Hi all,

I've got a weird problem with my '73 as was wondering if anyone had heard of anything like this.  In the morning when I try and start it, the starter turns the engine for a few revolutions then stops.  I can hear the starter trying to turn but the engine won't go round.  If I try and turn the motor by hand using the crankshaft pulley, it's very hard to make it move.  When I do manage to turn it I hear a hissing/gurgling sound.  After this, the starter will turn the engine for a few more revolutions before jamming again.  Again, turning by hand will free it up, and eventually the starter will keep running and the engine will start.

Once started, it'll misfire for a few minutes then run smoothly and I'll have no problems with it for the rest of the day.  It has plenty of power when running.

I've recently changed the spark plugs and wires, cleaned and rebuilt the carb, timed it and replaced the fuel hoses to and from the fuel pump.  The oil level is fine, the battery has plenty of juice and I'm fairly sure that the starter is good.

My guess is that one or more of the valves are getting stuck, so the piston is struggling to move in or out of the cylinder causing the engine to jam.  Once it's started and warmed up, the valve loosens up and runs fine.

Before I dive under the valve covers, does anyone else have any words of wisdom?

Many thanks,

Matt

If I try and turn the motor by hand using the crankshaft pulley, it's very hard to make it move.  When I do manage to turn it I hear a hissing/gurgling sound.

I would be more inclined to think you have a starter problem or maybe (this is kind of rare also) a carb leaking Down overnight filling a cylinder up with raw gas locking up a cyl. If this was going on I would think you would end up getting gas in the oil. You dip stick would start showing a higher level.

I've had the problem with the exact symtoms you described.  Mine was due to gas leaking into the intake.  Like Ret.Bugtech said, it's kind of rare, but it does happen.  And when it happened, I did get gas in the oil.  It took a couple of days for me to figure out why the oil level kept inching up when I had a bad oil leak. :oops: Hearing a hissing sound from the compression leaking past the rings is normal wheny you turn it over by hand, but "gurgling" with it usually means there is a liquid involved.  Once it starts, it misfires for a bit then clears up?  Sounds like maybe it was flooded. :wink:   Also, did this start immediatly after you rebuilt the carb?

One other thing comes to mind . . . What kind of breather do you have on it?  Does it do it when the weather is dry or just when it's raining?  If it's got a stock breather, this won't have anything to do with it, but if it has one of those small chrome breathers with a paper filter, water can leak through the louvers in the deck lid and puddle up on the top of the breather, and leak into the intake.  I had that happen on a Baja Beetle once.  Just like gas (in liquid form) water won't compress.  If you get enough of it in a cylinder, it will lock it down.

The leak down can be caused by a faulty float cut off valve .

I have found that a lot of the needle/seat float valves in the kits were not very good and would stick opened and not open at all.

OK, I had a good look at the carb today.  Firstly, gas is definitely leaking into the intake - the dipstick is showing oil right up to the top, and it smells of gas.  Also the carb itself has gas on the outside of it.  I can't easily see where it's coming from, but it's there.  

I took the top half off the carb to see if the gas chamber was overflowing, but it wasn't.  It was about half full.  The float moves freely and as soon as I pulled it off I saw some gas come through the valve into the chamber.  I tested the valve by trying to push air through it whilst I held the pin in.  No air came through.  When I released the pin, air flowed freely.  I'm fairly sure the valve is working fine.

There are two brass screws on the outside that weren't very tight so I've tightened these up.  I have no idea what they're supposed to do but the gas leak was somewhere underneath them - they look like bleed screws (when I remove them there's a hole through the end of the screw like brake bleed screws).

I've retightened everything else and put it all back together.. I'll see tomorrow if there's any more leaking & flush the oil.

Stay tuned for the next exciting episode...

Because a picture can tell a thousand words... here's the carb, and the two points that gas leaks out...



Drip drip drip...

Think its just worn out?

The carb? Possibly.. I don't know how long it's been on the engine, or even how long the engine has been in the car.

You have some wear on the shaft causing the leak, but there is something else that is going on. Gas has to be coming from somewhere causing it to pile up on the butterfly. Not being there to look at it I can't be  sure whats wrong,
 but I still think you have a problem with the needle and seat(float valve) or the float . Like Big Dummy said maybe its just worn out but I don't know.

      You have the 30-31 carb. conversion with the adapter. If you replace the carb , replace it with carb just like the old one.  Your engine is suppose to have a 34mm carb but for god sake don't buy one of those.
      Mainly-Foreign says that there is no such a carb as a 30-31.  I guess I will have to show them  one .
         :lol:  :lol:
    F.Y.I.  A leaky fuel pump diaphragm can cause gas to fill up the crankcase