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Hello again my Packard friends. I had my 1937 Packard Six, 115-C in the shop for a couple of weeks while the wife and I were on vacation. I told my mechanic the exhaust manifold needed new gaskets as well as the tappet covers. Change the oil and give it a tune up with all new stuff, including plug wires. When I came home to pick it up it ran just fine, good pickup, good braking, no more leaking on the garage floor.
The first thing I did was fill her up with new ethanol gas (E85) and put a measured amount of lead additive (Lucas Safeguard brand) as was recommended for this older engine.
Then I took it out for a short 1/2-hour drive to town to get a haircut. When I came out about 1/2-hour later, the old girl was hard starting. It wasn't particularly hot outside, but I let it sit awhile in case it was overheated (?) and after a few minutes and continued pumping of the accelerator pedal, she turned over and started up, and away I went. When I got home, I shut it down and tried to start it up right away again, the same thing occurred. I had installed a new electric fuel pump on it earlier in May, so I don't think it's a gas issue (?) but maybe, I'm certainly not an expert on these fine old cars. Sometimes it just gets a little frustrating.
Any help is greatly appreciated.
Thanks,
Steve Weaver

Your problem is likely to be the E-85 gas. It is not at all suited for use in older model vehicles. Engines designed to operate on E85 have computer controls, very high voltage ignition systems, wide spark plug gaps, and other special equipment and settings to accommodate the ethanol, and the fuel system parts are designed to accommodate it. Even at that, gasoline engines do not run well on high ethanol blends. //// Get rid of the E85 and use E10 or ethanol-free gasoline. NEVER put E85 in a vehicle not specifically designed to use it, such as a "Flex Fuel" vehicle. E85 may cause damage to your old model fuel pump, fuel flex lines, and certain carburetor parts. It's a likely cause of hard starting and poor performance in an older low compression engine. E10 will give good results in older cars, and a lead replacement additive is not needed unless you drive the car very hard. I would remove the E85 as soon as possible and replace it with ethanol-free or E10 gasoline. I would not put the E85 in any vehicle not specifically designed to run on it, and I would not put the E85 with the lead substitute additive in it in any modern vehicle designed to run on E85. The additive might cause serious problems in a late model car designed for unleaded fuel.

Your Packard is designed to run on gasoline, not ethanol. Ethanol is an entirely different substance, and among other differences between it and gasoline, ethanol only has about 50% of the BTU content, or fuel value, of gasoline. Ethanol is more difficult to ignite than gasoline, and once ignited, it only yields about half the energy that gasoline does. I doubt if your Packard would start at all on E85 in cold weather, and it would perform very poorly once started. Ethanol is known to cause damage to older fuel system parts. It is generally considered safe to put E10 gasoline in older cars. E15 is not suitable, let alone E85!

Empty that "gas" out and use it for your lawnmower, and even then, your lawnmower may not even like it.

You can use regular unleaded 85. No lead is needed, as these motors are not high-compression and do not have high valve spring pressure.

E85 is not the same as "85 octane regular". E85 is a blend of 85% ethanol and around 15% gasoline and certain other non-ethanol substances. I would not put E85 in anything not specifically designed to use it. Only a few very late model vehicles are equipped to use E85. E85 is not a good fuel for any internal combustion engine.

The best gasoline for a pre-WWII Packard is 80 octane leaded aviation gasoline. That's not a practical choice for most people.

The second best-choice is ethanol-free unleaded gasoline, which is typically around 87 octane.

The most practical fuel choice for most people is E10 "regular" gasoline, which is usually 85 to 87 octane and is usually the most widely available and least expensive gasoline available in most of the USA.

Cars built before 1950 do not need "high octane" gasoline. Anything above about 75 octane is fine, and that includes most any gasoline you can buy today.

If "Tier One" gasoline is available in your area at a competitive price, it's an excellent choice. In this area, Tier One Sunoco brand regular is available at about $2.70 a gallon. It's a quality, high detergent gasoline. Tier One spec gasoline is available under several brand names.

Search: "Tier One gasoline" for information, brands, and availability.

There's a couple of problems running an old car on E85. One is that many fuel system parts are not very alcohol resistant and you will need E85-specific stuff which may be difficult to get, for example the accelerator pump system.

Second is that alcohol has much less energy per volume. E85 is about 35% less than E10. This will cause a variety of problems as the engine is sort of running lean all the time.

Some people have done E85 conversions for the high compression cars because E85 has a very high octane rating compared to the usual pump offerings. But I have heard that the carb jets have to be oversized and it's something that really needs to be done by someone who knows what they're doing.

For a prewar car, 87 octane is more than enough, so the only question is whether to pay extra for detergents at the pump or as an additive. They didn't really have them then, but it helps keep the carbon buildup away.

A great many older cars lost performance back in the day due to carbon buildup on the back of the intake valve heads and deposits in intake manifolds. The carbon deposits restricted airflow and reduced performance. Detergent gasoline will prevent these deposits and can remove or reduce existing deposits. Tier One gasoline can be especially effective in reducing or eliminating intake valve and combustion chamber deposits as well as keeping carburetors and intake manifolds clean.

If you want performance with E85, you need very high compression and a very high fuel flow rate, plus spark plugs designed to run a wide gap and an ignition system capable of supporting them. Ethanol's low BTU content must be made up for by burning more of it. (Richer mixture, lower MPG) It's a poor choice of fuel for internal combustion engines. It is completely unsuited to use in older cars for a number of reasons. E10 is acceptable, conditionally. Any ethanol blend over E10 is NOT acceptable for use in older vehicles!

Ethanol does have a high octane rating, or octane equivalency. That simply means that it is difficult to ignite compared to normal heptane, which ignites very easily. As far as that goes, water has a very high octane equivalency. That does not make it a good motor fuel.