making of diesel engine

It is not possible. Your bike will blow up.

It would perhaps be possible with swap in of a small diesel one lunger, but the way he is headed would NOT work out well, I agree.

Normally diesel one lung engines are heavy as billyhell, so unless he could find something, surplus, really small and light, he should go back to bed and try for a different dream.

Taking this a little further, some of the Yanmar diesel engines are rather light in weight (100 lbs and less), and put out several horsepower. So it isnt impossible.....but maybe economically unfeasible unless you can find a used engine.

Interesting. Two different ways to interpret the orig post. :) I thought the poster was wanting to convert his gas engine to diesel. You may be thinking he wants to swap engines entirely. That could be done relatively easily, although it may be expensive.

When I saw his original, and your answer (with which I totally agree), it seemed that there were not many ways to get to where he wants to go.

I really see no reason to make such a change. Even with gasoline at the price of Jack Daniels, this conversion will probably not pay off.

for a small lightweight engine like this, there's almost nothing that can be re-used in any kind of diesel conversion. the cylinder head needs to be replaced to give you the compression ratio you need, the piston needs to be changed to give you the combustion pattern you need, the connecting rod won't be strong enough, the crank probably isn't strong enough, and the flywheel needs to be significantly heavier to provide the energy to not stop during the compression stroke at idle. then you have the issues of higher loads on the bearings and lubrication system, and also cooling.

bottom line, as others have said, you're better advised to find yourself an appropriate diesel engine and retrofit the motor cycle with that than consider any kind of "conversion" of the existing. many people have retrofitted their motorcycles with diesel engines, and you can find many examples on the web to give you ideas and inspiration.

Maybe he needs one of these:

Or maybe this one is not quite so ambitious

The main problem is that you need a lot higher compression ratio, and that means reducing the size of the combustion chamber in the head and putting in much more rugged valves.

In the 1970s when gasoline became expensive in the US, Oldsmobile took an existing gasoline engine and re-engineered it with a new head for use with diesel. However, because they were using the same block and basically the same head design, it was not sufficiently reinforced to handle the higher pressures needed for diesel operation and they failed pretty severely after a fairly short amount of time. A lot of mechanics made good money converting them back to gasoline.

Diesel, in fact, isn't a very good choice for a small light engine for something like a motorcycle, just because of the amount of reinforcement that is needed to make it run reliably.

--scott

I content that such an engine could be made fairly cheaply IF there were the demand for it.

snipped-for-privacy@panix.com (Scott Dorsey) wrote in news:jmhm1r$rgk$ snipped-for-privacy@panix2.panix.com:

One of the Hemmings publications had an article on the '70s Olds diesel about a year ago. According to the author, the block and heads were NOT the same as the gasoline ones, but had been modified to handle the higher pressures of diesel use.

As I recall from the article, the problem with the Olds diesel stemmed from the fact that they /chained/ the fuel pump to the engine instead of using /gears/. As the chain stretched over time, fuel-timing changed as well, and this caused all sorts of driveability problems.

This is true. Unfortunately, they weren't modified enough.

Yes, but this was only one of many, many problems with that engine.

--scott

Zoche is trying! And the Junkers folks did successfully make reciprocating diesel engines for aircraft during the war.

--scott

About 20 years ago I knew a mechanic who claimed to have figured out what was wrong with the "GM gas engine converted to Diesel". He said that they changed the heads, but used the same head bolts. The old bolts were either 2 threads too long or 2 threads too short, I don't remember. This caused everything from cracks in the head due to hotspots, blown head gaskets, ring failure, bottom-end failure, etc. He had a big long yarn that he would tell about it, ending with the part where he sent a letter to GM but was ignored.

I didn't put a lot of stock in the story myself, but it was always fun to hear.

-J