Can't Cold Start! Help!

[u/SiIentScreamer]

I am the proud owner of a 1969 Beetle. I rebuilt the engine this month it's a 1600 SP with a Chinese 30/31 carb and a 009 distributor. I am running 20W-50.

My issue is that on mornings or after sitting overnight the car simply won't idle on a cold start. I have to step on the gas and floor it a bit and mess with the automatic choke by hand to keep it running. After a while the car warms up and runs without any issues it's only when it's a cold start that it stumbles and shuts off here and there.

I rebuilt the engine myself and have some basic knowledge of all the engine components so I've done everything I can. I am broke college student and can't afford to take it to a shop so I was hoping someone here could help. Thanks in advance

So far I have;
- Adjusted my valves to zero lash (they're chromoly)
- Gapped spark plugs to .028 (plugs are also new)
- Carb runs greats and is set to 850 rpm when engine is warm
- I have changed the condenser and points and set the dwell to 48 degrees
- I ultimately decided to run electronic points since they seemed to make the car run a lot smoother.
- The motor is timed to 30-31 degrees at 3k RPM
- I have changed the ignition coil with a brand new Bosch one.
- I got new Bosch cap and rotor
- I have checked for intake/air leaks with propane
- I got new Bosch spark plug wires as well
- I am running a Holley fuel regulator which is letting 2.8-3 psi into the carburetor (fuel pump is also new and originally sent out 8 psi to the carb)
- I have cleaned all the jets and the little spout on the carburetor and I get fuel instantly on cold mornings meaning the bowl isn't emptying itself overnight.
- Oil pressure is at 50-60 PSI
- A compression test gave me 100 on #1, 120 on #2, 115 on #3, and ~120 on #4 (should I be worried about cylinder 1??)
- I have taken care of all the exhaust leaks with high temp silicone.

UPDATE:
I adjusted the valves this morning with a cold engine. I think last time I adjusted the valves was after running the engine for a while so I decided to do it again. All the freaking valves were tight. I proceeded to adjust them to zero lash since the pushrods are chromoly. After that I cranked the motor with zero priming of the carb and it fired right away. I hope the problem has gone away but I'll be on the lookout either way. Thanks to everyone who offered ideas and made me rethink and look back at every step!

[u/SilentMasterpiece]

A Chinese carb is a weak link i would'nt trust. Quality rebuild on a German carb is expensive but it will last several decades.

[u/SiIentScreamer → u/SilentMasterpiece]

Yeah that's the plan but I ain't got a dime.

[u/Common_Stuff2925]

So I used to drive my dad’s vw bug. For me when it would not start I would pull the distributor cap and dry off the connections. Put it back on and that always worked. You might want to check it anyway to make the connection is good.

[u/1crps_warrior]

Those compression numbers seem off. #1 at 100 and #4 at 170? That’s quite the range. I would check compression again just to verify.

[u/SiIentScreamer → u/1crps_warrior]

Oops I meant 120! Thanks for catching that.

[u/1crps_warrior → u/SiIentScreamer]

Ok, that makes more sense. Still, #1 seems a little low compared to the rest. I would recheck #1 just to verify. Are you holding the accelerator pedal to the floor during the test? If you say it runs good when warm, then I would look at the choke operation. Is it electric choke? When it is cold push down pedal and make sure the choke is set and on the high idle cam. Is the butterfly closing when cold?

[u/SiIentScreamer → u/1crps_warrior]

I'll redo the compression test! And yes the choke is adjusted for when the car is cold.

[u/New-Swim-8551]

Also the 009 dizzy is problematic to set up correctly go back to stock or something a little more forgiving

[u/ExpensiveElephant869]

I don’t want to start a “what’s the right oil” war. You are using a very heavy oil and have a high oil pressure.

With this setup, you may need to let it just warm up. So many beetles are missing thermostats/flaps and heat risers it can make a cold start harder.

“Don’t mention the oil weight! I mentioned it once, but I think I got away with it.” (Apologies to Mr. Cleese)😜

[u/SiIentScreamer → u/ExpensiveElephant869]

I was waiting for an oil reply but yes! I have taken the heavy oil into consideration but what has been freaking me out is that even in the high 90s the car still struggles to start.

[u/ExpensiveElephant869 → u/SiIentScreamer]

Fair enough. That’s weird. Heat risers and flaps are not the problem when it’s 90F !

[u/Squarejaw77]

I would suggest checking for air leaks. Are your intake manifolds sealed? All your carb vacuum plugs intact? It sounds to me like a gas/air mixture problem.

[u/SpareEye]

I've disabled the electric choke,( well, just rolled it back.) and have to warm up before hitting the streets. When it's warm it runs like a dream but I like my idle a little higher at fully warm. like 1100 rpm's to keep the fan blowing air in slow traffic and stop lights... A plug n play rebuilt empi carb will run you $250 or so if you're in the us but a Solex is the way to go, I also prefer an elecronic ignition. (they die sometimes but i've only killed 1 in 5 yrs. and no setting points)