Prop Strike - 500 Hour Gearbox Inspection

[@raydreamer7566]

Well you can't get more of a test for a gearbox than a hard prop strike.... The gearbox survived with flying colors and is rebuild able great job Viking . I am glad you took on this inspection and rebuild yourself. Your learning curve has just gone straight up for the better.

[@lesb3481]

I used to be highly doubtful of my ever owning an aircraft engine with a PSRU on the front of it. This opinion was reinforced over the years by seeing the first generation of badly designed PSRU's which came with belts, chains, overheating problems, dubious reliability over time and a significant chance for catastrophic failures. However, I think that while I've been quite impressed with Viking's engines, what has also impressed me, has been the logical design of their PSRU's. In my opinion, keeping a PSRU design simple, eliminating failure prone items like belts or chains and instead having it be a direct gear drive, running in gear oil(not engine oil) inside a billet case, is the only way to obtain bulletproof reliability. This is just one more reason why it's almost certain, I'll be calling Viking when the time comes to purchase the engine for my project.

[@eggenfellner]

That is where a lot of the misconceptions are from. Glad your watching and following along. Like most things you can learn from mistakes of the past and continue to improve!

[@SuperYellowsubmarin]

Right, except for the gearbox oil vs engine oil part though. It's been proven to work (any radial engine, RR Merlin, and most recently the Rotax 91x series). You need additives in the oil though, as in a motorcycle engine (another example).

[@SeansLittleBayofHorrors]

​@@SuperYellowsubmarin Friction modifiers are only needed in motorcycle engines without separate engine and gearbox sumps. My Honda CRF450R ran engine oil in the engine, and gear oil in the gear box. Why? Because gear oil is meant to work on gears, where engine oil is not.

[@transsib]

That's impressive, the gearbox indeed still looks brand new! Great that you caught the small marks.

[@superbill9066]

I've been highly sceptical of auto conversions, but I'm coming around!

[@floridasaltlife]

Always impressed with the Viking products. I think Jan has them down to a science now and not much experimental in them these days...That is a great thing

[@Tryagain205]

Nice to see just how honest this company is; they didn’t have to show the tear in the seal and he even says that it could have been a defective seal or the issue could have been from the prop strike.

[@Uncle-Duncan-Shack]

That was great information, valuable insight into what to expect on the prop speed reducer after a strike and how important inspections are. And yes, a bearing is on borrowed time after an impact. Just replace them, they are a fraction of the cost of pulling the gearbox, just to begin with. Also that's what stands between you and a dead stick over a forest, as you said.

[@foesfly3047]

Everything about this incident lends excellent testimony to Viking Aircraft Engine design.

[@eggenfellner]

Thanks you, much appreciated

[@johngood3163]

I'm watching these on my TV, so I don't have the freedom right away to comment. I am really impressed by how you are working through this. Sure, you could perform NDI. However, I think your approach is very practical to replace these items that support the load or experience the stress and replace them for the few hundred dollars they cost. I am encouraged by this video.

[@eggenfellner]

Thanks John, it mostly comes down to replacing the necessary, if it isn't necessary, it does become the option of the owner. Things in experimental can be tricky in these circumstances sometimes.

[@rustusandroid]

That has to be the biggest cheater bar I have ever seen. Love your engines :)

[@user-hj9io8nr9w]

Cool channel!Sanks!

[@kausirkhan6173]

Thanks for good information I also trying to making gearbox I don't have too much idea so now I see this video now is easy for me thank you for make the video for 👌

[@johngood3163]

This is a great and informative video.

[@tinolino58]

SKF bearings, the best!

[@williamfahey4092]

Well done. Thank you.

[@eggenfellner]

Our pleasure! Thanks for watching.

[@michaelz6870]

The Jesus nut--I love it! :-)

[@cedricm4693]

Did you do a penetrant dye test on the gearbox and gears ?

[@radioace318la]

No jig setup to mic the rotation for roundness? Great eye, catching the stressed teeth. Cheers from Louisiana.

[@chippyjohn1]

What viscosity of oil do you use and what temperature does the gearbox see, same as the engine or cooler?

[@Georgianotthestate8894]

Nice video I have a question, when there is a prop strike that is severe can that effect the crankshaft or just the gearbox?

[@rustusandroid]

A late response, but no, the crankshaft would not be affected since the prop is not directly tied to it. In Vikings PSRU the gearbox would take the brunt, and the dampeners would absorb the rest.

[@mdmalek4003]

I need this Prats, how much prices

[@simeon2851]

8:40 Does the apprentice ever ask questions..?

[@eggenfellner]

Sadly, I've seen this done more than a few times :) Not really an apprentice -Alissa

[@simeon2851]

@@eggenfellner Oh. She looked up at you like she was about to.