1. 'bant

    'bant Loyal Comrade

    My best guess is that something is causing the float to jam when you put the top back on the float chamber. If the float is jammed at the top then this would keep the needle valve shut.

    Once you take the top off again the float drops and the fuel starts to flow again.
  2. Comrade Norwegen

    Comrade Norwegen Puttering Along

    That may be the problem.
    I'll check it out in a few moments :)
  3. Comrade Norwegen

    Comrade Norwegen Puttering Along

    So, I've changed the float and adjusted the level once more in the chamber.
    I also disassembled the carburettor from the car and changed the O-ring for the main jet.
    The carburettor was fitted back to the engine and fuel was turned on.

    I managed to get the engine to sputter, but it didn't turn over just yet.
    The battery went flat after all the cranking lately, so it's on charge now till tomorrow.

    I think the level in the float chamber is just a bit low, so a but more adjusting in the float chamber and I think we're there!
  4. Comrade Norwegen

    Comrade Norwegen Puttering Along

    I managed to get it started today, but the car isn't running as it should, it is still low on power.
    I managed to get it started by overfilling the chamber - as i did before changing the valve seat.

    I'm thinking of sending the carburettor to Germany for an overhaul and have a better look at the condition of the engine.
  5. Wartburg353W

    Wartburg353W Loyal Comrade

    Have you checked the compression?
  6. Comrade Norwegen

    Comrade Norwegen Puttering Along

    No, I haven't checked the compression. I'll have a go at that!
  7. turbofiat124

    turbofiat124 Loyal Comrade

    With the older style carbs you need to fill the fuel bowl with some fuel before putting the lid on. Otherwise the float will get hung up on the side of the fuel bowl.
    No what keeps this from happening if you ran out of fuel (say had to switch to reverse), I don't know.
  8. Comrade Norwegen

    Comrade Norwegen Puttering Along

    Compression test gave me an idea of what the problem might be
    This is cylinder 1: DSC_0055.JPG

    And this is cylinder 2;
    DSC_0058.JPG

    I got received a new set of gaskets together with the carburettor refurbished kit, so I'll get cracking with this during the weekend ☺
  9. Comrade Norwegen

    Comrade Norwegen Puttering Along

    DSC_0059.JPG I took off the tin casing surrounding the engine block and removed the cylinder head on cylinder 1.
    The exhaust manifold is wet by WD40, but the rest of the block is soaked in oil/fuel
  10. Comrade Norwegen

    Comrade Norwegen Puttering Along

    Ok, so I disassembled the heads and came quickly to the conclusion that piston 1 is..Er...let's say kaputsky.

    One of the compression rings are completely missing and the piston it self has some damage.
    The inside of the head seems to be fine, no visible scratches
    DSC_0061.JPG
    Last edited: Oct 30, 2015
  11. mbeamish

    mbeamish Loyal Comrade

    Your options are
    Oversize pistons and a local rebore of your old cylinders
    Complete piston and cylinder set
    A complete recon engine

    It would be worth splitting the case and seeing what crank is like . If the crank bearings are worn then probably best to bite the bullet and get a complete engine
    Comrade Norwegen likes this.
  12. Comrade Norwegen

    Comrade Norwegen Puttering Along

    I think I'll go for a new cylinder and piston set.
    I cannot afford a new engine nor oversized pistons as of now..
  13. mbeamish

    mbeamish Loyal Comrade

    Oversized pistons and a local rebore is by far the cheapest option. You can buy new pistons for as little as 20 euros . Rebuilding only the top of your engine will be a total waste of time and money if crank is badly worn. Check the condition of the cranks first it only takes less then an hour to look at crank
  14. mbeamish

    mbeamish Loyal Comrade

  15. Comrade Norwegen

    Comrade Norwegen Puttering Along

    Thanks for the link!
    Their prices were a lot lower than Ldm and trabantwelt.

    I'll contact them tomorrow ☺
  16. mbeamish

    mbeamish Loyal Comrade

    Good luck I have not used them personally but a friend bought a couple of trabant cranks from them and said they were OK quality. Your other option if you are not in a hurry is oversize genuine DDR pistons still turn up on german ebay at reasonable prices
    Comrade Norwegen likes this.
  17. Comrade Norwegen

    Comrade Norwegen Puttering Along

    Excellent, thanks :)
  18. Comrade Norwegen

    Comrade Norwegen Puttering Along

    Ok, half a year later now!
    New engine, new carburettor which is tuned to the engine, new ignition and a whole bunch of other parts!

    So, yesterday I finally got to install my new Project 601 ignition system and the engine was running fine apart from it needing small adjustments to the timing.

    Today it didn't want to start and the carburettor is leaking through the overflow beneath the engine and the spark plugs are wet.
    The ignition circuit works fine, the sparks work as they should whey turning over the engine.

    I checked the float and valve. The float is not bubbling when submerged and the needle valve is shut properly when blowing into the fuel line
    Any tips on what the problem might be?
  19. mbeamish

    mbeamish Loyal Comrade

    Sometimes when the float bowl gets completely empty the float can jam open and petrol pours out of the over flow taking the top off the carb and then replacing it with the float bowl full works. It happened a few times to me . No real idea why but it does happen
  20. 'bant

    'bant Loyal Comrade

    I would take the fuel hose off the carb end and let fuel run into a jam jar. Check that is is clean, no particles that could block the needle valve intermittently and that there is no water in the fuel.
    Check the float level. If the float is too low it might not shut the needle valve fully.
    I would also suggest checking if the float sticks in the float chamber at the lowest point.
    Turn the fuel supply off when you leave the car and/or park the car nose down until you have found the cause.

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