idle shake

have new vintage runs great off idle. but below 1200 it has the shakes. timing is right on. stock 1915 motor. carbs are sinked, only 2500 miles, kadron small carbs, any ideas? bill

what do you mean shakes? physical shakes, or sputters?

check the motor mounts?

Are the carbs jetted correctly?

clogged idle jets

always thought idle jets would make it stumble until it gets into main circuit. then fine this is shake like on 2 cyclinders. but over 1200 its fine.

Idle jet(s).....

Idle jet(s).....

He heard you the first time, Alan. ;)

hiccups

Hi William,

You say the carbs are synced -- but are you sure? You say it sounds like it is running on two cylinders -- maybe it really is.

When the engine is idling, pull a plug wire and see if the RPMs suddenly drop. If the RPMs do suddenly drop, snap the plug wire back on and try another plug wire.

The wire(s) you remove that cause the least drop in RPM are related to the cylinder(s) that are not running. If both cylinders on one side are not running, then reconsider your comment about the carbs being synced.

Mark

Bill, I don't know if Vintage is still making them like they did when they made mine, but mine does not have any choke. So until the baby warms up it sputters and backfires for a short time. After warm up (like five minutes in So. Cal. it is just fine. I don't know if they put automatic chokes in them now at Vintage.

Fred Adler
San Diego

Is this something that was there from first delivery. 1915cc isn't really stock for a T1 VW engine. Assume has street cam? I'd give it more miles to smooth out (break in period) before I'd give it second though. About time to adjust valves and timing - see if that has any effect.

I "sync'd" my carbs before I headed South for the Winter. Balanced them side-to-side and front-to-back. That was just after I installed a new set of manifold-to-head gaskets. Even used a synchronizer tool to balance them (unusual for me).

After I was settled here in the South, I took the car out and it idled such that the engine "rolled". Not a shake, per se, but it would rock rhythmically (that's hard to spell at 10pm) only at idle. Off-idle it was fine.

Without use of a synchronizer (OK, basically, I'm lazy and didn't want to find it where-ever it is) I looked at the two idle adjusters. One was dead on the stop, and the other was just a hair off the stop. Played with the idle screws on both sides just a little at a time (like, 1/8 turn) this way and that until it evened out and now idles WAY smoother. It used to idle and roll at about 900 and is now smooth at about 800-825 and I'm a happy camper. Off-idle, nothing changed. Indicated to me that there was a mis-adjustment in the linkage, but this band-aided it for now until I find my synchronizer and re-do it right (or...maybe not).

Think about your situation. Look at your linkage. You'll figure this out. It's either an adjustment or a clogged idle jet. Either way, it's an easy fix.

gn

thanks for the tips boys, turned out to be idle jets,i got fooled this time,also linkage loosened up. thanks bill