Enya 90 4C Help
#1
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From: , WA
Hello,
Just recently got a hand me down, custom made plane with an Enya 90 4C engine. Engine needed some work (ie. blown head gasket, valve clearances and lubing) and I think I got it compressing enough to start. I have 2 main problems. Which way does the prop spin? When facing the planes, (prop first, tail far), and turn it clockwise, I get great compression and the prop springs back when I spin it, counter-clockwise I get less compression and very little spin back. From the few videos of people starting their planes I've found, it looks like they're all turning counter-clockwise???
Second, facing the plane again, and lookings at the rockers, is the intake valve on the left and the exhaust valve on the left?
I know these are very "no duh" questions for most of you.
Thanks!
Just recently got a hand me down, custom made plane with an Enya 90 4C engine. Engine needed some work (ie. blown head gasket, valve clearances and lubing) and I think I got it compressing enough to start. I have 2 main problems. Which way does the prop spin? When facing the planes, (prop first, tail far), and turn it clockwise, I get great compression and the prop springs back when I spin it, counter-clockwise I get less compression and very little spin back. From the few videos of people starting their planes I've found, it looks like they're all turning counter-clockwise???
Second, facing the plane again, and lookings at the rockers, is the intake valve on the left and the exhaust valve on the left?
I know these are very "no duh" questions for most of you.
Thanks!
#3
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What order should the valves open? When turning my prop counter-clockwise, exhaust opens followed soon by intake, full turn of prop, exhaust then intake, rinse repeat. Is it possible that my crank gears are backwards and hitting the rockers in reverse order?
#6
Exhaust should open first followed quickly by the intake.
An easy way to remember this is to think about how a 4 stroke engine works. As the piston comes up on the stroke that the valves open it will exhaust the burnt gasses on the way up (exhaust opens) when it gets to the top of the stroke the exhaust valve closes and the intake valve opens so that as the piston moves back down it will draw new fuel into the cylinder. The next time the piston comes up both valves stay closed so that the fuel compresses, when the piston gets to the top this time the fuel will burn forcing the piston back down, then up, exhaust, intake, compress, burn, ect....
PS: don't even try to mess with the gearing in the back, you will get the timing hopelessly out of wack very easily.
An easy way to remember this is to think about how a 4 stroke engine works. As the piston comes up on the stroke that the valves open it will exhaust the burnt gasses on the way up (exhaust opens) when it gets to the top of the stroke the exhaust valve closes and the intake valve opens so that as the piston moves back down it will draw new fuel into the cylinder. The next time the piston comes up both valves stay closed so that the fuel compresses, when the piston gets to the top this time the fuel will burn forcing the piston back down, then up, exhaust, intake, compress, burn, ect....
PS: don't even try to mess with the gearing in the back, you will get the timing hopelessly out of wack very easily.
#7
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From: , WA
Not worried about the cam gear timing, that's easy money. Enya's have marks on the cam gears and crank to help align them.
Is it possible that when I reconnected the crank back to the piston that the piston arm was facing / this way instead of \ that way, giving me compression in the wrong direction? Should be a realatively easy fix.
Is it possible that when I reconnected the crank back to the piston that the piston arm was facing / this way instead of \ that way, giving me compression in the wrong direction? Should be a realatively easy fix.
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From: Anderson, SC
Where can I get a user guide for a Enya 90-4C. A online one is okay. Please email me at [email protected]
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From: ChelmsfordEssex, UNITED KINGDOM
ORIGINAL: cougrocks
What order should the valves open? When turning my prop counter-clockwise, exhaust opens followed soon by intake, full turn of prop, exhaust then intake, rinse repeat. Is it possible that my crank gears are backwards and hitting the rockers in reverse order?
What order should the valves open? When turning my prop counter-clockwise, exhaust opens followed soon by intake, full turn of prop, exhaust then intake, rinse repeat. Is it possible that my crank gears are backwards and hitting the rockers in reverse order?




