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Does running gas with ethanol cause problems for older engines?

Some say you need hardened valves but then you hear of folks who have drove their stock motors for years on gas w/ethanol in it w/no problems. I have never had a problem w/any older motors I have ran w/ethanol base fuels. My brother drove his 39 Dodge as a daily driver & would put 1000 miles plus a week on it w/the stock motor & drive train w/out any problems what so ever.
A lot of it has to do w/the amount of nickel in the block & how hard the motors life has already been. If you're building a fresh block then by all means have hardened valves installed in the head...joe

My 1953 3800 has 39,977 miles and runs great. No smoke no leaks so I think I will wait on the overhaul.

The ethanol causes more problems with carburetors and other fuel system parts than internal engine mechanical troubles. Ethanol-added fuel goes stale much faster, so unless your truck is a daily driver, you'd better use fuel stabilizer regularly. Some early type rubber parts have a habit of developing leaks when exposed to ethanol, and there's a possibility that some of the epoxy coatings that get applied to the inside of fuel tanks can deteriorate when exposed to ethanol. Basically it's nasty stuff! Carb King calls it "deathanol"!
Jerry

I have not had any problems running ethanol but I don't run it unless I have to for one reason. Fuel mileage. I get far better mileage with regular unleaded in everything I drive than I do with 10% ethanol. So much so that it is cheaper for me to pay the extra .10/gal. than to run the ethanol blend.

Ethanol has less BTU per gallon then gasoline, thats the reason for the poorer mileage. also its less dense so I'm assuming that more can get thru your carb jets per minute. I have been using Seafoam for a couple years for a stabiliser and have had good luck. only good thing about ethanol is that it picks up any water drops and lets your engine burn it rather then collecting in your fuel tank and rusting the bottom.

You're confusing two different things. Ethanol has nothing to do with valve life. Back when the bolts were made, the gasoline had lead in it. Besides raising octane, the lead helped lubricate the valves. When leaded gas was eliminated in the 1970s, some folks had increased valve wear.

The ideal air/fuel ratio for an internal combustion engine is 14.7:1, by weight. 14.7 pounds of air to 1 pound of gasoline, for instance. If a fuel has a lower specific gravity (weight) it takes more volume of that fuel to produce the same weight and thermal energy (BTU's). When Dad started using alcohol in the family-owned race car back in the early 1950's, Carter Carburetor reccomended that he increase the cross-sectional area of the main jets X10, approximately 3 times the diameter of gasoline jets. When they finally got a 300 cubic inch (bored & stroked) flathead Ford engine running right on an alcohol/hydrogen peroxide mix, it was getting 8 laps per gallon on a 1/4 mile dirt track!
Jerry

There is a website called www.pure-gas.org and they have a state by state breakdown of where to buy ethanol free gas. If you find one in your area you can submit it to them, and they will add it to the list once they verify it. There are 90+ stations in Texas that are ethanol free. And over 2800 nation wide according to the site.

Just FYI

I think Hotrod Lincoln must have been a Physics or Chemistry major. Man, you are one smart dude!!!! I agree that ethanol isn't a problem, but I have to Highly reccommend using unleaded seats on the exhaust valves. I have seen way too many heads coming in to the shop with knife edge exhaust valves. JMHO

Humble Newby

I had a lab rat for Union Oil, who used to run the bench tests on engines tell me that the lack of lubrication provided by leaded fuel would only be a problem during heavy loads and uphill driving. But I would agree that hardened seats at overhaul is only smart.

I've pulled lots of 848 heads with beat out valve seats. I live in the hills & like to haul loads & just plain stand on it so's I can listen to my fentons & dual pipes. I will always have pre smog/unleaded era heads on any engine done with hardened exhaust valve seats. It always comes up in one of these posts about them being improperly installed & causing all kinds of problems. I've had 4 of 5 heads done this way in 2 or 3 different shops & never had any problems Or heard of any body else who did. unless you've got something that sets in the garage most of the time except for the yearly parade hardened valve seats need to be installed in the exhaust.