Replies to This Discussion

Permalink Reply by Robert Riat on July 26, 2019 at 11:31am

I have a UL engine and Lithium battery mounted on the engine side of the firewall for 15 months and 110 hours with no issues.  Can’t answer your question about the temps in that area, but I did have high oil temps last summer until I changed to the larger cooler this Spring when I did the condition annual.  I have the stol 750 and Roger (at Zenith) sold me the battery and didn’t say anything negative about mounting it there.

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Permalink Reply by Jim and Amelia Isaacs on July 26, 2019 at 6:54pm

Spend a bit more and buy a lithium battery designed for aircraft with integrated health monitoring and under/over voltage control circuitry, and don’t worry about a given ambient temp. I chose EarthX for my 701 for these and other safety features. 

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Permalink Reply by David J. Beaulieu on July 26, 2019 at 6:58pm

Ralph...see this post

http://www.zenith.aero/forum/topics/100-hr-engine-service-etc?xg_so...

Dave

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Permalink Reply by Damon Brantley on July 26, 2019 at 9:42pm

I would think it would not be too hard to setup a thermocouple in the engine compartment to monitor the temperature.

A lot multimeters come with thermocouple reading ability. You could temporarily mount a probe in the engine compartment, hook up the meter and do a test flight.

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Permalink Reply by Larry W. Sward on July 27, 2019 at 4:14am

Another option is to get the temperature dot sticker that stick on from McMaster Carr. They come in various temperature ranges with 5 dots per sticker. Typically about $2/sticker when a temperature is reached, the dot changes from silver to black and stays black so you can land, shut down and then open the cowl and determine the max temperature that was reached inside the cowl, can stick directly on a battery case.

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Permalink Reply by Ralph Powell on July 27, 2019 at 10:12am

Larry,

See link from David above, that is what he did. I am confident that the engine compartment temps are below EarthX max operating temps, however, lithium batteries last a lot longer when use is restricted to room temperature. Based on David’s temps I may relocate it to cabin side of firewall. Or if it turns out to be a major pain leave it where it is and deal with a shorter battery life.

Thank you all for your useful and prompt feedback,

Ralph

N750RP

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Permalink Reply by John Austin on July 28, 2019 at 7:47am

I flew my EarthX on the engine side of the firewall without problems for quite some time. Later, however, I was "cleaning up" the firewall while re-routing a fuel line and decided to re-locate the battery to the cabin side of the firewall.  Fortunately, I was able to utilize the same mounting holes for the battery box, making the re-location quick and easy - now that's lucky!  ;>)

John

N750A

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Permalink Reply by Leo Hicker on August 1, 2019 at 11:56am

I talked to earth-X before mounting mine engine-side, they said I should be fine.

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Permalink Reply by Ken Ryan on August 1, 2019 at 5:24pm

Another option is to build a blast box (a shroud with an air inlet) to ensure cool temps.

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Permalink Reply by David Gallagher on August 5, 2019 at 8:09am

Ralph,

I put a thermocouple near the firewall of my 601XL to answer this very question and to act as a fire detector of sorts.  It is located about even with the top of the engine by the nose gear strut top.  I consistently see temperatures about 30 degrees above ambient temp during cruise flight.  Not sure how this would relate to the 750 Cruzer, but it is probably pretty close.

Dave G.

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