Since the 3/8" drive is in line with your wrench adapter, I don't *think* you need to turn your wrench at a 90. The drive isn't extending any, it just goes around something. Glad to see another of your videos. I don't have a Frank in my Stinson, but always cool to learn about them. Thanks!
You are correct about the center line. Mine are fairly close being custom made. This rule is more for crows feet and torque adapters. Thanks for pointing it out.
Good stuff. I have a '46 straight-108 with the Franklin 6A4-150-B3, based on a private airpark west of Bremerton. My wife and I are in central BC, having been on our way to Alaska last week when we lost a cylinder and diverted 50 mi to a small airport. Turned out to be a broken intake rocker arm on the #5 cylinder - this is one of the early 150s that used stamped rocker arms vs the later 150s & 165s that used forged. Valve wasn't stuck, pushrod not bent, rocker arm showed polishing along the crack line which makes me think it developed over a while. I was able to source a replacement rocker arm only 90 mi away, but the mechanic who brought & installed it isn't familiar with Franklins, and we had a hell of a time getting the lifter depressed on the exhaust valve side to get the clearance set correctly (granted, without your handy tool). We got it close enough and I flew to his shop, engine ran slightly rough at times. This morning he made up a better tool and was able to depress the lifter enough to set the .040 clearance correctly, and on test flight engine ran much smoother. Curious if you've seen much variability between your various lifters. I'm wondering if this one being so stiff is due to being gummed up with carbon or whatever, and if this might impact oil delivery to the rocker arms. Maybe hastened the failure? Above aside, we decided not to continue north to Alaska. Engine only has 100 hrs SMOH and the failure gives me qualms about taking it anywhere too remote until it's proven this is a one-off.
As with most older aircraft and engines it's a risk you taking flying an older vintage aircraft on a long trip. Even after an Overhaul I always prefer to fly as many hours as possible. I am a very big proponent of Mike Busch's philosophy of proof of operation ( If it ain't broke, don't fix it ). If you have got to the trouble of finding that rocker you no doubt ave looked at the others. If you are that far intern Overhaul I would be less worried than if you had say 20 or 25. By the 100th mark most of the egregious errors pop up as you have noted. That should be some reassurance. As for the lifters, there are a couple different styles. The Stinson Franklins share a lot in common with the Helicopter motors. Some of those internal parts are interchangeable and some are not. As I understand the 2 styles I have seen are interchangeable, I have both in Shelia. I ask that question early on with Susan @FranklinEngines , and she assured me that they were. Regularly checking those clearances ( 200 hours is the interval ) will keep your engine purring. I hope that you have agreeable weather and have a safe journey. Christopher
Yeah, I don't know of anybody that sells the Franklin Cylinder wrenches due to the square angle that's needed to get around the fins. I would recommend around a 12" length and a 5" depth. Try to keep them concentric, so as to not need any torque corrections.
@@FreedomfixerFlying cylinders are 88.5mm (about 3.5 in). Another question, do Franklin engines have cylinder studs that are also through bolts on the case (like the 'other' airplane engines)? Is there the same risk of spun main bearings after cylinder work?
Since Airworx got out of the Franklin business, I currently do not have a shop. You can contact Susan Prall at Franklin Engines in Jewett Tx, Franklin Aircraft Engines in Ft. Collins Co or Franklin Aerospace in Thomasville, NC.
@@FreedomfixerFlying I know a guy with a Franklin 180 who keeps a whole top end on a shelf... and he uses them often. I may send three this time. I do have an extra.
Since the 3/8" drive is in line with your wrench adapter, I don't *think* you need to turn your wrench at a 90. The drive isn't extending any, it just goes around something. Glad to see another of your videos. I don't have a Frank in my Stinson, but always cool to learn about them. Thanks!
You are correct about the center line. Mine are fairly close being custom made. This rule is more for crows feet and torque adapters. Thanks for pointing it out.
I'm flying with a Franklin 6A-350-C2 on a C175. Thanks for this informative video! Best regards from Switzerland
I have a friend here with that motor in his Velocity. We have lots to talk about.
Good stuff. I have a '46 straight-108 with the Franklin 6A4-150-B3, based on a private airpark west of Bremerton. My wife and I are in central BC, having been on our way to Alaska last week when we lost a cylinder and diverted 50 mi to a small airport. Turned out to be a broken intake rocker arm on the #5 cylinder - this is one of the early 150s that used stamped rocker arms vs the later 150s & 165s that used forged. Valve wasn't stuck, pushrod not bent, rocker arm showed polishing along the crack line which makes me think it developed over a while.
I was able to source a replacement rocker arm only 90 mi away, but the mechanic who brought & installed it isn't familiar with Franklins, and we had a hell of a time getting the lifter depressed on the exhaust valve side to get the clearance set correctly (granted, without your handy tool). We got it close enough and I flew to his shop, engine ran slightly rough at times. This morning he made up a better tool and was able to depress the lifter enough to set the .040 clearance correctly, and on test flight engine ran much smoother.
