flyrotary@lancaironline.net Mailing List Archive

I first read about the limits on liquids for the Rotary in the Racing Beat Technical Catalog at least as far back as 1992 when I first received one. The limits cited were 210F on the oil (after the cooler) and 180F on the coolant (as it left the engine). These limits were apparently set for the older models of the engine and apparently were fairly critical for those blocks (pre 1986). Changes in the casting and passages since then appear to have given a bit more grace with temperatures.

I, Tracy and a number of folks have hit 240F on the oil for short periods 3 - 5minutes (in my case) with no apparently harm to the engine. I also have hit 220F with the coolant again with no immediate adverse affects (who can say long term).

I personally like for my oil to not exceed 220F and coolant to stay at 210F or lower for the climbout on a hot day. Cooler days sees around 200F for both on high power climbout. Cruise 175-180F.

All depends on OAT as that can shift the temps dramatically.

Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC

----- Original Message -----

From: Steve Brooks

To: Rotary motors in aircraft

Sent: Wednesday, July 14, 2004 1:51 PM

Subject: [FlyRotary] Re: New Scoop

Al,

Thanks for shedding some light on it. Both reasons make sense, and I was probably told why to star6t with, but didn’t remember.

Steve

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On Behalf Of Al Gietzen
Sent: Wednesday, July 14, 2004 12:53 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: New Scoop

Subject: [FlyRotary] Re: New Scoop

Kelly,

I would tend to agree, but according to information I received from other on this group, I was told that the common practice was to measure the coolant at its hottest point, and oil at it’s coolest point.

It’s logical place to measure the coolant at its hottest point since that is its limiting value. If you have coolant exceeding the boiling point anywhere (except for the nucleate boiling at internal surfaces) you have a problem.

The limiting factor on the oil temp in the rotary is its ability to cool the rotors/seals, so it’s the temp at which it returns to the engine. This limit is generally accepted to be about 220F, but could be exceeded some for short periods and probably not be a problem. The limit on the oil itself (breakdown) is higher; considerably higher for synthetics.

At least that’s my take on it.

Al