I bought this car to resell but it's so clean and straight I'm falling in love with her. Had carb rebuilt but still has issues. Will run fine for 20 miles then when I stop and start to accelerate again it will spit and sputter and go dead. Then have to hold pedal to the floor to get her cranked. Frustrating. I'm new to this little straight six engine so any advice would be greatly appreciated.
Get a new carb. Sounds like if it really is the carb it was rebuilt wrong. I'd be more likely to suspect the fuel pump though. also, holding the pedal down to the floor while cranking is a good way to flood it and not be able to start it. The way I learned from listening to Car Talk is to crank for a few seconds, wait a little bit, crank again, wait a little bit. Give it 1 or 2 pumps while cranking at most. Then if its not firing up from gentle treatment you've got something completely wrong in your fuel or ignition system, or totally dry bowls in the carb which is most likely a fuel pump issue. The next time it does it try and see if there is fuel in the bowl.
sounds to me like it's either vapor locking or the choke is misadjusted as mentioned above. and if you have to hold the gas pedal to the floor to get the thing to fire up again?.. you're probably already flooded at that point. So, you're likely doing the right thing in the sense that fully opening the throttle plates will allow much more air in proportion to the fuel already in the intake/combustion chamber which just leans out the mixture to get the thing started again.
I agree.. These online diagnosisis (<-) take you almost anywhere lol.. I am thinking low idle and possibly ignition related in combination.
My 76 is now going through a rusty gas tank issue. I am changing the fuel filter every week, until Christmas. I am going to order a new gas tank and change it then. Your engine problems sound just about like mine. What is happening to me is the sediment is getting past the filter and clogging my power valve. It idles like it has a pro stock camshaft in it, but runs like it's a stock 250! Check your fuel filter. Ken
After it quits and you restart it, does it belch black smoke or not? If it smokes it's flooding! No smoke, bad fuel pump, or crud in the fuel tank and fuel system! The reason I say this is if you had a choke problem the car wouldn't run well for 20 miles. Did you rebuild the carb or did you buy a rebuilt carb? I've had rebuilt carbs that had sat on a shelf for years, and had corrosion inside!
Thanks I had the carb rebuilt at a local shop by "The Master" of old carbs. The line that heats up the choke is missing and I can't tell where it came from on the exhaust so he told me to wrap a copper tube around the exhaust and put the other end in the choke. Haven't done that yet but I let it idle for 10 min before driving and the engine heat will let the choke open. Also added a clear inline fuel filter yesterday to check for trash in fuel.
Thanks. I see it now but it's broke off right there at the manifold. Guess ill try the copper tubing fix.
I've never heard that. Just cranking over the engine clears a flooded situation, why hold the pedal to WOT? Yes, it won't start while cranking to clear, but after a few cycles of crank wait crank wait you drain your battery a lot slower and it should fire normally. Anyway, the car talk guys explained it way better than I could.
I explained it in post #4 and it has to with changing the air/fule ratio in a quicker fashion. Otherwise it takes nearly forever to clear puddled fuel and wet plugs by just cranking the engine. Severe cases can even lead to light piston/ring scuffing from fuel wash. Better to get er' back on track as quickly as possible in those cases. And as far as the car talk explaination.. I can only assume they were trying to keep folks from burning out the starter since it's well known by now that continuous cranking can be pretty tough on them. Especailly an older one.
Copper tubing choke I called a friend asking for a piece of copper tubing. He said sure, and brought over a 3 ft piece with a nut on one end. My lucky day. The nut fit the choke on my carb. So, a couple wraps around my exhaust with the other end and I have heat to my choke. It's hotter than a $2 pistol too, right at the choke. I'll try to put the pic up of this filter. It's only half full with engine running. Should it be more than that? If so I guess I need a fuel pump. No luck with the pic. Keeps saying I don't have any pics to upload.
