Originally Posted by
franchi
Hi Chris:
Thanks for the great reply.
I did not suggest that kerosene is a substitute oil. It aids in lubrication. I have been told that the longer life of a Diesel engine vs. a gasoline engine is due to the fact that Diesel fuel has a bit of lubricity where the gasoline does not. Gasoline may be thought as a solvent and the kerosene a light lubricant. With the added lube properties provided via the kerosene is 20% oil adequate for a Diesel engine? What are your thoughts about using a 50-50 mix of castor and synthetic oil for lubrication? It has been suggested that this mix will lube well BUT keep your engine free from built up deposits. Of course, these deposits may be a good feature for lapped engines. I know that I have never burned up a glow engine when 100% castor was used for oil!!!!
You are correct that I have never read the PAW instructions. I have never seen a PAW engine in my life as they are not popular in this country. As a matter of fact, Diesel engines never caught on in this country. I have read and collected many formulae regarding fuel mixes for model Diesel engines. There is a vey wide range for the proportions of ingredients listed. My Diesel advisor is a chap who spent his younger life ,34, years living in the Ukraine where he used Diesel engines a great deal. A chap in our club who grew up in South Africa and I are the only Diesel aficionados in the area. We both find them enticing and fun to use. Anybody can run a glow engine but it takes a MAN to run a Diesel! Lol
Again thanks for taking the time to reply to my post.
Be well my friend,
Franchi
Franchi-I find some of your comment odd-PAW engines are the most widely sold diesels in the US-and have had very good support and promotion by the US agent Eric Clutton. I can accept that you have not personally handled one-but your statement that they are not popular in the US simply doesn't add up-as any routine persusal of Ebay will confirm.I am aware that diesels have only minority takeup by modellers in the US-you might also reflect that this is not the case in other traditional modelling countries-by implication means those of us elsewhere may well have a lot more experience with them. PAW are simply the largest diesel manufacturer in the world-both numerically and in terms of range-not only that-they've been in business making diesels for well over 60 years I would seriously suggest that if they specifically caution against excess kerosene /paraffin)-they have a damn good reason for making such a statement! In any case-the only valid comparison is with glow engines-which use lubricant in a similar proportion. We have long since surpassed classical 'model' gas engines both technically and metallurgically (ie those using a 3/1 or 4/1 petroil mix)-and modern model gas engines are using much lower lubrication levels as well as often having structural refinements-needle bearing big ends for example-which are absent in our model diesels.
20% lubricant is generally considered a good safe level for twin BB engines-plain bearing ones are generally considered better off on 25%. It need not be overstated that 1/3 lube is excessive....but 1/3-1/3-1/3 mix has the advantage of being easy to mix-and no model engine ever suffered harm from too much lubricant-whereas the converse does not hold! I know of a few people who are using as little as 15% lube-equally i know these people have a lot of experience, know their engines inside out-and are very good at setting them. [and these people are generally flying team race and using engines that are cutting edge metallurgy-a lot more exotic than your traditional steel cylinder-cast iron piston, unbushed rod and plain crankshaft setup...] Horses for courses as they say...!
ChrisM
'ffkiwi'