Aside from the politics and social consequences of gasoline mixed with ethanol (about which "persons of good will may disagree") i have some serious concerns about using ethanol in some of our engines.
In the midwest we have had "10% ethanol" at the pump for more than 20 years; usually the pumps are marked for ethanol, but sometimes they are not. In the present situation ethanol will only become more prevalent. i have found that my wife's '52 Chevrolet 216 and the 235 that i ran in my two-door *would not* run on 10% ethanol. They act like they are strangling or vapor locking, no matter what the weather. Has anyone else had this kind of experience with ethanol? Does anyone have a cure for it?
God's Peace to you.
d
Inliner #1450
Advance your timing and/or use richer carb needles. Advance the timing untill the engine just pings under load and back off the timing untill it just no longer pings. It would also help to make sure your heat riser is operational.
I haven't had any problems due to the gas, at least as far as I can tell. Idles fine, proper throttle respone, no run-on or hesitation.
I guess I'm wondering what the condition of the engines are? stock or modified? new or tired? how do the plugs look?
Both engines run (ran) quite well on unleaded regular without ethanol. The 216 is an original with no service other than tuneups at 45,xxx miles. i first encountered this issue with the (stock) '54 235 iin my '52 two-door in the late 1980s, buying discounted gas from a CITGO station that proved to be an ethanol mix. In the 1990s in Illinois, whenever we (inadvertently) filled the 216 with an ethanol mix, it would strangle and behave as if it were vaporlocking from a cold start. After i realized what was causing the problem, we have studiously avoided ethanol.
Someone mentioned in another discussion that the jet size would need to be increased by 27 percent to use ethanol successfully. Is this a matter of "trial and error" for each specific case? Can specific larger jets for the Rochester be purchased over the counter, or must they be drilled? What happens to performance and economy with larger jets when ethanol is not available?
God's Peace to you.
d
Inliner #1450
Don, The 27% increase in jet size is for E85 which 85% ethanol and 15% gas. I go along with Gearhead. Could your engines be running way lean? What do the plugs look like? If you have a manual choke, the next time you are on empty you could put a few gallons of 10% in and run on part choke.
Larry
I was wondering when this discussion was would pop up. The Feds have outlawed MTBE additive from gasoline because of ground water contamination. Sooo they have substituted alcohol, up to 10% should not effect our carb rides however when you get over 10% then we will begin to see problems in jetting and timing, not being big enough etc. As the % of alcohol increases it is corrosive and will raise hell with our steel lines, tanks and rubber fuel and carb acceleration pumps/gasgets. Stainless is the way to go, I don't know what to do about the carb's itself, mabye amsoil PI additive or marvel mystery oil? We got a mess on our hands.
Don, I think Bald Eagle has it covered. My 292 was weak & wanted to miss if I tried a hard pull with it under 2,000 RPM. Pulling from 1,000 or 1500 it would crap out. Over 2,000 was pretty good. This was going from below sea level to 4,200 ft. I raised the metering rod, no change, went from a .092 to .095 main jet, no change & then just started advancing the spark bit by bit. Got it where it would pull pretty good thru the whole RPM range. Unfortunately, it would sometimes kick back on the starter when cranking so I had to set it back just a bit. Maybe by going up another jet size I can set it back a bit more. It definitely is slower burning & needs more time to do it. A richer mixture should burn faster. Doug
Thank you, gentlemen, for your thoughtful comments. If and when we are forced to run the 216 on an ethanol mix, we shall study on rejetting the Rochester and playing with the timing. Yet i hope that time does not come.
God's Peace to you.
d
Inliner #1450
There is another angle to this that is a bit advanced, recently the megasquirt EFI (MSII) module had a variable fuel sensor added to its operating software this allows it to detect how much ethonal is in the fuel and it will automatically adjust the mixture to suit. If your running a 1 BBL rochester on a 216 then a 2 hole TBI off of a late 80's 3.8 V6 will fuel the engine fine. For a 235 or 250 then a TBI off of a 4.3 V6 will be good. These parts are showing up in late 80's early 90's astro vans that are now being junked regularly. Or you could use 2 1 hole TB?I's off of a 1.8, 2.0 or 2.5 4 banger if oyu have a dual 1 bbl rochester setup. As oil continue to increase more ethonal will be added. So this issue is not going to disappear.
Here is a link to some else on Stovebolt who hd problems with 10% ethanol and his solution.
http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=5;t=000904 Larry