Something strange is happening with my 351W

[Roger Bray]

Hi Guys,
I could really use some advice.
I have a 351W crate motor with a new ( 500 mi ) Holly 750 cfm carb.
The car has been running flawlessly since I put the new carb one last fall.
Today is a different story.
It's been about two weeks since I have started the car. The weather has been very hot here in KY with the exception of the last two days. It's now in the 70's.
So today I started the car up. I gave it some choke and it fired up as normal. It usually runs rough for a minute or so then settles down to a nice idle at about 800 rpm. Today was different. There seemed to be more white smoke from the side pipes from normal and I could not get it to settle down and keep running at idle. Also some with smoke was coming from the carb so I shut it down.
After it was shut off gurgling and bubbling noises kept coming from the carb. when I took the air cleaner off and worked the linkage to give it a little squirt of fuel the fuel turned to white vapor when it got near the throttle plates and started making the noises mentioned above.

I don't know if I should keep running the engine to try to let it up more .....

any help would be greatly appreciated.

Roger

[Roger Bray]

BTW. the fuel in the car is fresh. The last time that I drove the car it was raining. that was the first time that I ever drove it in the rain.
I have no clue if this is significant ... just thought I would put it ...

[FWB]

sounds like water vapor roger....from the humidity....let it warm up and see if it goes away...watch your temp gauge

[Roger Bray]

thanks FWB

[WardL]

If it continues to run poorly you might have experienced a phase separation in your gas tank. A phase separation happens when too much water gets into the gasoline. The system gets wet enough to where the water and ethanol would rather be separated from the oil part of the gasoline. The water and ethanol settle out at the bottom of the tank. The easiest way to check is to get a sample of fuel at the engine or off the bottom of the tank. If the fuel is cloudy or has a water phase on the bottom and oil phase on the top, your gasoline is worthless and needs to be pumped out. If you have a receipt you might go back to the station and they should pay for pumping out your old gas, disposing of it properly and giving you a fresh tank. The station will likely say they had 1,000 customers that day and no one else had a problem. That doesn't matter, they should fix it. This all assumes the gasoline contained 10% ethanol to start with, which likely it did. Good luck!

[Roger Bray]

all is well. I ran the car and warmed it up ... still ran rough. I let it set for a few hours and tired again. It ran perfect. I guess that when I warmed it up the first time it got the engine warm enough to evaporate the water.

thanks again guys. going to go for nice drive today