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Looking for a few good plenum ideas

F1R

Well Known Member
I am considering fabricating a new Carbon or Fibreglass plenum.

Any photos and ideas are greatly appreciated.
Good sealing and rapid removal / install time are what I am looking for, to encourage and allow top side engine inspections more often.

So please post your photos.

Thanks in advance!
 
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Building my cooling plenum as I go. After considering some exotic layup options for the upper lid I finally said "f$&k it" and went with an ultra simple .016 aluminum flat wrap lid secured with piano hinge around the entire perimeter. Yep, it's flimsy in a static condition but I figure in service it will try to blow up like a ballon so it should not see any drumming which would lead to cracks. The piano hinge really spreads the load unlike the typical screw hold down and as a bonus should be pretty leak free. Between maintenance I envision a bit of speed tape here and there to seal the few leak paths.


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There are 6 pins in total and they take about 1 minute to remove or install. The plenum top just whips right off with no tools.

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The big remaining problem to solve is access for the oil dipstick. Some people build a cofferdam so the dipstick is always accessable, but that will kill plunum volume and be difficult to seal reliably. I'm thinking a sliding door or spring loaded doors in the plenum top for quick and leak free access. Still chewing on that one.
 
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A suggestion for the dipstick:
Get a 3” flange from acs, cut a three inch hole in the plenum,and rivet the flange under your plenum directly over the dipstick.
Remove dipstick assembly from engine. Make a “donut” from.032 or .040. ID the same as the dipstick tube thread. OD about 4”, you may have to trim in spots. Now get a piece of 3” scat about two or three inches longer the you need and fasten it to the flange with a hose clamp. Now when you put the lid on the 3” scat hose will seal against the donut. You may need to remove a bit of the spring to get it to seal. 1000 hours and counting.
 
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Thats pretty compelling Tom... How about adding another 3" flange to the "doughnut" so the SCAT has some tube to hang onto? Good stuff!
 
N14ZM has more or less standard baffles made mostly from RV10 components. It?s always run cool and it?s very easy to service. Might not be the most efficient but I like simple :)
 
Any Photos of N14ZM ?

I am curious how close your spinner sits to the cowl? I have often thought about switching to the conventional baffles and seal route, but in a couple places my spinner is less than .050" to the cowl. There are no rub marks as is and I am reluctant to add the upward pressure un the underside of the top cowl.

My plenum cools well enough, the only down side is the time involved to access, inspect and service the top side of the engine.
 
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