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By thegasguy
#1507933
All the aircraft in our open-fronted hangar were literally dripping with moisture when I went to get mine out today.
I'm concerned about such moist air making its way via the short open exhaust pipes, into whichever cylinder has the exhaust valve open. I figure the oily filter and carb butterfly on the inlet provides some protection that side.
Is there a position ( C90-14F) that leaves all valves closed? Or at the very least, all exhaust valves?
I could then always position the prop appropriately.
I'd "bag" the exhausts but they stay hot a while and I'd hate to melt anything onto them.
By cockney steve
FLYER Club Member  FLYER Club Member
#1507999
You will always have one exhaust and one inlet open.....IN THEORY.....Given it's a 4-cylinder, 4-stroke engine and given the objective of a smooth power-delivery, it follows that at any one time, each cylinder will be on a different stroke....however, valve -timing overlap means that valves stay open longer than the 180* crankshaft -rotation of a stroke...........squirt a bit of WD40 up the exhaust, followed by a plug of bright-coloured COTTON cloth with a gooodly "tail" hanging down.
#1508023
Sounds like good advice, although I went and fitted those silencers from Air world that are closed off pipes with many holes in the side. I can't remember the name of them ? Is it "Ilmer silencers"?
This will make them impossible to stuff, which is where the bagging idea originated.
I think I will somehow make 2 fire-proof ( just in case) bags that slip on and follow your advice of a squirt of WD 40 ,as best as I can aim it, up the pipe.
I use flame proof mats at work, for soldering on - they are sort of fabric-ish and about the right size.
Looks like I'm off to Screwfix !
By cockney steve
FLYER Club Member  FLYER Club Member
#1508073
Think you'll find they are woven fibreglass mat.(soldering-mats) but I don't know how the edges are sealed.....presumably, someone, somewhere is making a fireproof thread to stitch the edges.....Nomex ?
try googling "Fibreglass supplies UK".........I suspect it won't be durable enough on it's own and, of course, it's extremely porous. you could try "curtainsider material" , " vinyl lorry tarpaulin material " and variations........this is usually sold in 1.5 metre wide rolls usually fire-resistant, self-extinguishing grade as standard. It's also used by Bouncy-Castle makers and soft-play centres. As it's waterproof, would be ideal for exhaust-muffs with or without a fibreglass lining.

@ AK7274.....think you'll find it leaves behind a water-repellent film certainly works on bare steel panels I'm piecing-in on a range-rover. garage has high humidity (OK, it's a barn! )
There are probably better inhibitors on the market but WD is a quick, cheap, readily available kludge.
#1508101
I'm happy with WD 40, anything better like ACF50 is too expensive per shot.
We need to remember it's going to be shot out on fire later as well ! Anything wax based just might stick to the fabric and burn.
The plastic material ' sleeves' sound good, as long as I allow some cool down time, it turns out the burn mats are too small anyway.
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By Flying_john
FLYER Club Member  FLYER Club Member
#1508136
Of course the real answer is to do loads more flying and not give the condesention time to form.

But seriously, If you start blocking orifices, thats fine to stop birdies nesting etc, but airflow around the aircraft and engine is good, as it will self dry with airflow. If you start blocking things up, without any dessicant, then the moist air will stay and condense and not be able to evaporate once conditions change.
GrahamB liked this
By cockney steve
FLYER Club Member  FLYER Club Member
#1508171
^^^^^^^ a very good point, then consider the day -night warming-cooling cycle and the whole airframe and engine are constantly "breathing" air in and out....depositing condensation overnight, expanding duting the day, then "sucking in" cool, potentially moist air which will continue to cool........
Of course, you could have a heated hangar, or a cocoon!
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By Ben
#1509024
I wouldn't use WD40, first it doesn't sound right and second you will never cover all the insides of the engine. The cylinder is your secondary worry, the first is the camshaft.

the options are:
1. Use Silica Gel plugs instead of the engine plugs (1 per cyl.) and dry air pump.
Connect the outlet of a low pressure pump (if you have electric supply) to the engine breather and the intake to a box filled with Silica gel. Make sure that the box intake and outlet ports are at opposite sides, the intake at the bottom and the outlet at the top.

2. Use ASL Camguard. Will do wonders to the inside for about 21 days before you have to fly the engine. For oil recommendations look at ASL site.

Good luck
Flyin'Dutch' liked this
#1509320
Ben;
No reliable electricity supply that I can get easily to my aircraft, we all swap positions as we fly at different times.
I agree that your pump suggestion would be gold standard drying - out, but, it is not practical for me.
I was thinking that I could stop moisture getting in from outside through an open valve, I'd forgotten about moisture generated inside the running engine.
I usually fly for a minimum of an hour, I hope this boils off any water in the oil.
I'm very interested in Camguard, I know Lycomings need it - do Continentals benefit do you think?
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By Flyin'Dutch'
FLYER Club Member  FLYER Club Member
#1509499
mick w wrote:Pull it out once a fortnight , Chock it facing the Hangar & sit in it for 15 mns at full chat , & pretend your off somewhere for a quick jolly . :wink: :thumright:


Nope that doesn't do the job.

You need to fly it and do so for at least an hour to get the oil hot enough and hot enough for long enough to disperse (boil off) the water in the oil in the engine.

'Pulling the blades through', running the engine on the ground etc are all much more likely to do harm than good.

If you cannot fly for a prolonged period of time inhibit the engine by all means properly (change the oil to an inhibitor, take plugs out and plug up the intake and exhaust inlets/outlets) but all the rest is window dressing unlikely to do any good to engine.