TheSamba.com :: View topic - 34-pic3 carb popping

Thu Dec 12, 2024 9:45 am

I got a 34 – pick three carburetor on my 1776. I’ve got everything adjusted starts right up, but there’s a consistent popping out of the carburetor, needle valve? I’ve taken it apart and cleaned everything and blown out the ports put it back on and readjust it and I get the same thing. Any ideas? Thanks guys.

Thu Dec 12, 2024 9:54 am

are the valves adjusted right ?

Thu Dec 12, 2024 10:08 am

Like a backfire? Check the valve adjustments as suggested, and make sure your timing is correct too.

Thu Dec 12, 2024 10:28 am

Time is correct and valves adjustments, correct but I’m gonna double check, thank you

Thu Dec 12, 2024 10:49 am

scott woodward wrote: Time is correct and valves adjustments, correct but I’m gonna double check, thank you
Please confirm how you have both set? Details/numbers/method pls.

Spark igniting the intake mixture... valve stuck open or incorrect ignition timing?

Thu Dec 12, 2024 12:00 pm

scott woodward wrote: ...but there’s a consistent popping out of the carburetor
Is the carb an original German SOLEX, or some aftermarket clone? Did this issue start suddenly, or has it always been occurring to some degree? Is it happening only at idle, or throughout the entire RPM range?

Does the car still drive normally with the usual amount of power? Has it always run pretty well before now? Have the valves always been adjusted to spec, or is the motor's maintenance history unknown? Do you know many miles are on it?

A cracked or burnt intake valve (though not very likely if always properly adjusted), as well as an overly-lean fuel mixture can cause the symptoms you describe. A 1776 will be inhaling more air than a 1600 and the carb may require different jetting to compensate. What size jets (main, idle & air correction) are in the carb now?

The level of fuel in the carb's float bowl can play a role here too. With the carb top and gasket removed, the fuel level should be about 3/4" down from the lip of the bowl with the float in place. The level is set by adjusting the thickness of the washer(s) under the inlet valve.

Thu Dec 12, 2024 1:08 pm

Can you make a video showing what it's doing?

Thu Dec 12, 2024 4:36 pm

Popping = mixture too lean.

Fri Dec 13, 2024 11:28 am

You guys are great thanks for all the tips number one. I waited till this morning when the valves were completely cold, the right side was pretty good except two were slightly tight, the driver side number three I readjusted but the other one one, the push rods had come off. You guys are so on so I reinstalled it readjusted everything check the points last night I rebuilt the carburetor cleaned everything out turn the key and the sucker fired up. Smooth is Silk sounds phenomenal. I’m a happy man, I’ve been waiting for this moment dreaming about it while doing chemo. Thank you guys and don’t forget to get your colonoscopy because it really matters. Thank you, Scott.

Fri Dec 13, 2024 11:44 am

Glad to hear you got it running well! :D

This just illustrates how robust these ACVW engines are. You thought it was running badly when in fact it was running on only 3-cyls! :shock:

Fri Dec 13, 2024 12:56 pm

Exactly!!

Fri Dec 13, 2024 4:21 pm

…and prayers for you, from me, for a successful treatment and a long and fulfilling life.