapse

            Working...
            X