F14

Hi all,
I bought two .91 VRDF years ago (in the meantime I stopped all my rc activities) and now I wish to do the first run. can you give me some good procedures ?
I'll use them with Ramtec fans.
Many thanks in advance
Best regards

Angelo

Bax

My Feedback: (11)

You can download the instructions from:

http://www.osengines.com/manuals/65-91vr-df-manual.pdf

Basically, you take a strong, 12-inch prop, cut it down to about 10-inches or so, and bench-run the engine. Be sure your fuel has about 22%-23% oil content, at a minimum. Lower-oil fuels will allow the rod to seize to the crank almost immediately after starting.

F14

Bill,
thanks for your reply!
I've read the manual but I'm not sure about the prop.
First, why not buy directly a 10-inches prop ?
Second, ok for a 12 but which type ? 12/8, 12/10 or what ?
I know, maybe those are stupid questions but I really haven't the answers!
Thanks again!
Best regards

Angelo

Bax

My Feedback: (11)

O.S. states that you should use a 12" propeller cut down to 10". That's because the 12" prop will have a larger hub and larger blades. They would be stronger than a 10" propeller. Use a WOOD propeller. Wood props can be safely cut down. It's not a good idea with composite props. You can use one with a 6" or 8" pitch. You want to target the RPM range in the instructions.

F14

thanks Bill,
now I know what I've to do!
Thanks again!
Best regards

Angelo