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EF-CS carb/ignition setup help.

Discussion in 'Daihatsu Hi jet' started by Steve S83, Feb 24, 2019.

  1. Steve S83

    Steve S83 New Member

    So after the timing belt broke on our S83P Jumbo I replaced and recut the valves, new cap and rotor, t-stat, water pump and tensioner, full top end gasket kit etc... Did a compression test after reassembly and was between 125-135 in all 3 holes cold. Idles great. Set the timing to about 7 degrees per what I've read on the forum and seems to idle and respond to throttle blips well. Problem starts when I try to drive. Runs fine through the RPMs until I shift into 2nd, then the motor bogs down and won't run. Almost like the timing is way off or down a cylinder. If I give a lot of fuel it will barley stay running but cannot take any load from the transmission. I have no clue what this could be. Carb settings? I haven't touched it since I refreshed the valve train but don't see why that would matter. Anyone with advice or similar experience, I would appreciate the wisdom.

  2. Jigs-n-fixtures

    Jigs-n-fixtures Active Member

    Probable causes of lack of Power: Insufficient ignition advance, secondary butterfly on carburetor not opening, metering rods/power valve not functioning, restricted exhaust, starving for fuel

    I’m guessing accelator pump, or a stuck advance plate on the distributor.
  3. Steve S83

    Steve S83 New Member


    I did some more digging, new plugs are black. Guess is running too rich which is flooding it, timing not advancing makes sense to me. Does that help narrow it down, forgive my ignorance but what is the advance plate on the distributor?

    Fuel is not restricted, actually flooded when I first tried to start.

    What is the metering rod/power valve?

    I'm new to OHC engines and know very little about carburetors. Being from the states and under 35, I've grown up on pushrod EFI engines so this has been a learning process.

  4. Jigs-n-fixtures

    Jigs-n-fixtures Active Member

    Start with the vacuum lines and carb. The 83s didn’t have the constant velocity carb, so i don’t think you have a metering rod, but I think you do have a power valve. But with the carbs we have the vacuum lines are a big source of issues.

    So, start with the vacuum lines, and check out the carb for things that should move but don’t. There’s a guy on YouTube, who has an S83, that was running rich, and it turned out that the choke was stuck.

    Re, the breaker plate. There is a cam inside the distributor, and the ignition points ride on that cam. When the follower comes to the lobe on the cam, the points open, the field in the coil collapses, and sends a charge through the spark plug. The breaker points are connected to the breaker plate, and the vacuum advance diaphragm, and centrifugal advance weights move the breaker plate, which changes the position of the follower on the points, and varies the ignition timing, the carb has so much vacuum advance, and so much centrifugal advance for a total advance. Not sure how many degrees total advance these engines want. Guessing I’d say around 35-degrees.
    Last edited: Feb 26, 2019
  5. Steve S83

    Steve S83 New Member

    So did some more digging over the weekend and it is defiantly a fuel delivery or fuel/air mixture issue. The spring that holds the choke closed was broken when I bought my truck and a manual choke cable was installed. This worked for the time I drove it prior to the timing belt breaking but now the choke cable and carb settings are not correct. What I need to know is if the choke flap should be wide open all the time once the truck is warm. I can get the truck to idle with the choke flap open but the RPM's are higher than I would like and if I adjust the idle screw to bring the RPM's down, the truck dies. If I retard the timing to bring the RPM's down the truck dies. I have the timing at between 7-9 degrees BTDC which I've been told is correct at about 1,000 RPM's. When I try to drive the truck once it's warm, it stutters and pops like it's not getting enough fuel but I wonder if this is choke issue not a fuel delivery issue? I know this is almost impossible to diagnose on the internet but any other advice is appreciated.

    Also, I did check the vacuum lines associated with the carb (checked them all actually) and the only issue I found was the one connected to the valve cover. It was split.

  6. bobjonah

    bobjonah Member

    does your distributor have two vacuum lines going to it ? if so, try switching them, One is for advancing and the other one retards the timing, If hooked up backwards, it will not run or accelerate well

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