Rogillio Posted September 5, 2014 Share Posted September 5, 2014 What fuel do you burn? Octane reducer? Lead addative? Someone suggested i burn Coleman fuel aka white gas. Anyone use that? Link to comment Share on other sites More sharing options...
R.White Posted September 5, 2014 Share Posted September 5, 2014 I use unleaded petrol straight from the pump. There seems little point in using a lead additive in these low compression, low revving engines because a) they don't get enough use to pocket valves and these engines were designed before lead was even added to petrol. If I am proved wrong then I will get hardened valve seats fitted to the block but until then I am happy to take the risk.Ray. Link to comment Share on other sites More sharing options...
Rogillio Posted September 5, 2014 Author Share Posted September 5, 2014 I am more concerned about getting combustion at the low compression. I was told that compression in these engines is only about 50 psi.....and told modern cars won't even run at low compression....therefor I should use a lower octaine fuel.i obviously need yo educate myself on the chemistry of octane and combustion. Link to comment Share on other sites More sharing options...
Rogillio Posted September 5, 2014 Author Share Posted September 5, 2014 Just found this.....The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.So it was suggested to use a lower octane rating such as white gas. Link to comment Share on other sites More sharing options...
Bleach Posted September 5, 2014 Share Posted September 5, 2014 I looked at a 26 Sedan a few years ago and the owner said you had to add some oil to the fuel. He said he ran it on straight pump fuel and it ended up seizing on him and ended up with an expensive rebuild. I've never heard that anywhere else. Link to comment Share on other sites More sharing options...
MikeC5 Posted September 5, 2014 Share Posted September 5, 2014 I agree with Ray... The only thing I might worry about is the ethanol present in most fuel available (in U.S.). Ethanol can cause issues in fuel systems not designed for it, mostly rubber o-rings and such. Unless you are using an electric fuel pump I doubt the Dodge has any of these materials in it. I would use 87 octane without added ethanol if I could find it. Using a fuel that is lower octane than recommended may cause knocking, true, but I'm sure the reverse is not true (higher than required octane). http://blog.hemmings.com/index.php/2014/04/11/tech-101-octane-the-facts-and-the-fiction-behind-those-higher-priced-fuels/ Link to comment Share on other sites More sharing options...
Rogillio Posted September 5, 2014 Author Share Posted September 5, 2014 So what IS the issue in using too high an octane? Link to comment Share on other sites More sharing options...
MikeC5 Posted September 5, 2014 Share Posted September 5, 2014 I really don't think there is one.... Link to comment Share on other sites More sharing options...
nearchoclatetown Posted September 5, 2014 Share Posted September 5, 2014 So what IS the issue in using too high an octane?$$$$$ Link to comment Share on other sites More sharing options...
R.White Posted September 5, 2014 Share Posted September 5, 2014 (edited) If an older engine knocks it's most probably because of imminent bearing failure. Not to be confused with "pinking" or pre ignition. If this happens then the engine is too far advanced. Remedy; retard the ignition until it goes away.We don't get more than 5% ethanol in our fuel.....yet!Ray. Edited September 6, 2014 by R.White (see edit history) Link to comment Share on other sites More sharing options...
robert b Posted September 6, 2014 Share Posted September 6, 2014 (edited) If an older engine knocks it's most probably because of imminent bearing failure. Not to be confused with "pinking" or pre ignition. If this happens then the engine is too far advanced. Remedy; retard the ignition until it goes away.We don't get more than 5% ethanol in our fuel.....yet!Ray.Have done over 350.000 miles on pump fuel in my Dodge 4 over 35 years and only had to replace one exhaust valve in that time due to the adjuster coming lose and valve head burning. I have only relaped the valves twice over the years when the head was of due to blown head gaskets,set the ehahaust at 0.008 " and the inlet at 0.006 engine cold and let them work . The car is used every day and is run on unleaded fuel, the mileage that you will do would not hurt the valves at all .I think to little use will do more damage.Ray have bracket and will put in post next week Bob. Edited September 6, 2014 by robert b (see edit history) Link to comment Share on other sites More sharing options...
R.White Posted September 6, 2014 Share Posted September 6, 2014 Many thanks Bob. If I can return the favour somehow just say. 350,000 miles I think is proof that the engines can take it. Can the transmissions stand up to that kind of work I wonder? My odometer reads 95,000 and the gearbox is very worn but then it might have been round the clock a few times!Ray. Link to comment Share on other sites More sharing options...
robert b Posted September 6, 2014 Share Posted September 6, 2014 Many thanks Bob. If I can return the favour somehow just say. 350,000 miles I think is proof that the engines can take it. Can the transmissions stand up to that kind of work I wonder? My odometer reads 95,000 and the gearbox is very worn but then it might have been round the clock a few times!Ray.Yes Ray , well almost . one inpit shaft and second gear , Two clutch plates , One tailshaft ,One set of front and rear wheel bearings, Two brake relines, an four exhast mufflers(one I had exlplode due to bad ignition conection ) and I think there was six of seven sets of tyers, about four batteries,the generator and starter have never been repaired and the spark have never been changed in that time, that about as much as I can remember at the monent Bob Link to comment Share on other sites More sharing options...
