Sorry if this is a bit long, but I'd love some input on a subject that I've been pondering for over a year.
A while back, I bought a '82 Mustang with the 3.3 I6, with the intent of bringing it back to life and using it as a daily driver. I spent good money putting in a new A/C, wheels, tires, shock, struts,... all the things you do to a car that's been sitting around un-used, and for the most part, un-maintained.
I had the 2-barrel carb professionally re-rebuilt by a shop that specializes in antique & show cars. I believe he did a good job, as the car did run well for a couple of weeks after I put the carb back on.
I usually get gas at the local Exxon or Shell. I had been filling the car at the Exxon by my house, but one day on my way home from work one, I stopped at Shell and filled it up with mid-grade. I don't remember any issues on the 6-mile drive home. The next day, I attempted to take it for a drive. I warmed it up in the driveway for about 5 minutes, and set off. It started idling very rough, and died at the next stoplight. It cranked, but would not fire until I slowly depressed the accelerator about 3/4. It drove fine, but when I'd stop, idle would degrade, and it would die. Repeat. Repeat. I finally pulled into a shopping center, where it died. I stepped out and heard a boiling noise. Popped the hood and discovered that the gas was boiling in the carb bowl. This was essentially flooding the engine while it ran.
I spoke with my carburetor guy and he did mention a customer's old Pontiac that had a similar issue. He cautioned that some carbureted cars have a hard time running on "modern" gas because it has a low boiling point. It's logical that when you shut down the car, air is no longer passing through to cool off the carb body, and the engine heat rises against the bowls (depending on engine design), causing the gas to boil while the car sits, essentially flooding the engine. He went on to say that he ended up installing a ventilation system on the carburetor in that Pontiac that activates at shutdown, to cool the carburetor and prevent boiling. He said that was the only thing that keeps that car drivable.
My issue: The Mustang was always hard to re-start due to this issue, before and after the carb re-build, and it didn't pose much of a problem. It was just a matter of depressing the throttle slowly while cranking, and it would fire. There were never any idling issues prior to this day, while it was burning Exxon gas. It seems that only after I filled it with Shell did this issue escalate and become an drivability issue.
My question: As alcohol has a low boiling point, is it possible that this batch of Shell gas had more ethanol than E10 is supposed to have?
A while back, I bought a '82 Mustang with the 3.3 I6, with the intent of bringing it back to life and using it as a daily driver. I spent good money putting in a new A/C, wheels, tires, shock, struts,... all the things you do to a car that's been sitting around un-used, and for the most part, un-maintained.
I had the 2-barrel carb professionally re-rebuilt by a shop that specializes in antique & show cars. I believe he did a good job, as the car did run well for a couple of weeks after I put the carb back on.
I usually get gas at the local Exxon or Shell. I had been filling the car at the Exxon by my house, but one day on my way home from work one, I stopped at Shell and filled it up with mid-grade. I don't remember any issues on the 6-mile drive home. The next day, I attempted to take it for a drive. I warmed it up in the driveway for about 5 minutes, and set off. It started idling very rough, and died at the next stoplight. It cranked, but would not fire until I slowly depressed the accelerator about 3/4. It drove fine, but when I'd stop, idle would degrade, and it would die. Repeat. Repeat. I finally pulled into a shopping center, where it died. I stepped out and heard a boiling noise. Popped the hood and discovered that the gas was boiling in the carb bowl. This was essentially flooding the engine while it ran.
I spoke with my carburetor guy and he did mention a customer's old Pontiac that had a similar issue. He cautioned that some carbureted cars have a hard time running on "modern" gas because it has a low boiling point. It's logical that when you shut down the car, air is no longer passing through to cool off the carb body, and the engine heat rises against the bowls (depending on engine design), causing the gas to boil while the car sits, essentially flooding the engine. He went on to say that he ended up installing a ventilation system on the carburetor in that Pontiac that activates at shutdown, to cool the carburetor and prevent boiling. He said that was the only thing that keeps that car drivable.
My issue: The Mustang was always hard to re-start due to this issue, before and after the carb re-build, and it didn't pose much of a problem. It was just a matter of depressing the throttle slowly while cranking, and it would fire. There were never any idling issues prior to this day, while it was burning Exxon gas. It seems that only after I filled it with Shell did this issue escalate and become an drivability issue.
My question: As alcohol has a low boiling point, is it possible that this batch of Shell gas had more ethanol than E10 is supposed to have?
