uk_figs

uk_figs

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I have a ECI 0-360 that has had a very small oil leak which looks like it is coming from the crankshaft oil seal, I have put up with it for quite a while but will have the opportunity to change the seal in a couple of weeks when I have the prop etc off to change the prop spacer. In checking online it seems there are multiple versions of this seal so how do I check which one I need to order.

I understand the solid version can be a pain to install so was thinking about the split version, I have a copy of the Lycoming service bulletin for the installation instructions and the adhesive.
Thanks
 
nose seals

The Standard one piece seal is the LW13792 at 11.70 or the split seal LW11997 for 33.45. I don't think the one piece is too hard to install and it would have less chance to leak at the seam.

Jesse
 
If you want to use the standard one-piece version but do not want to pay the high price for the genuine Lycoming ST-383 tool, here is a link to one that you can make. I am planning on making one and trying it out on a crankshaft that has not yet been installed in an engine. Been saving the link for when I get around to it.
 
Its very easy to replace a one piece seal. I just did mine a couple months ago. Use the Doe 737 natural cure sealant as recommended by Lycoming. After removing the old seal, clean the sealing surface of the case of all old sealant and thoroughly clean and dry the surface with acetone. Make sure you clean the grove in the case where a rubber ridge on the new seal will engage. Wipe it out and dry it several times so there is not a trace of oil! Get some HEAVY packing tape and wrap the prop flange with it. Take your new seal and remove the inner spring. Don't loose it! place the seal in some boiling water for a few minutes to soften it up. I used a microwave in my hanger to heat the water. Work fast now. Remove the seal and dry it off real good. Use a polished round 1/4" steel rod and run one end partially through the seal, then through a flange bolt hole, then again through the seal. Its now looped fore and aft over the flange. Make sure seal orientation is correct so when its over the flange completely, the open end the spring seats in is facing inside the case. Use another polished rod or round steel screwdriver to quickly pull and work the seal over the flange and bolt bushings. It goes over real easy when its hot and soft. Let the seal contract a hour or so back to its original size. PUT THE SPRING BACK ON NOW! It hooks together and some small dental picks ad tweezers are helpful here. verify the case recess is still clean and dry. Wipe down the outside of the seal with acetone and dry. Q tips help here. Apply the Dow 737 to both surfaces and seat the new seal. Let cure at least 24 hours and normal temps. No more oil leak at the crankshaft seal!
 
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I agree with David. Very easy to replace one piece seal. No special tools needed. I don't believe warming is necessary. I uses a couple of large round shank screw drivers as a tool and stretched slowly.
 
When I did mine (IO-360-A3B6D with a one piece seal) I put a grocery store plastic bag over the prop flange to act as the "lubricant". I was really concerned that it wasn't going to work, or I was going to wreck the seal, but it was dead easy.

I think the hardest part was getting the old seal out without scratching the inside of the opening....
 
Thanks for all the feedback

Great stuff and the other thread was very useful, appreciate it.:)
Figs
 
C/S prop?

Dave, we replaced mine on my IO-540 then later, started seeing oil on the windshield. Closer examination showed dry case around the crank seal but oil from the base of the prop. Turned out to be a prop O-ring. Check carefully if its a CS prop.

Best,
 
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