Carb issue...Still

[streetrod1927]

In late May, I had the carb. on my cobra professionally rebuilt. (1961-62, 780 Nascar Holley w/center floats. The rebuild was perfect, I installed it an she started right up. I had only had to up the idle rpm by 200. The car ran great. no fuel/carbon smell , it fired right up each time the key was turned. Tonight, in anticipation of an after work cruise. I started the car and noticed a slight
rougher than normal idle and I observed the tach bouncing but the engine not really increasing or decreasing rpm as the tach indicated...and yes I installed a new nosinger tach when the MSD ignition was installed. I shut it down and checked for an obvious problem (vacuum leak etc. I also tapped the float bowls to perhaps unstick the floats if it were stuck. No luck, the entire garage (not to mention my home smelled of carbon setting of every detector we have ..I drove the car not less than 2 weeks ago and it ran well.... Help...any Ideas?

[767Jockey]

Ralph,
I think the car is a lost cause and you should trade it to me for mine immediately!

[Barnsnake]

If the engine speed and the tachometer don't seem to agree, it sounds electrical. It might be smart to disconnect the tachometer to ensure that it is not the problem.

You might have a look under the distributor cap. You could have some condensation or the center contact in the cap may have failed.
Put a timing light on it and see if the ignition looks steady and on-time.

[streetrod1927]

Thanks guys for the input. I didn't think about as it doesn't sound like a miss fire. The problem appears to be in the Carb. as it is almost the same as the initial problem but not as much fuel being pumped in. I called nisonger relative to the tach issue and they gave me some thingsto check before sending it back. Doug... I'm considering your trade offer...Yeah Right!!!!!

[CHANMADD]

When did you change the Tach and ignition...before or after the Carb???

[jhv48]

Check float levels first. Reason: gas smell.

[streetrod1927]

Tach. changed in '06 shortly after ignition change. Floats are what inititial problem was. These are LeMans bowls w/ center floats. Royal pain to adjust on car.....