67 427/400 dies when stopping, need flow chart

[Larry S.]

My engine dies when slowing down to make a turn or stop at a traffic light. It cranks right up though. Today I had to shift into neutral (automatic transmission) when doing these maneuvers to keep it from dying. It dies whenever the rpms get below 1200 or so.

The problem started when I replaced a starter solenoid and installed N11 exhaust. I don't know of any connection there, although I did enrich the idle mixture to see if that was the problem caused by the new exhaust, but it didn't help. I've always noticed a power loss hiccup that I can feel and see a momentary dip in the tach (about 100 rpms), plus it does idle a bit rough.

Since there are so many places to start to find this problem, would someone help me with a plan of attack? BTW, everything is stock (to my knowledge) and pretty new (plugs, wires, distributor cap, points, etc.).

[Timothy B.]

Re: 67 427/400 dies when stopping, need flow chart

Larry,

If you shifted the car into neutral to go around corners then your problem is not electrical.. Bring the car to operating temperature like after a short drive and set the idle adjustment/air fuel emulsion screws.

Establish a stable RPM with the emulsion screws 1 1/2 turns out and adjust screws to the highest vacuum/ smoothest highest idle. After that, lower the idle to where it's stable again and readjust screws to make sure you are correct.

If for some reason the emulsion screws do not make any difference in idle you have carburetor problems..

[Bill C.]

Re: 67 427/400 dies when stopping, need flow chart

Have you checked float levels? May be low in center or high in the ends?

[Larry S.]

Re: 67 427/400 dies when stopping, need flow chart

No, Bill, I haven't yet checked the float levels, but that is the kind of thing I need to add to my list. Thanks!

[Jamie F.]

Re: 67 427/400 dies when stopping, need flow chart

Larry,
My 69 L68 starting doing that recently and if you think about the forces under braking which is the fuel in the float bowl moving forward under braking away from the metering plate and jets I suspected low float level.
When I check the center carb, it was low, but not really low. I adjusted it anyway and when I went for a drive the problem was cured.
I was surprised as the level was only down about a 1/4", but it must have made a difference.

[Tom L.]

Re: 67 427/400 dies when stopping, need flow chart

A while back I had the same problem, especially under hard braking. My idle was a bit low, about 650 stopped and in gear (I liked the sound better) and for different reasons I put it to spec, 800rpm I believe and the stalling hasn't happened since. Good luck!