Curious if you've seen much variability between your various lifters. I'm wondering if this one being so stiff is due to being gummed up with carbon or whatever, and if this might impact oil delivery to the rocker arms. Maybe hastened the failure?
Above aside, we decided not to continue north to Alaska. Engine only has 100 hrs SMOH and the failure gives me qualms about taking it anywhere too remote until it's proven this is a one-off.
As with most older aircraft and engines it's a risk you taking flying an older vintage aircraft on a long trip. Even after an Overhaul I always prefer to fly as many hours as possible. I am a very big proponent of Mike Busch's philosophy of proof of operation ( If it ain't broke, don't fix it ). If you have got to the trouble of finding that rocker you no doubt ave looked at the others. If you are that far intern Overhaul I would be less worried than if you had say 20 or 25. By the 100th mark most of the egregious errors pop up as you have noted. That should be some reassurance.
As for the lifters, there are a couple different styles. The Stinson Franklins share a lot in common with the Helicopter motors. Some of those internal parts are interchangeable and some are not. As I understand the 2 styles I have seen are interchangeable, I have both in Shelia. I ask that question early on with Susan @FranklinEngines , and she assured me that they were. Regularly checking those clearances ( 200 hours is the interval ) will keep your engine purring.
I hope that you have agreeable weather and have a safe journey.
Christopher
Great to see you back. Looking forward to seeing Sheila back in the air 🙂
Thanks, Glad to be back flying. It's been busy dealing with this cylinder and having a late summer didn't help much. I appreciate your support.
super cool, dude! Great to see Sheila flying again!
I'm so glad to have her back! The next ones to come have a special place for me. Spoiler,... Sun River Or!
@@FreedomfixerFlying Sweet! When you're ready for some fall pics, lemme know!
Hi great video. Can you share dimensions of the cylinder nut tool. Just received my 6 cylinder overhaul but don’t have the tool. Will make one. Thanks
Yeah, I don't know of anybody that sells the Franklin Cylinder wrenches due to the square angle that's needed to get around the fins. I would recommend around a 12" length and a 5" depth. Try to keep them concentric, so as to not need any torque corrections.
Really neat! New LSRM, working towards A&P, always thought the Franklin engines were cool.
It's too bad the Type Certificate holder is in Poland. It would be nice to get new parts.
Great content! Thanks for sharing.
You are welcome. Thanks for watching.
Great info. !
Thanks.
My VW bug ring compressor is just like yours!
The ring sleeves must be pretty small. What diameter are they?
@@FreedomfixerFlying cylinders are 88.5mm (about 3.5 in). Another question, do Franklin engines have cylinder studs that are also through bolts on the case (like the 'other' airplane engines)? Is there the same risk of spun main bearings after cylinder work?
That is the largest feeler gauge I have ever seen!
They are machinist gages. I got them years ago from Brand X. I'm not sure how to replace them.
Looks like a nice easy engine to work on do you like the Franklin engine a lot more then say a rotax
I haven't worked on a whole lot of Rotax. I pretty much stick to the certified stuff. I have wanted to take a factory class on the Rotax.
Nice and helpful video. Who did the cylinder rebuild and what did it cost?
That was a Airworx job. He's out of the Franklin business now. Call Susan @Franklinengine
Wouldn’t you need to drain the tappets in order to accurately check the rocker arm clearance?
That is what the tool does, It depresses the rocker. And there is a small hole in the lifter where their escapes.
Cool video, just wondering is not there a Franklin Repair/Manufacture shop in Alabama? Not sure but I seem to remember Brewton?
Yes there's Airworx in Brewton Al., and Southern Aero in Carolina. Everybody else out west are independents.
I have a Stinson 108 with 150 hp. Franklin where did you send your cylinder to be repaired?
Since Airworx got out of the Franklin business, I currently do not have a shop. You can contact Susan Prall at Franklin Engines in Jewett Tx, Franklin Aircraft Engines in Ft. Collins Co or Franklin Aerospace in Thomasville, NC.
@@FreedomfixerFlying thank you
At least one a year. This year I get to replace 2 ✌️
Oh, man that's too bad. After 6 you should be good, right?!?
@@FreedomfixerFlying at 150-200 hours a year after six it’s time to start over at 0. 😂
@@GreatMichiganBushCo You should start keeping spares on the shelf at that rate!
@@FreedomfixerFlying I know a guy with a Franklin 180 who keeps a whole top end on a shelf... and he uses them often. I may send three this time. I do have an extra.
@@GreatMichiganBushCo I found a core motor. Working on the tear down. It's crank broke but 4 of the 6 are in decent shape.