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RPM stay out zone

sglynn

Well Known Member
I have the YIO-360-M1B and Hartzell CS Prop that you buy thru Vans on my 7A. Am I suppose to have a stay-out zone on RPMs between 2150 - 2350 where continuous use is not advised? Or a "yellow" stay out zone?

I've seen this in other POH's but I can't verify it is necessary. If true is this a attribute of the engine/prop combo? Or use of this engine/prop on an RV7A?

Thanks for clarifications.
 
Steve, the RPM zone changes with product changes, so it would be best to get this from Hartzell for your (prop) serial number and engine model. Compression ratio, timing etc can make a difference.
 
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Steve, the RPM zone changes with product changes, so it would be best to get this from Hartzell for your serial number and engine model. Compression ratio, timing etc can make a difference.

Bill is correct. It's an RPM range where the Hartzell engineers have noted excessive vibration. However, it can change from other factors.

For example, I have the same engine and prop as you. Based on the engine, prop, and hub model and serial numbers, the Hartzell folks gave me the same avoidance range.

Now, however, with the addition of two PMags, they want me to avoid 2000-2250 for extended operations. I folded these into my POH and adjusted the green and yellow bands in my Skyview EMS.

Give the Hartzell folks a call: They'll send you a great email reply. I printed mine and filed it in my engine's and prop's documentation.
 
What blades are on your Hartzell prop? The TCDS should have most of the info you are looking for.

Different blades have different RPM yellow zones.

The old F7666 blades have a yellow zone to avoid continuous operation
between 2000 and 2350 RPM.

The F7496 blade also have some limitations. I think there was a time limit at 2700 RPM only for takeoff plus some manifold restrictions in addition to other limitations.

The F7497 blade was the most desirable blade but I do not remember what if any limitations existed.

Most of the Hartzell metal props had limits when using higher compression pistons and electronic ignition.
 
Vans IO360-M1B and Hartzel

Conclusion:
I did submit inquiry to Hartzell and received quick email reply say, "No restrictions for the 180HP YIO360-M1B with HC-C2YR-1BFP prop on my RV. I

And the Application Manual 159 (shared on this thread earlier) verifies this to be true also. So great, for those who bought "standard" IO360 engine and CS prop combo from Vans there are no RPM restrictions.

Thanks for the help.
 
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