TheSamba.com :: View topic - Moved now gas mileage is horrible *Solved*

Fri Mar 19, 2010 1:35 am

Quote: I have also noticed that the mileage drop with ethanol affects carburetored cars more than today's computer controlled EFI. It also eats up a lot of the older carb parts.

No it does not eat up old carb parts. I soaked two accelerator pump diaphragms for 3 months in an isolated location. One was in 89 octane gasoline with no ethanol content, the other in 190 proof grain alcohol which is pure ethanol. Both showed no degradation what so over.

Most of the Brazilian ACVW's are also a testament to this. They run ethanol, only changes to them are jetting and timing.

Fri Mar 19, 2010 7:50 am

Myself and the rest of the streetrod/muscle car guys in my area would not agree with your scientific test.

This stuff is not 190 proof moonshine (like your test) when it's added at the refineries. It's eaten up the diaphragms in two of my Holley fuel pressure regulators, the accelerator pump and other soft parts on many a Q-jet, Holley and Demon carb based on the local cruiser crowd.

Maybe the VW stuff you soaked in grain wasn't effected, but our NJ stuff surely is. Maybe the amount or formula is different? Adding Sta-Bil seems to help, but only prolongs the inevitable.

Fri Mar 19, 2010 10:13 pm

There ARE indeed some parts that are not ethanol compatible.

Though probably not too many made now-a-days. The differences in parts between a "flex fuel" car and a typical car are very few.

Ethanol.. well.. here http://www.change2e85.com/servlet/Page?template=Myths

I have had problems with my old carbureted cars ever since mandatory ethanol treatment here.

I thought it was disolving old bits of varnish or something.. but Then I had the same problem on my brand new honda eu2000 generators. Think its just dissolved stuffs getting crystalized in the gas. Crummy refineries or storage tanks. I get what looks like little clear pieces of sand. Only can find em when they get stuck in my EU2000 carbs since they have such a small jet.

As for trusting the science of garage gossip.. careful.. people die from that.

Sat Mar 20, 2010 9:39 am

I've helped a couple of the local guys convert their cars to ethanol (turbo cars) and I can attest that ethanol definitly will eat rubber components. We have to replace all the rubber including the O rings on the injectors with viton pieces.

To the OP I'd consider doing a tune up on the carb itself, maybe even a rebuild since its really hard to tell what may have caused the change in mileage. It could be anything from the air screw needing to be adjusted to the float sticking, a piece of dirt partially blocking the air jet in the car.... theres just so many variables.

Mon Mar 22, 2010 9:19 am

So I replaced the drum and have gone through a tank of gas. That definitely must have been my problem because I got about 18 from what I figured. I would consider it acceptable with the traffic and all.

Those of you just joining in, I had a drum with worn out splines causing the drivers rear wheel to drag the brakes sometimes.

Thanks to you all for the suggestions, I would not have found it so quickly because I was only looking at the engine.

Mon Mar 22, 2010 10:02 am

Pink MG wrote: Myself and the rest of the streetrod/muscle car guys in my area would not agree with your scientific test.

This stuff is not 190 proof moonshine (like your test) when it's added at the refineries. It's eaten up the diaphragms in two of my Holley fuel pressure regulators, the accelerator pump and other soft parts on many a Q-jet, Holley and Demon carb based on the local cruiser crowd.

Maybe the VW stuff you soaked in grain wasn't effected, but our NJ stuff surely is. Maybe the amount or formula is different? Adding Sta-Bil seems to help, but only prolongs the inevitable.

As others noted there are a few polymer based parts that do have some ethanol sensitivity....but what really screws up palstic and rubber parts is ....Methanol. There may be some in your local fuel.

Also...as you are nting...its not really the ethanol "alone" that kills you....its thecombination, most especially because of the water than ethanol blended fuel entrains. They do not call water the universal solvent for nothing. Ray

Mon Mar 22, 2010 11:00 am

TGOT wrote: So I replaced the drum and have gone through a tank of gas. That definitely must have been my problem because I got about 18 from what I figured. I would consider it acceptable with the traffic and all.
While I'm glad you are satisfied, 18 from an ordinary 1600 is still pretty horrible even with the 009 and a lot of traffic.

Max

Mon Mar 22, 2010 6:58 pm

Max Welton wrote: TGOT wrote: So I replaced the drum and have gone through a tank of gas. That definitely must have been my problem because I got about 18 from what I figured. I would consider it acceptable with the traffic and all.
While I'm glad you are satisfied, 18 from an ordinary 1600 is still pretty horrible even with the 009 and a lot of traffic.

Max

Considering the commute and how horrible my wife drives 18mpg (which was a rough calculation BTW) will get us by. I'll keep track of it for a while, see if it averages better

Mon Mar 22, 2010 7:05 pm

I think my poor fuel economy has to do with where/how I drive. I don't drive that far (it's only about 10-15 minutes into town), but I only get close to 13 MPG. But the other day, I drove to a car show, most of it was Interstate driving, at about 65 or 70 MPH. I think I got around 20 MPG then. If I had cruised at closer to 55 or 60 it probably would've been even better.

Wed Mar 24, 2010 2:17 am

Well neato... glad its fixed...
I used to get mid to high twenties on my carbureted super when in good tune. It was a newer mexican engine though. Newer... vs worn out. Not fuel injected. Had super big valve adjuster nuts too. Wonder if it had 1.4:1 rockers in retrospect.