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My makeshift Onan Heat Shield [message #262348] Fri, 19 September 2014 21:25 Go to next message
Ken Burton is currently offline  Ken Burton   United States
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http://www.gmcmhphotos.com/photos/g6681-onan-heat-shield.html

This is not as elegant as Kerry's or Wally's but it has done the job. I will be definitely getting one of Kerry's sometime in the future after Kerry gets his design and production finalized.

I posted this weeks late but promised Kerry I would do it.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: My makeshift Onan Heat Shield [message #262356 is a reply to message #262348] Sat, 20 September 2014 00:11 Go to previous messageGo to next message
Chr$ is currently offline  Chr$   United States
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Nice.

-Chr$: Perpetual SmartAss
Scottsdale, AZ

77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"

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Re: My makeshift Onan Heat Shield [message #262359 is a reply to message #262356] Sat, 20 September 2014 07:11 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Functional, yes. Nice, no.

This is why I asked Kerry to make us some professional ones.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: My makeshift Onan Heat Shield [message #262387 is a reply to message #262359] Sat, 20 September 2014 12:15 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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There is not a lot of room above the Onan and a heat shield works by having air moving on both sides of it. More air is better. When the shield is low enough for air to move across the top, it is close to the manifold and reflecting heat back at it making it even hotter. So it needs air moving under the shield to prevent that, and air is moving under the shield is reduced because it is restricted by its proximity to the manifold. A tightrope of sorts.

All of the heat shields I have seen in thread activity here in the past few days are too big. I saw one once that only covered the manifold plus a little more that I think would work better than the ones I have seen here lately, but I can't find a picture.

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Re: My makeshift Onan Heat Shield [message #262430 is a reply to message #262387] Sat, 20 September 2014 21:51 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Wally had an interesting one. Did you look at his?

One thing to consider is the burn spot on mine is a little larger than a softball. With Kerry's shield, some of that heat is reflected back at the manifold but some of that heat is also absorbed by the aluminum shield and conducted away like a giant heat sink. In this case a larger shield and heat sink might be better.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

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Re: My makeshift Onan Heat Shield [message #262552 is a reply to message #262430] Mon, 22 September 2014 18:59 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Ken Burton wrote on Sat, 20 September 2014 21:51
Wally had an interesting one. Did you look at his?...
That's the one I had in mind. From this view it looks good:
http://www.gmcmhphotos.com/photos/data/6254/medium/shroud_hole_2.jpg
But from this view it blocks too much air:
http://www.gmcmhphotos.com/photos/data/3841/841_p18194.jpg

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Re: My makeshift Onan Heat Shield [message #262597 is a reply to message #262552] Tue, 23 September 2014 00:59 Go to previous message
djeffers is currently offline  djeffers   United States
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I like the way Wally's is quite open, yet covers the exhaust manifold and agree that it could be more open on the forward back side.

Looking good.

Don & Susan Jeffers
78 Eleganza II

[Updated on: Tue, 23 September 2014 01:01]

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