66 SB hard to start when sitting for a month or so...any ideas why

[Ronald W.]

After the car has been sitting for a month or so I have to pump the gas peddle 20 to 30 times to get it to start. Runs fine once it is started. From then on starts right up hot or cold.

1) Carburetor bowls are not empty as I can see gas being squirted into the carb if I manually move the linkage back and forth (before I pump the gas peddle 20 to 30 times).

2) Choke plate closes after initial gas peddle pump

3) Carb has been rebuilt
4) Fuel pump replaced
5) Pertronix electronic ignition with new coil
6) Engine burns a little oil but nothing signifcant but there is an oily residue on the spark plugs
7) Spark plugs and wires replaced. Problem continues.

Any ideas?

Could the oil residue on the spark plugs prevent car from starting until gas "washes" them clean?

I'm stumped. Thanks in advance for any suggestions.

Ron

[William C.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

The OEM ignition system has a bypass for the ballast resistor to increase the firing voltage during cranking. I haven't the foggiest idea of how the pertronics is setup/supposed to work, but if all is as you describe, that is where I would start to look. The cranking motor will pull the system voltage down noticably, which is why the GM system bypasses the resistor during cranking. "tricks are for kids" is another way of saying that non-oem systems (like pertronics) don't always improve certain functions.

[Ray G.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Hello Ron;
Check for spark by;
1. Connect a timing light, with the timing light trigger taped in the on position, in a position you can see from the driver seat. (Obviously with the wiring clear of moving parts)
2. Turn the ignition switch to start and you will know immediately if you have spark at the spark Plugs.

Is the gas fresh, old gas looses octane.

my .02

[Joe M.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

One model of pertronix requires you turn the keyy and wait a few seconds before turning to 'start'.?

[Edward J.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Ron, If you have a volt meter, check the voltage at coil with the key on on position and then when you crank engine you should see battery voltage . I don't think that system uses a ballest res. if it does,key on and not cranking voltage at coil would be less.

[Clem Z.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

After the car has been sitting for a month or so I have to pump the gas peddle 20 to 30 times to get it to start. Runs fine once it is started. From then on starts right up hot or cold.

1) Carburetor bowls are not empty as I can see gas being squirted into the carb if I manually move the linkage back and forth (before I pump the gas peddle 20 to 30 times).

2) Choke plate closes after initial gas peddle pump

3) Carb has been rebuilt
4) Fuel pump replaced
5) Pertronix electronic ignition with new coil
6) Engine burns a little oil but nothing signifcant but there is an oily residue on the spark plugs
7) Spark plugs and wires replaced. Problem continues.

Any ideas?

Could the oil residue on the spark plugs prevent car from starting until gas "washes" them clean?

I'm stumped. Thanks in advance for any suggestions.

Ron

be sure the choke plate is closed completely as this is necessary to cause fuel to be pulled from the float bowl thru the booster nozzles. always wait maybe 10 seconds after pumping the gas to allow the fuel to vaporize as raw GASOLINE WILL NOT FIRE

[William F.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Right. Coil must get a full 12V when key is in start position. I had a similar problem and found the problem was with problem with solenoid which didn't let 12 V reach coil. Also, as has been recomended, be sure you have wiring regarding ballast as Pertroix recommends on their web site or give them a call And indeed, one version of Pertronix requires key to be on a few sec. before energizing-but don't leave key on for more tan 30 sec. without engine running or you'll damage Pertronix system.

[Timothy B.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

What kind of gasoline are you using, my 67 Corvette with Holley will evaporate the fuel in approx one week so what you report is not uncommon.

Go get a small plastic ketchup squirt bottle and fill the Holley with some gasoline. After the car has been sitting for a few weeks before starting the engine, remove the air cleaner and carefully fill the front bowl on the Holley through the vent tube without making a mess. I use a small rubber hose on the nipple end of the plastic squirt bottle that fits inside the carburetor vent tube then turn the bottle over to fill the primary float bowl. When you have put enough gas in the bowl turn the bottle upright and remove the rubber hose from the vent tube and there is no spilled gasoline.


If the engine starts like normal you don't have any problems.

[Gene M.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

"6) Engine burns a little oil but nothing signifcant but there is an oily residue on the spark plugs"

Well that does not sound good. Oily plugs and you expect them to fire?

[Duke W.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

After sitting for a long time the most volatile components of the fuel - those that have boiling temperatures of under about 120F and aid cold starting have mostly evaporated, so hard starting is not uncommon. Injecting some fresh fuel from a sealed container as previously described should help, but it's not clear to me if you are using the proper cold starting procedure. More detail on exactly how to attempt a cold start would be useful.

Duke

[Ronald W.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

After sitting for a long time the most volatile components of the fuel - those that have boiling temperatures of under about 120F and aid cold starting have mostly evaporated, so hard starting is not uncommon. Injecting some fresh fuel from a sealed container as previously described should help, but it's not clear to me if you are using the proper cold starting procedure. More detail on exactly how to attempt a cold start would be useful.

Duke

1. Pump the gas peddle about 10 times, Engage starter for about 15 seconds. If engine does not start which it won't,
2) Repeat step one
3) repeat step one. Engine will usually start to fire up but not enough for a full start
4) repeat step one. Engine will then start

[Michael W.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Pumping the pedal more than once or twice is futile. The accelerator pump chamber is empty.

[Clem Z.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Pumping the pedal more than once or twice is futile. The accelerator pump chamber is empty.

as long as there is fuel in the float bowl which feeds the pump well you will get a pump squirt

[Ronald W.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

as long as there is fuel in the float bowl which feeds the pump well you will get a pump squirt

I would agree as I can see gas squiriting into the carb as I manually move the carb linkage back and forth multiple times.

[Michael W.]

Re: 66 SB hard to start when sitting for a month or so...any ideas why

Then you're pumping far too much gas, verging on flooding it.