Just picked up a 1965 buick skylark with the orig 300 nailhead with the orig rochester 2bl.the carb has been rebuilt, it runs great, no lifter tick, doesnt burn oil ect.the problem i am having is it takes forever to start cold.if i spray starting fluid into the carb it fires right up.seems like to fuel bowl might be draining while parked over night.does anyone have any suggestions on what to check or ideas.thanks in advance, -Jimmy-
There are plugs in the main wells but I've never seen them leak. Theoretically you could siphon fuel if the main well air bleeds were plugged. http://www.oldcarmanualproject.com/manuals/Carbs/Rochester/2-Jet/Manual/MCarbRoch1973__2G_0010.htm Hoop
thats what i was thinking.i bought a new pump.going to install today.i am also going to read through that link too.thanks alot, any other help would be appreciated.-Jimmy-
interesting, explain why it would start with an out side prime.if it was flooding i could see a spark issue.not knocking your advise, just wondering why ignition?-Jimmy-
If you dont think that is good advice, let me show you some pistons with broken lands Yes starting fluid will start a car with a weak spark due to improper setting. Are you new at this?
A few things to look at, 1- does it spray fuel down the bowl when you move the throttle lever? 2- does the choke work? 3- does it have full voltage to the coil when cold? 4- is the battery good, back to low voltage when cold? 5- hows the points / ignition? poor performance when cold = poor starting cold Most any carb should be able to hold enough fuel to start at least once each morning even if the fuel line drains back. Once the needle and seat is above the fuel level, the bowl will not drain 100%. If the fuel wells are draining over night, you should be getting a heavy fuel smell and black smoke each morning. Does it take holding the throttle wide open to start? Thats a sign of flooding, can't imagine starting fluid helping that. Joe
One of the handiest tools I ever had was a spark tester. If I was out in the lot trying to see why a car wouldn't start I was fooled a bunch of times by weak spark. Those testers require enough energy (we use to calibrate our dis leads with a ST-125) to prove you have viable spark to run the car. Jut be sure to use the correct one, the ST-125 is for high energy systems, it takes 25KV in dry standard air. For non-hei you can use a a plug but clip off the center electrode. At atmoshperic pressure it only takes a couple thousand volts to jump a plug gap, you need to make it jump farther. But with so many electrode tip to plug shell variations it is impossible to say what the KV is like you can with a calibrated tester. Also, if you are using a homemade tool, make sure the spark is blue, yellow is close points or leaky condenser. Hoop
I've had 3 sbc do the same changed the fuel pump and they ran better than they ever had. I bet the cars starts runs a sec stalls won't fire couple hits of starting fluids to build up prime and she runs like a top
Tomorrow morning, don't start it. Pop the air cleaner and look down the carb and work the throttle. If you got no squirt, either the gas is draining back due to a bad fuel pump or leaking float bowl plugs. If you don't know anything about the fuel pump, replace it, cheap and easy enough. Make sure the choke is operational as well. The bad thing about starting fluid is it washes down the cylinder walls and can make the engine kick backwards if it doesn't fire. That action tends to blow the nose cone off the starter. Bob
Some good stuff there. You can tell Jon has been at this a while, who else uses the word footfeed these days.
One thing that used to happen to Rochester 2GCs was that if someone got overzealous when tightening down the air cleaner wing nut, it could warp the air horn out of shape, which would prevent the choke plate from closing. When you removed the wing nut and air cleaner to see what was going on, backing off the wing nut would release the strain, the air horn would go back to its normal shape, and the choke plate would seem to be operating correctly when you checked it. I had a '65 Lemans that drove me nuts one winter until I figured this out.
Also, most of the starting fluid I see on the shelves now has top engine lube in it to prevent the bore washing problems associated with the older stuff.
I don't know if your Buick has a starter with 3 wires, main batt cable, start purple wire and the other smaller wire that if you follow it you'll find it goes to the (+) side of the coil, I assume you have points. This wire gives a full 12 volts to the coil during the start only on the ign switch, I had a car one time that this fixed after a lot of head scratching.
The fuel is training back to the tank then takes for ever to get it back to the carb if you take the fuel line close to the tank as possable and make like a p trap in the line it will prevent drain back or loss of prime
Did you ever nail down the cause of your starting problem? I have a similar symptom. Upon closer inspection, I found that about a minute after I shut off the engine my carburetor would leak some fuel out of the throttle body where the shaft ends were visible, only to be immediately vaporized when coming into contact with the (hot!) intake manifold. I don't yet know if this is emptying my float bowl. If your problem got solved, I'd like to hear how you did it.
actually I did.adjusted the carb, and found that my advance plate on my distributor was sticking, keeping it in full advance.ordered a rebuilt dist from rock auto, installed, timed, full tune up. runs like as champ. -Jimmy-
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