401 nailhead with Qjet- idles fine until I put it in gear then it dies! It has a Switch pitch turbo 400. The only way I can get it going is to double foot it. What's the deal? Please help.
I didn't mention that it back fires through the carb when I hit the gas when in gear. It idles and seems to run just fine unti there is a load.
Get a vacuum gauge (they are cheap), and hook it to manifold vacuum. Then pinch off each vacuum line and watch the gauge for changes. Then spray a small amount of carb cleaner around the carb base and manifold to head junctions. Again, watch the gauge for a change.
Does the switch-pitch actually go to high-stall at idle? Where is the ignition timing set at idle, with the vacuum advance hose disconnected? Is there vacuum at the vacuum advance at idle? Does the vacuum advance work? Have you adjusted the idle mixture screws for highest vacuum/highest idle speed? (actually, I adjust for highest vacuum, then lean the mixture slightly so as to reduce vacuum by about 1/8--1/4 inch on each screw, 1/4--1/2 inch total.) What is the curb idle speed? Does the carb accelerator pump work?
Well I have been trying to check those things all day but the car will not start!! It acts like it wants to start if I pour gas down the carb. I do know that there is some cracking around the rubber top of the accelerator pump and there is some fuel leakage near the base of the carb. At this point I am thinking of pulling it off and either replacing it or having it rebuilt.
Turns out that the carb is a rochester 4jet, I guess that is different from a qjet. Anyway,I need to find out what Edelbrock carb will be the best fit for my 401.
Consider having your stock Rochester rebuilt before you toss it in the woods. It's probably going to cost you less without having to worry about retrofitting any lines or linkages.
You don't need a new carb, you need to diagnose the problem. An edelbrock won't be much better on a stock motor than a well built Q-Jet, but I can't speak for Rochesters, as I've never ran one. Have you checked all the lines for cracks or tears? Don't hate the carb, hate the vacuum.
Well, I was starting to hate the carb. I checked the lines for cracks and found nothing unusual. Another thing that happened was when my buddy tried to adjust the fuel/air mixture, he said that he could screw one side all the way in or out with no change.
This is always my first line of attack on an engine that has sat for a while or suspect a batch of bad gas, or otherwise runs poorly and carb is suspected. Gently remove top of carb, spray every jet and passage liberally with spray carb cleaner. Gently shake out excess or blow out with air and put all back together and try it. You can always pull it apart again to do a proper rebuild if this does not fix problem. These questions are hard to diagnose out of the blue. Did car run great until one day starts to die in gear? Or gradually got worse, rough idle in gear, until finally one day it dies in gear?
So it looks like I put the wires on the coil reversed after painting the :error:motor. It must have fried the points. Now it is up and running better but still backfiring through carb and misfiring a little I need to find a timing light and then start checking for vacuum leaks. Does that condensor on the coil need to be hooked up or is it just a noise suppressor for the radio?
