Rotax 503 / 582 Crankcase sealing surface cleaning

This is the damage free cleaning method I use. It’s extremely important to preserve the sealing surface integrity of the crankcase.

[@aerocam2]

Thank you so much! For some reason, despite having a 20# box of crushed walnut shells sitting Bach in the shop for 6-7 years, I’ve never used them nor I have thought to use them to lean case halves. Betcha I do next time. We so appreciate your videos and the information you share. Thank you so Much!,

[@RotacRepair]

Your welcome. Mmmm, I would imagine the next 20# bag will be more expensive than that one. Happy flying!

[@richardturner6278]

Thank you for sharing all the information you do. Very informative and helpful. I have great success using starting fluid and a paper towel to get most sealants off aluminum components. It's a little slower but it does work if u don't have a walnut blaster. It just simply melts the sealant and it usually just sorta rolls off. Then go back with brake cleaner to prep for final assembly. Now I will say that all starting fluid is not the same. The key is the ones with the highest either content. Over the past few decades the either content has been lowered across the board for safety and environmental concerns I'm sure. Diesel fuel or kerosene ( which is almost identical) works great also but just messy to deal with. Now I'm not suggesting anyone try any of this. But it does work and we've been doing it for ever around here. Another option for someone is to just take the part to their local engine shop and have them clean it. The main goal, as you pointed out, is to get the part absolutely clean and oil free with no scratches. Anyway, thanks again for sharing your expertise.

[@RotacRepair]

There’s always more than one way to get there. I hadn’t thought about using starting fluid or diesel. I. Your method certainly has been successful for you and won’t scratch or harness the surface. Thanks for the tip.

[@seangreene64]

Ceramic scraper or plastic utility cover plate works as well 11:49

[@RotacRepair]

Two good suggestions, Thanks for the tip

[@challenger2aircraftadventures]

Once all that cleaning and such is done. What 2 stroke oil would be best for engine protection, where the engine has oil injection. I keep getting all sorts of advice from people who I'm sure mean well, but coming from someone who rebuilds engines and knows what does the least damage is my preferred source of information. I do have a feeling that this may be a bit of a controversial topic, kind of like which beer is best for a summer time BBQ. Cheers from Winnipeg.

[@RotacRepair]

Controversial is correct! I personally use Castrol Super Snowmobile 2T. I find it has great corrosion resistance, mixes easily with neat gasoline, E10 and 100LL, it’s readily available in my area and is reasonably priced. The 1 litre container part number is 0017442, the 4 litre container part number is 0017431. Everyone is welcome to use their favourite flavour of oil, however when I’m directly asked, this is my recommendation.

[@donsipes]

Thanks John. Good episode. A couple of questions: What's your take on vapor blasting? I'm not sure what the medium is but I hear good thinks about it! What do you do when the guy before you has not been as diligent and surfaces are scratched up? CHEERS!

[@RotacRepair]

I’m not very knowledgeable about Vapor blasting. I’ve seen what I would consider good and poor results, I’m sure it is dependent on the secret recipe of blasting media. It’s interesting to note that the walnut shell will easily remove carbon from the piston dome and ring groves, however it’s gentle enough to not remove the magic marker where I’ve written on the piston skirt. Quite amazing!

[@RotacRepair]

If the crankcase sealing surface has been damaged by abrasive cleaning it’s pretty much scrap. While the low areas may initially seal at assembly, there’s a good chance that the unsupported sealer areas could blow out. Then the resulting lean mixture could be fail the engine. The crankshaft bearing crush may also be affected. I wouldn’t risk it, cheaper in the long run not to use a crankcase with damaged sealing surfaces.