Are we just biased about ethanol because of its other negative effects? My experience has been that it makes the problem worse but there is no doubt it is not the sole cause, any fuel will vapor lock in my cars under the “right” conditions. However picking up on some of the information, one of the main ideas that comes up every time vapor lock is discussed is avoidance of ethanol containing fuels and yet we learn that ethanol has a higher boiling point than the lowest boiling point fractions of gasoline which would lead you to conclude that ethanol fuels would be less likely to cause vapor lock. More comment on this would be of interest. Some interesting information here but keep in mind that Tom’s original question was for ideas that work particularly the use of additives. Good luck with your tour, let us know how it went. It is quite possible you will not have a problem particularly if you can keep away from hills and keep the car moving to keep the air flowing through the engine bay. The Packards have the vacuum tank over the exhaust manifold which combined with high under hood temperatures makes the problem worse than on cars where these conditions do no exist. The problem seems to worse on some cars no doubt due to the proximity of the fuel system to heat. The problem of high volatility fuel is far worse today that it was in 1931 as modern fuels have become increasingly volatile which is not a problem for the cars of today as they operate with fuel under high pressure where the boiling point is far higher. The gasoline on the market today is more susceptible to vapor lock than the fuel of a year ago and the corrective measures at that time are not adequate today. In that letter Packard referred to the above letter and stated in part: “It will be well for you to read this letter again because the situation has become even more serious. However, a further letter was sent to the dealers some 16 months later dated Jadvising that the previous modification needed to be replaced with a more drastic change where the carburettor float bowl needed to be fitted with a vent connected to the intake manifold. Some quotations from that letter are interesting: “The combination of high operating temperature together with blended fuel including very volatile fractions has in some cases caused trouble through the boiling of fuel in the vacuum tank, the carburettor and the line connecting these two units ……” A minor modification was suggested in the letter. The first was written Maheaded “ Boiling Gasoline”. I have copies of letters written by the Packard Motor Car Company to its dealers regarding the problem. I have restored three and driven them all extensively over the last 30+ years and they have all vapor locked under the same conditions. In winter my cars will run perfectly on any fuel including 10% ethanol and, incidentally they run fine on 10-15% kerosene and I suspect would run fine on 100% kerosene once hot. Adding kerosene does not change that but even though the theory may be unclear it has on many occasions been the only way I could keep running.Īgain I do not dispute the theory but I have found that octane rating makes no difference but 10% ethanol certainly does and must be avoided in hot weather. I have been on tour climbing and had to keep wetting the carburettor every 100 feet or so- not fun when there is no overtaking lane and traffic following.įuel is made up of many fractions with varying boiling points and the lowest boiling point fractions boil at very low temperature. But on a hot day when in stop start traffic or on a long climb none of the above are sufficient and a wet rag around the carburettor is needed but that is very temporary. I have relocated the fuel line away from the exhaust system, fitted heat shielding, fitted a bypass electric pump removed the engine trays to allow more cool air around the engine, raised the leading edge of the hood to allow more air flow into the engine bay. The problem with Kerosene is you need to dilute the fuel with at least 10 -15% for it to be effective and if all of the conditions are against you nothing works and I have tried everything. Others have reported improvements with Diesel fuel but when I tried Diesel, it made no difference. In answer to your question about additives I have found adding kerosene reduces vapor lock, I haven’t tried Marvel Mystery oil as it is not available here in Australia.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |