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Cowl removal

Capt

Well Known Member
Ok guys I've recently bought an RV8 & now I would like to learn how to remove the top cowl for a start. It's built as per Vans plans. Can someone give me an idea step by step to removing these wires/pins for removal then reverse for fitting the cowl?
The lower cowl I'll look at another time.

Thanks.
 
My sequence is:

1) Open the oil door and remove two hinge pins on top of firewall. These pins run along the top of the cowl\firewall joint and are curved. (Hinges meet off center on top of the firewall with joining point between the two pins being skewed to passenger side.)

2) Pull both pins (left & right side horizontal pins) that join the top & bottom cowl. Pull out by front propeller

Remove Top Cowl

For Bottom cowl

3) I then remove two small (8 inch) horizontal hinge pins located down by exhaust on bottom of firewall (Horizontal joint between firewall and bottom cowl)

4) Remove two vertical pins located on the firewall on left & right side of bottom cowl.

5) Carefully while holding cowl in place, remove my air intake and then lower cowl.


There are multiple methods for securing\covering access to the hinge pins so I cannot comment on how to gain access to the ends of the pins. Mine is a simple loop and I tie wrap it to secure in place.

I would suggest cleaning the pins and relubricating them every few months to allow for easy insertion.

Good luck and enjoy the 8
 
There are usually horizontal pins holding the top cowl onto the bottom cowl. If you can see a pin on the front sides of the cowl, remove the screw and pull the pin. Sometimes there is a decorative cover plate that must be removed. Some people insert the pins from inside the cabin, usually having a knob on the pin. If you pull them from there, make a note of when the pin releases the last eyelet and don?t pull it back further than that.

The pins between the top cowl and the firewall are usually accessed brought the Oil door. There are usually 2 pins, one holding the right hand third and the other holding the middle and left hand thirds. Just pull the sideways accordingly until they release. There will be a break in the hinge eyelets where the pins meet.
 
Thanks guys:) I know of the pins but have never moved them, I just wanted to check the process so to speak from those that are in the know, I guess once I have the cowls off I may regret I did it getting them back on:):):) Also thanks for the heads up on the cowl screws in the intakes.
I have put my hand in thru the oil door to feel for the pins & thought sheeez getting the one that slides towards myself started will be fun when replacing the top cowl! I saw a 7 recently that had cam locks all over it, I guess the owner had run out of hair to pull out !:)

Again thanks guys, I can't get the RV grin off my face but the cowls may remove it!:D
 
I can remove my entire "ALL PINS" cowl in about 10 minutes. Less than 5 for the top cowl only. I remove the horizontal pins first to relieve any tension on the more difficult firewall pins. The first several times might be painstaking until you learn the routine. If you have some tight pins, sand them with emery cloth, clean them, and then lubricate them with Boe Lube every time you reinstall them. If they were installed right, you will be surprised how fast and easy it is!
 
My brother showed me a technique of running painters blue tape on the fuselage, landing gear and spinner around the cowl pieces that will be removed. This prevents damaging paint if the cowl hits these surfaces while removing or installing. I do it every time.
 
Went to the hangar today to pull the cowls off, reached in thru the oil door and couldn't move the top pins, not even a millimetre !! Thought best leave it for now, might look at cam locks at the next service like I saw recently on a 7, happy owner I'd say!👍
 
Went to the hangar today to pull the cowls off, reached in thru the oil door and couldn't move the top pins, not even a millimetre !! Thought best leave it for now, might look at cam locks at the next service like I saw recently on a 7, happy owner I'd say!👍

Perhaps you are trying to push the pins in, not pull them out - or you have not got them unlocked from whatever pin retainer the builder made. Put your phone in the oil door and take a photo to see what is going on. Once you get them out, add a drop of oil on the pins to make it easier next time. Just a drop!

You?ll figure it out. Don?t mess it up with cam locks.

Carl
 
Can you still get ahold of the person that sold you the plane? If you can, get with them for an hour to learn how they did simple tasks like this - no two planes are identical, and builders all have their little secrets.

