I need some info about breaking-in car engines. I have an OS 12 CV, 15 CV-R and 18 CV-R that needs break in. I know people often break them in in the car, but also there are some break in stands specifically made for car engine on the market. However these stands needs a SG crank. My questions is... Is it possible to use a break in stand made for airplane engines to break in those car engines? And if yes, what size props should be used?


I have broken in at least 50-60 airplane engines in the last 20 years using "normal" break in stands, so I'm familiar with the safety issues. However I'm just wondering if there would be anything that would make break in of car engine unsafe to do in a stand. That would be much easier than swapping engines in my car ( I only have one car).

If you can mount a prop on it... go for a 8-4

Otherwise, should be the same as a ABC airplane engine.

As Jim said, if you can mount a prop on it then an engine is an engine. I don't think the huge heat sink head will cause any problem either because the heat won't have much chance to travel very far up it before it's cooled to a point it's not working anymore. For the .12 I'd try a 7x6 prop, an 8x4 for the .15 and maybe an 8x6 for the .18 (or thereabouts). You won't be able to use the car muffler though.

That said, my son broke in his .28 car engine by running it around a field for a few tanks starting at a 4 stroke and gradually leaning it out (flame suit on ).

Hi!
Ofcourse it could be done...but why ??? When it's so easy to just set the high speed needle a little rich and run the engine in the car ...as it is.

But if you do want to run them in using a bench try to use a small prop as those are high reving engines.
6x5, 7x4 or 7x5 would be fine (8x6 is too big). Naturally APC.