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Post Trip Report

kaweeka

Well Known Member
My 3 month sabbatical turned in to a brief 3 week flight from Sacramento, Ca to Guadeloupe then back after Covid 19 showed up. It's amazing how fast everything spiraled down the drain. We spent 4 days in Antigua then flew 52 miles to Guadeloupe to find the entire island shut down. At that point we figured we better get back to the US before everything closes everywhere.

All in all the experience was great. The plane flew flawlessly. About 7500 miles in all. After I got back, the world changed (in just a few weeks). I'm back seeing patients on a limited basis and volunteering to work the in the ICU. It's been a few years since I had to manage a vent but it's amazing how fast that knowledge comes back.

There are a few things I noticed, however.
1) I need to change the front crankshaft seal. Watched videos and read a lot. Seems pretty straight forward. I ordered 2 seals just in case I muck up one! Saw a tool I can make and spoke to one fellow who uses bicycle tire plastic irons.
2) I was supposed to stop at AFP for some individual tuning with Don but for obvious reasons, could not. When this mess is over I would love to get with someone closer to Northern California who knows the system and would spend some time on this. The plane runs great but I think we can get better and the experience is invaluable.

Please, everyone, heed the social distancing. Be safe. I see this up close and personal. I hate to think anyone got sick who could have avoided it. Happy Easter,
David
 
David, I just want to say thank you for volunteering in the ICU. With as many doctors who died in Italy, it's obvious that choosing to do this is putting your life on the line. It is truly a BFD that you and all of our health care workers are there on the front lines. I barely know how to put on a band aid, so I'm in awe of all of you.Very sorry that you didn't get to finish your trip but I surely hope you get a second opportunity!
 
Front Seal

A seasoned AP/IA (he is in his 80s) gave me this advice on installing a front seal. Cover the flange with a zip lock bag. Grease and/or oil it up. It provides a very smooth and slick surface to avoid nicking the seal as you lever it over the flange.
Don
 
Thank you for volunteering in the ICU. If you want to do injector tuning yourself, it is not hard. Fly at normal cruise altitude and power settings, then record fuel flow, and EGT for each cylinder, as you slowly lean. Be sure you capture FF and peak egt for each cylinder. Send the data to Don, he will recommend and sell you several replacement injector nozzles. They are not difficult to swap. Repeat the test flight and decide if additional fine tuning is needed.
 
before trying to streach the seal over the flange, make sure you inspect the flange real close for any (even very small) nicks. dress them out fully. it only takes a very small burr to nick the seal an trash it. the zip lock bag trick works good. here i florida, I set the seal out in the sun for while to get it good and warm before i install it.

bob burns
RV-4 N82RB
 
Thanks for helping out David. A couple things to have on hand before you start is the new crankshaft seal, along with a tube of Dow Corning 737 Natural Cure Sealant. https://www.lycoming.com/sites/default/files/Crankshaft Oil Seals.pdf I have changed a few nose seals out and found that wrapping the crankshaft with packing tape instead of a baggie works better for me, but either will do. You will want to use some hook style picks to get the old seal out, remove the internal spring very carefully so it does not come apart and pop into the crankcase, cut the seal in half and remove, then clean the case opening thoroughly using some dental picks and mirror. Get all the remaining sealant off the contact area and no oil or anything on the case sealing area. Acetone works good to dry up any oil. Clean and dry it several times.
Remove the internal spring from the new seal so you will not overstretch it or damage it during the installation process. It just hooks together at the ends.
Heat up a pan of very hot water and when you are ready to go, put the new seal in it for a minute or two to soften it up. Have a couple 3/16" or 1/4" diameter polished round rods on hand to help work the seal over the covered prop flange. Phillips screwdrivers work good. They can't have any nicks or scratches on the rods as that may catch and damage the new seal. You could also wrap those rods in packing tape as a precaution. When you are ready to go, work quickly as the seal will cool and harden back up quickly. You can lubricate the taped up flange with oil but then you have the issue of removing it off the seal completely afterwards. I don't lubricate and if you do it quickly, the seal stretches and goes over without it. Careful with orientation of the seal when you begin. You don't want to install it backwards. Quickly remove the seal from the hot water and work it over the flange and the prop bolt lugs using your tools. Looks impossible to stretch the seal that large but it does stretch! Once over the flange, I let it sit a few hours to return to its original diameter. Cut a piece of thin cardboard to slip over the crankshaft that will cover the opening of the case. The spring is a bugger to get back together and installed in the seal again and you are working right up against the opening. You don't want it to slip, spring, or fall into the crankcase as you are trying to reinstall it.
Clean up the seal and crankshaft surface one more time to ensure everything is dry and 100% oil free. Carefully lube up the crank shaft with a small acid brush behind the new seal. Apply Dow 737 sealant with a small acid brush as directed. When its time to push the new seal in place, make sure it is straight and fully seated. The case has a small ring in it that fits into a slot on the seal. Clean up access squeeze out and let fully cure before running the engine. A fun project.
 
Dave----you can fly over here anytime you want. Sorry we couldnt get together, but we will.
Bob Turner said it right, get your Savvy data and send it to Don. He'll do his magic thing and send you the new nozzles
 
Another option for injector tuning is to run the Savvy flight test profile, upload the data to their website and check the GAMI spread using their free tools. You can also sign up for their Pro service and have someone on their team analyze the data for you.
 
Mask the crank flange edge and bushings with 1-2 wraps of 2" masking tape.

No oil. No ziplock bag. They just make things harder.

I use a large round phillips screwdriver in one of the crank bushings to capture the seal and a large square sided Craftsman screwdriver to pull the seal around over the flange. I have the proper Lycoming tool but never use it as it scratches the flange.

It takes me no more than two minutes to do the task of getting the seal over the flange. Do 4-5 of them a year.
 
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Thanks all for the advice. It matches up with everything I've read. I bought 2 seals....just in case, as well as the Dow sealant. I will let y'all know how it goes. Thanks again. What a great community!!
David
 
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