Update on my effort to get the car to run with the factory distributor

[Michael L.]

Guys,

I have continued to work on my 69 L-46 to get the car to run. I proceeded by returning to the MSD distributor but without the 6AL ignition and the car ran well. I then went back to the factory distributor and the car would not run. I then opted to put the 6AL ignition on the factory distributor to give the spark an extra jolt. When I did this, i opted to change the spark plugs again and I noticed that they were wet and fouled and reeked of gas. What I realized is that when I swapped out the Q-jet for the Holley stand in and MSD ignition, I didn't bother to connect the Holley's electric choke, and when I put the Q-jet back on with the MSD distributor and 6AL ignition, I did not immediately hook up the choke, but when I swapped back to the factory distributor I decided I wanted to give the engine the best chance to start so I hooked up the choke. After seeing what the plugs looked like I realized that the only way the engine has run is without the choke working on both carbs, so I decided to try to start the engine without the choke and the engine then started and ran well. Because the choke was not connected the choke blade at one point when the engine initially started flapped closed and the engine immediately cough and stalled. In the end the original problem may have been that the choke might be out of adjustment and is flooding the engine at startup. Of course with the dyno run three years ago the choke was not connected.

The question I have then is how do I adjust the choke blade and the high idle on this carb? I looked at some videos but my choke doesn't have the round black dial that the videos I watched have. I have zero experience working on Q-jets and the adjustment isn't obvious to me. Thanks for your help.

Mike

[Terry D.]

Re: Update on my effort to get the car to run with the factory distributor

Unless you are going for judging points I would buy a new carb and be done with it. If judging points are an issue surely some race shop in Texas can fix the carb.

[Michael L.]

Re: Update on my effort to get the car to run with the factory distributor

Thanks Terry. The car is otherwise running fine (finally) so I don't think I need to have the carb fixed. I just want to open the choke flap a little bit and turn up the idle speed when the choke is on. Anyone know how to do that?

Mike

[Mark E.]

Re: Update on my effort to get the car to run with the factory distributor

The choke is adjusted by bending the choke rod that goes from the thermostatic spring to the lever that operates the choke. The adjustment procedure for the choke and fast idle is in the CSM and in the instructions included in overhaul kits.

[Michael L.]

Re: Update on my effort to get the car to run with the factory distributor

Thanks Mark. I should have thought of checking the CSM.

On another note, in the meantime I have been continuing to phase in the factory ignition after confirming the car can run with the factory distributor. I now have all the factory engine components in place, including the distributor, coil, wires, etc.. With the MSD in place and with using all the other above factory components the car runs reasonably well, (perhaps a little fussy to start but not terrible and the choke is disconnected and I haven't adjusted the carb yet) but when I try to run it without the MSD the car still won't run. In my mind this eliminates all the factory components I listed with the exception of the ignition wires as the original problem, because when I run the MSD I have it hot wired to a toggled 12V source and I bypass the ignition key and wires. The strange thing is when I check voltage of the +coil wire when the key is in the run position I get 6-7V and when cranking I get 11-12V (checked without the car running), which I believe is in the correct range for normal operation. The ignition harness is new (I believe Lectric Limited IIRC) although not sure that matters. The final thing to check I guess would be to disconnect the MSD and bypass the ignition wires by hot wiring the coil with 12V power directly to confirm that it isn't the power of the MSD ignition system spark that allows it to run but is a fault in the ignition wires that keeps it from running when the MSD is disconnected. Can anyone tell me how long I can run the car with the factory ignition distributor and points with straight 12V before I fry something? If it isn't advisable to run it at all like this is there somewhere I can get a resistor to mimic the factory ignition wires? Any input on this is appreciated.

Thanks,
Mike

[Mark E.]

Re: Update on my effort to get the car to run with the factory distributor

Voltage while cranking and running is normal, so the ignition/engine harness is doing its job. Things I would check:
- Tight connection between points and negative coil terminal; check resistance
- Ground cable under breaker plate
- Points and condenser (Install new ones; MSD uses these only as a trigger with low voltage so marginal points may work ok with this system)
- Coil (swap it out with a known good one for troubleshooting)

[Michael L.]

Re: Update on my effort to get the car to run with the factory distributor

Thanks Mark, I agree it must be one of the things you suggested, especially since you explained how the MSD system works. Something that is sufficient to let it run with the MSD must not be enough to fire the factory components. I had assumed incorrectly that if it works with the MSD it eliminates it as a problem.

As for the choke adjustment, I looked at the CSM but I'm not sure where the fast idle screw on Rochester 4Vs they reference is, and there is no picture of it in the CSM. Is this the fast idle screw in the attached pic?

Mike

Fast idle screw.jpg

[Mark E.]

Re: Update on my effort to get the car to run with the factory distributor

See below. There's a sequence of steps for adjusting the choke rod, choke-pull off, secondary air door and fast idle settings. It's not difficult but it's important to understand how these are inter-related. Instructions with specs from a rebuild kit or the shop manual are good references.

0900c15280055da2.jpg

[Jeffrey S.]

Re: Update on my effort to get the car to run with the factory distributor

Mike,
The other thing to check is the choke pull off (the plastic pie plate shaped thing at the front) You said in your original post that when the engine started the choke plate snapped closed. It should open slightly as vacuum is applied to the pull off. Just a thought.
Jeff

[Michael L.]

Re: Update on my effort to get the car to run with the factory distributor

Thanks guys I will check those things.