Fixed heat riser. Now motor runs terribly! Misfiring.

[BMW2002002]

Hey guys, I am new to the forum and out of answers when it comes to my 1970 Beetle.

I recently took out my heat riser and got all of the carbon build up out of it which was about 8 inches of solid carbon. I did this because my car had the classic symptoms of a jammed up heat riser.

Anyways, fast forward to today, the motor is completely put back together and it runs terribly. Once i finally get it started it runs like it does in the video i have provided. Very violently shaking the poop out of the car. It sounds like 1 or 2 cylinders aren't even firing..... I took out one of the plugs to see if it was gummed up or something and its totally clean. I played with the main jet on the carburetor and the two screws that adjust the idle (the big one and small one) and all three of them no matter how they're adjusted make absolutely zero difference in the way it runs. I should also note the carburetor was rebuilt recently.

Important to note in the video when i am revving it up it if full throttle. If i keep my foot on the floor it will only rev to about 3,000 RPM and then die down and shut off...

Where do i go from here??

Thank you SO much

-Spencer


VIDEO LINK
http://vid641.photobucket.com/albums/uu ... 0923_1.mp4

[Jim Ed]

Are the spark plug wires connected correctly according to the 1-4-3-2 firing order?
Did you set the timing correctly?

[ps2375]

Plug wires on in wrong order was my first thought also.

[Chip Birks]

Verify that your heat riser hasn't broken into the intake manifold. Saw this very recently on a 36hp manifold. It had 2 dead cylinders but awesome working heat in the manifold. Changed manifolds to one that we verified didn't leak between the riser and intake and the problem went away.