centaur gas engine

[Frank Boyle]

Hi all
I am about to make the main bearings.It states in the construction article that the bearings should be split is this necessary or could I use sleeve bearings instead as they would be easier to make.
Frank

[Jo]

It is not really necessary unless you intend on running it a lot as the split lets you take up any wear.

Jo

[Frank Boyle]

Hi Jo
Thanks for your prompt reply,I think I will make a sleeve bearing as I will not be running the engine much,that is if it will work.

[Ian S C]

Frank, the split bearings are helpful if you need to disassemble the motor without taking the flywheel off.  To make them, the two halves are soldered(Soft solder) together, and treated as a solid bearing, then heated to separate them.
I normally build hot air engines, and use ball bearings,  but I have rebuilt a Stuart Turner S9 which has split bearings.

[Alyn Foundry]

Dear Frank.

May I make an observation regarding main and big end bearings?

My RLE engine has done 1000's of hours running at steam rallies and is now on its third crankshaft. I have discovered that Bronze, unless copiously lubricated actually wears out the Steel very quickly.

I found that my Robinson X who's main bearings are Cast Iron ( as originally done ) no appreciable wear has occurred with similar running length of time.

As an experiment I made a Steel die and cast some Zinc alloy mains for the original half scale Gardner, the full size engine's used White metal ( Babbit ). This material has worked really well, virtually zero crankshaft wear the bearing material also within useable limits.

I too made the main bearings tubular to save quite a bit of time and effort.

Kind regards, Graham.

[Jasonb]

I usually make mine split but leave them soldered that way they don't get mixed up and the facility to adjust is always there.

J

[Frank Boyle]

Hi all
A lot of useful information which has helped me to decide how to proceed,thanks .
Frank