The trouble started on the way home. We departed New Holstein at 7AM for an uneventful arrival in OSH and parked in post-war boom planes and made it over to hear Bill Rusk talk about the ins and outs of building an experimental supercub in the Homebuilder Hangar. Departed by 11AM west bound and made it 3 hours west to this awesome little spot in Minnesota - Rushford, MN - great airport by the way - nice grass apron to land on, showers, free burgers and a a very pretty spot on a ridge in the hills. Shot the shit with a couple of the hangar rats, and after an hour went to move on.
Since the J3 was still warm, I switched on the mags and hand propped her normally and she fired on the first go - like she most always does. This time around, somethin ain't right. Vibrations, weird loping, ran really rough. Oh no. I run her up and do a mag check - which had higher than normal rpm drop - but still only about 75 rpm - so that wasn't too bad. Taxied out to the runway to give her a go. Throttle up - something had shit the bed - won't make full power and max rpm is only about 1700 (normally about 2350 is takeoff rpm). I aborted the takeoff and taxied back to the ramp.
Once shut down - I get out and pull the prop through. Once - okay. Second time - okay. Third time - hey that ain't right and the prop swings through a full rotation. Hmm. 1 jug isn't making compression. But which one? I start pulling spark plugs. Put a thumb over the hole as you pull through - you should get 3 that suck in - and 1 that pushes out. If you don't get a good push - that's the jug that isn't making compression. Mine was #4.
I pull the rocker cover, and sure enough. #4 cylinder exhaust valve is stuck open (compressed). This is not what you want to see:
Great, now what? We're in a little airport in the middle of nowhere - and everybody who is anybody is 200 miles away at Oshkosh. Fortunately we'd just been pounding beers around a camp fire with a salty lot of cub pilots. I was in the back listening and taking it in - but obviously not enough - talk of the rope trick. I remember hearing about it - but didn't fully understand what it would (could) be used for. But hell, I can't walk back to Colorado - so between myself, a fellow PA-12 driver who was travelling along the same route and a couple of the hangar rats - with some phone in instructions from more senior and well traveled aviators pieced together the procedure. It goes something like this:
1 - get a beer - you're going to be here more than 8 hours and you will need something to cry in if this shit don't work
2 - get your tie downs - you do have tie downs don't you dipshit?
3 - shine a light in the spark plug hole and pull the prop through till the cylinder is bottom dead center - farthest away from the valve - maximum volume in the cylinder.
4 - push in about 10 times more rope than you think is necessary into the spark plug hole. Hope your rope is fairly clean and reasonably soft and try to keep it from getting under the valve
5 - turn the prop - pushing the rope and compressing it on the top of the valve - and hopefully push it back into the valve guide.
6 - If nothing happens - or the valve only partially comes out - pull the rope out and try again. you may need to pull the other spark plug and use safety wire or something to keep the rope from getting under the valve and preventing it from pushing in. Pull the rope and go back to #4. Mine took almost 15ft of rope in the cylinder - more than you think it will take.
Voila! Wait - i just started drinking beer? Can't I go fly it now? No bueno compadre - that puppy is VERY likely going to stick again as soon as you pull through. Don't believe me? Wait don't try it yet - you'll get your chance soon enough. This is time for another trick:
"Staking" the valve: You need a hammer and a block of wood. And some Marvel Mystery Oil or some kind of oil and something to squirt it as far into the valve guide as you can - which won't be very far. Put the block of wood on the rocker arm, and give the valve some whacks - if it sticks - use the rope trick to push it in and out. You're going to be doing this a bunch of times - trying to clean off whatever gunk is built up on the valve stem or in the guide. Maybe, just maybe if you hold your tongue right and the stars and moon are aligned - this will get it freed up enough. It's doubtful - but you might get lucky. Spray Marvel Mystery oil in the valve guide, in the air box, put some in the fuel - and more in the oil - anything you can think of to get more lube in the induction system. Do a stuck valve dance - it's pretty similar to a rain dance. Pray to your maker.
Now if you can get it to stay unstuck while you pull her through on the prop - you might be lucky enough to get it started. Me? No joy. That shit is stuck like the grizzly's winter butt plug. She ain't movin!
Now it's time to get serious. Survey your inventory of available tools and expletives - cause you are very likely going to need some you ain't got. Well, I had plenty of expletives - but the only tools I had were a hatchet and a block of wood. After raiding hangars and getting help from more salty dogs I wrangled up some more required tools:
1 - dental floss - hygiene is important - but not as important as this stuff - and no a toothpick ain't gonna cut it
2 - valve spring compressor - what you say? a J3- driver doesn't travel with a valve spring compressor tool in your emergency tool kit - SOL
3 - 1/4" coarse thread eye bolts or
4 - a piece of bar stock and a drill
5 - 2 large screwdrivers
6 - Safety wire, coat hanger, grabber tools, magnets anything you can find that is useful for fishing
7 - Scotch brite pads
8 - Marvel Mystery Oil - I put that shit on everything
What the hell is this shit you say? Dental floss? You must be out of your mind! What the hell are you going to unstick an exhaust valve with dental floss? Pay attention grasshopper - skool is about to be in session.