cahartley Posted September 6, 2014 Share Posted September 6, 2014 I've used "straight from the pump" gas ever since it came out in everything from teens and twenties tractors to teens and up cars and everything else I have that takes gas.It has never caused a problem.When the off season arrives I shut off the gas, run whatever I won't be driving or using dry and leave them that way until Spring.I've never had a problem unless the fuel system wasn't clean in the first place or a system had 50 year old, or older, soft components that were overdue for replacement anyway. Link to comment Share on other sites More sharing options...
Rogillio Posted September 7, 2014 Author Share Posted September 7, 2014 That is good to know. It is starting to sound like a myth that you should not run pump fuel in vintage cars? Link to comment Share on other sites More sharing options...
R.White Posted September 7, 2014 Share Posted September 7, 2014 That is good to know. It is starting to sound like a myth that you should not run pump fuel in vintage cars?Absolutely. I would urge caution, however, when replenishing the oil. I gather you are having an engine rebuild. Even with a clean rebuilt engine there is no benefit in using synthetic oil. Some people would not even use a multigrade but that is probably being over cautious. We have discussed this topic before on this forum if you want to check it out but the general feeling is that a low detergent oil is less likely to deliver suspended particles to the bearings.Ray. Link to comment Share on other sites More sharing options...
JACK M Posted September 8, 2014 Share Posted September 8, 2014 Synthetic oil has more lubricity. It may find the leaks easier too.It is better oil but probably not necessary. Link to comment Share on other sites More sharing options...
Spinneyhill Posted September 8, 2014 Share Posted September 8, 2014 1. A good dissertation on oil: www.widman.biz/Corvair/English/Links/Oil.html.I use a full detergent oil in my 1930 Dodge 8 and am converting to 10W-40 CI-4 as per the above. The author bottles oil for Bolivia (read around his web site). The car has a canister bypass oil filter (of which a replacement is 150USD on ebay, so in due course I will be finding a way to open one up to fit a modern filter element) so I change the oil at 1000 mile intervals. (BTW, the owner's handbook says to change the oil at 1500 mile intervals.) I have looked at the bearings: there are no bits embedded in them. You should use top grade oil in your new engine if you want maximum benefit - once run in it will be clean and there will be little chance of bits getting into the bearings if you start with modern oil and change it frequently - the crud will drain out with the hot oil. Note the CI-4 specification has maximum ZDDP, which is why it was specified. Remember that the first number (10W above) is about viscosity when cold, which is when most engine wear occurs, so thinner (to a point) is good when starting up as oil pressure can be pumped up quickly. Study the graphs in the above article. This applies to splashers too.2. Use the lowest octane fuel you can get. Mid-20s fuel was probably not much more than about 65 octane. Higher octane fuels burn more slowly than lower so you are more likely to burn exhaust valves and the fuel is not fully burnt when it is pumped into the exhaust. You just heat up the exhaust system - I have heard of a Ford Model A exhaust manifold glowing dull red at night when running high octane fuel. In addition, high octane fuels will knock ("pink") in a low compression engine with the ignition set where it is, sometimes inaudibly. Knocking results in holes in piston(s), as well as extra load for the bearings. The answer is to retard the ignition or use low octane fuel. You may need to retard the ignition anyway. Mine seems to be OK at factory settings on 91 octane (our lowest). Link to comment Share on other sites More sharing options...
MikeC5 Posted September 8, 2014 Share Posted September 8, 2014 The early Dodges (pre-27?) didn't have an oil filter and the oil pump is a very small volume/pressure device that probably wouldn't work well with an add-on filter (filters cause a pressure drop). As such, using a detergent oil that is designed to keep contaminants in suspension for filtration may not be such a great idea for a non-filtered engine. The idea of non-detergent oil is to let contaminants settle into the sump. Link to comment Share on other sites More sharing options...
R.White Posted September 8, 2014 Share Posted September 8, 2014 (edited) I have read the dissertation with interest and come to the conclusion that the whole subject is a minefield (or should that be oilfield:confused:). The assertion that high detergent synthetic oils may be suitable for splash fed engines has come as a surprise - even a shock - to me. The researcher has been referring to a Corvair engine which is a relatively modern pressure fed unit. If one combines a modern oil filter with a low pressure pump I would fear the oil would never pass through it; being sent directly to the bearings via the bypass valve. BTW just because I am English doesn't mean that I don't know the difference between a Corvair and a Corvette. I know which I prefer!!Ray. Edited September 9, 2014 by R.White (see edit history) Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now