This is important for anyone purchasing a homebuilt - make sure to get a “complete” checkout - and not just on the flying qualities.
 
Perhaps you are trying to push the pins in, not pull them out - or you have not got them unlocked from whatever pin retainer the builder made. Put your phone in the oil door and take a photo to see what is going on. Once you get them out, add a drop of oil on the pins to make it easier next time. Just a drop!

You?ll figure it out. Don?t mess it up with cam locks.

Carl

Am pulling not pushing, there's no pin retainers, the ends which are rather long and have a rough 90deg bend on them are hanging out in the breeze. Upon closer inspection they have several marks on them, looks like they have been handled with pliers.
 
Paul the aircraft was checked out completely by the engineer and myself but not de-cowling due to time constraints. The previous owner never touched the plane maint wise, he had the same engineer for 16 years. I won't be bothering him anyway, he only sold due serious medical issues and I respect his privacy.
 
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Paul the aircraft was checked out completely by the engineer and myself but not de-cowling due to time constraints. The previous owner never touched the plane maint wise, he had the same engineer for 16 years. I won't be bothering him anyway, he only sold due serious medical issues and I respect his privacy.

OK - I get that you don;t want to bother the previous owner. But I have to tell you I am surprised that you?d think that the engineer (that?s your word for a mechanic...right?) checked out the aircraft ?completely? without removing the cowling. Half the things that go wrong with airplanes are under the cowl - so if you haven;t looked under there, I?d suggest that you find a local RV owner/builder that can help you get teh cowl off and see what you?ve got.
 
The engineer(mechanic in yr world) knows the a/c thoroughly as he has maintained it for the last 16 years in a row so yes was checked out thoroughly over time. It had not flown since he last completed the annual inspection so removing the cowls at the time I was checking it out wasn't needed nor did he have the time on the day. Anyway that's getting off track with what I'm trying to learn here, cowl removal and which way to hold ones tongue whilst cussing !!
 
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Am pulling not pushing, there's no pin retainers, the ends which are rather long and have a rough 90deg bend on them are hanging out in the breeze. Upon closer inspection they have several marks on them, looks like they have been handled with pliers.

My -4 was completed in 1991 and has around 1100 hours on it. I still have to use Vice Grip (locking) pliers whenever I remove/replace the pins. On a friend's -8, he (an OCD hobbyist machinist) threaded the ends of the side pins (unreachable when fully inserted) and made a female-threaded adapter to capture them so he could pull them. The top port side pin he left long enough to chuck in a drill, so he could spin it in and out.

Point being, if they slide in and out with zero effort, it's either absolutely perfect, or the fitment is way too loose. (2nd one would be way more likely.)

Grab it with a pair of Vice Grips , or chuck it in a cordless drill.

Charlie
 
For what its worth on my 6 i have best luck standing on a sturdy stool seems to give me a better angle to reach in and pull the pins and install them
 
Finally got my cowls off today for the first time since I bought the beast, now I know why I've seen a few with screws all round! I'd hate to be doing that on a reg basis, thank Christ I had a mate give me a hand. The bottom cowl was easy with another pair of hands the top cowl however is another matter ! lots of lube on the wire/hinge to put them back, doubt I'll be pulling them again anytime soon!
 
Could you try pins from wire a little smaller in dia? If that doesn’t help, I would change to screws and nut plates or cam fasteners. If you can go with smaller wire, be sure it is secured so that it won’t work out. The cowl needs to be easy to remove because you should look under there often. Check for leaks, fluid and exhaust, chaffed wires, alternator belt, engine mount cracks and others.
 
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Yes I understand re looking under the hood, have owned a few planes now over years but this is my first where it's a pain in the butt! Fortunately it's very clean under the hood on this 8, lots of $$$$ spent on this bird! I can see why paint gets chipped off at the cowl edges, not the smartest idea I've seen for cowl mounting.
I will see if I can get some smaller diam wire. & put a point on the ends.
 
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