Now shit's about to get real. You gotta remove the springs and the rocker arms. So if you have no valve spring compression tool - you gotta MacGyver something up. Hopefully you are smarter than I and travel with 2 eye bolts that you can screw into the rocker cover bolt holes and fashion 2 screwdrivers through to get leverage to press down the springs and remove the keepers. Careful of your fingers. No eye bolts? Take bar stock and use the valve cover as a template - and make a bar that will go across the bolts that you can use to get the screwdrivers under to press down the springs. Take the exhaust springs out - and don't drop and lose the keepers. Usually it's the exhaust valve that sticks because the intake is closed during combustion. Tap out the bar that holds the rockers on. Don't mix them up - you'll need to reassemble this thing sometime if you want to fly it out of the hole you are in.
Now you should be staring at a stuck valve. Get your dental floss. Tie a beautiful fly fishing knot around the end of the valve stem. Or just tie a lot of knots. But not too many. It can't be bulky. Now with a tap or screwdriver, or something - gently start tapping the valve into the cylinder. Yes - ALL the way into the cylinder! But, but, but... How will the engine run? Patience grasshopper.
Use safety wire or whatever to fish the dental floss out of the top spark plug hole. Now pull the valve stem out. The valve can't come all the way out cause it's too big for the spark plug hole - but you should be able to access a LOT more of the valve than you can through it's valve guide. Get your mystery oil and scotchbrite pad - and clean the gunk off the valve stem until it's shiny as a whistle. Use what you got. Careful not to score or damage the valve - but if all you have is a knife and no scotchbrite - it's better than rotting on the side of the AlCan waiting for winter or the Alaskan state bird to suck you dry from the inside out. Also you're going to need to clean out the inside of the valve guide. What's that - you did remember to put the right size reamer in your emergency tool kit right? Of course you didn't. Use soctchbrite twisted up on the inside. Usually the most gunk is closest to the cylinder which will be very hard to reach. If you can get a wood dowel, or fiberglass tent pole, or whittle a stick - cut a notch to hold your scotch brite and twist it in the hole. If you can get access to a cordless drill - even better to spin it around and clean the walls of the valve guide. Whew. That took a while didn't it! Feels good right?
Yeah, but don't don't start feeling too good about your jury rigging skills - you still need to get this thing back together. Now you have a valve rattling around in your cylinder. Make sure you lube that sucker up with Marvel, or KY or whatever you have laying around. Time to go fishing. Prepare yourself for that long list of mother-sucking, blankety-blank, piece of shit cuss words - you're gonna need them. Make a little hook out of the end of your safety wire and run it down the valve guide. Use another one to push the floss over and fish it back out through the hole God intended it to go through. Just pull right? It's go easy, right? Fat chance sucker. Prepare yourself for reality. A lot of fiddling will get her started - and you're going to break 3 pieces of dental floss before you realize that thing is tighter'n a frogs butt. Hmm... Get her lined up as best you can - and use your rope trick again. Go easy. Feed in as much rope as you can in there and try to keep it behind the valve. Press against the back side of the valve with the cylinder by pulling on the prop. Remove the rope and reposition it if you need to as it goes in part way. Get it all the way back out. All the way.
Now time to re-assemble the rocker and springs. Use your handy dandy valve spring-a-ma-jigger to get the springs on and compressed while you try not to sever a digit trying to get the springs in. You need at least 1 other set of hands - hopefully you're not alone. Lube up the rocker arms and reassmble both the intake and the exhaust. Clean all your spark plugs - especially the bottom ones - cause they're probably fouled up with a lot of lead deposits. Put the right anti-sieze on it - if you have it and torque - if you have a torque wrench the spark plugs. Finish your beer. Have another if you need to.
Pull the prop through and make sure she's freed up and the valves are operating. All good? Fire her up. Do a run-up. Have the sober pilot take her for a few laps around the pattern in case she wants to go tits up on you in air. Now toss all your camping gear and moose antlers back in the plane and fly her the 12 hours home - including 45 solid minutes of VFR on top of 200ft overcast - in a 1946 J3C that had a stuck valve only an hour ago.
Then clean your undies....
Thank you SO much to Mr. Mike Therm, of Rushford, MN - owner of a beautiful Fairchild for passing along tribal knowledge of the Rope Trick. This fine gentleman saved my hide, and if you are ever in the area - please, please, please stop into this GREAT little airport and spend some money on their cheap avgas and say hi.
