Oil - not good

wayne

wayne

Pattern Altitude
Gone West
Joined
Mar 10, 2007
Messages
2,391
Location
Atlanta, GA
Display Name
Display name:
wayne
Got this pic from a partner. Said he saw some oil spray on the windshield when landing in Nashville today. The plane just finished annual a week ago on Friday, and this was the first flight.

Looks like my wife and I will be driving to Charleston on Tuesday instead of flying. :(

Plane Cowl Oil.jpg
 
Had that happen on my Glasair. Mech split the o-ring when he reinstalled my CS prop. Had oil streaming back on the windscreen.
 
That looks more like a failed crank seal. A failed prop o-ring should leave oil on the prop blades and spinner.

Was the seal changed at annual?
 
Hopefully something to do with oil P/T sender or plug, or cooler...something that can be fixed cheaply!
 
Dan Thomas said:
That looks more like a failed crank seal. A failed prop o-ring should leave oil on the prop blades and spinner.

Was the seal changed at annual?
Click to expand...

I don’t think so, need to relook at the annual statement.

That was just over an hour flight to Nashville.
 
Bummer
 
Sorry to see that.
What kind of plane is it? And is it hard to remove the upper cowl?

I would want to take a look asap.

Glad he got it on the ground safely.
 
What’s involved in replacing a crank seal in a Lycoming/Continental (besides money)?
 
455 Bravo Uniform said:
What’s involved in replacing a crank seal in a Lycoming/Continental (besides money)?
Click to expand...

Big picture for a lycoming:

Step 1: Remove the prop.
Step 2: Use a pick or similar tool to extract the old seal. Cut it with a pair of wire cutters or similar to remove.
Step 3: Clean the recess where the seal fits.
Step 4: Either install a split seal (easier) or an un-split seal in the gap. Getting the un-split seal over the crank flange is a job - you heat the rubber seal, remove the springy wire from it, and stretch it over the crank flange (which you coat with tape to reduce sharp edges and maybe make it slicker). You secure it in place with adhesive.
Step 5: Reinstall the prop, alternator belt, etc.

I've never replaced a seal, but just removing and reinstalling a C/S prop is a rotten job because they are heavy and the way they attach requires the patience of Job to tighten all the bolts one flat at a time.. Replacing the seal is insult to injury.
 
Rgbeard said:
as little as an ounce of oil looks like a murder scene on a cowling.
Click to expand...
Just like blood.

Can the split seal be installed without removing the prop?
What's the "success" percentage of split versus un-split?
 
Domenick said:
Just like blood.

Can the split seal be installed without removing the prop?
What's the "success" percentage of split versus un-split?
Click to expand...

Can't answer your questions about the split seal. Here's a video of replacing the un-split seal. (Run it at 1.5 speed and you'll be fine).

 
It's a Continental. The plane is a Cirrus SR22. So, it's a IO-550.
 
Cool vid, thx for sharing. Would have been nice to see up close, but good enough to understand.

So is there no seal cover plate, to keep dirt out or the seal from walking forward?

Sorry to hijack the thread, I can’t help myself.
 
Go to the Continental M-0 Standard Practice Manual, to Section 10-10, Crankshaft Nose Oil Seal Replacement. http://pceonline.com/wp-content/uploads/2017/04/M-0standardpractice2017-01-15.pdf

Note that there is a specification for the sealant used on the seal. There's a table in Section 3 that tells you what the Continental part numbers for the sealant and primer cross to; they're Loctite products. Note also that they ARE NOT RTV. Some mechanics are fond of RTV, and it can cause serious headaches. There is a drain hole in the seal bore in the crankcase that drains oil that comes off the crankshaft front bearing back to the crankcase. RTV has a nasty habit of gobbing its way into places like that, blocking the hole and allowing oil pressure to build behind the seal and blowing it out.
 
A couple tricks to installing the one piece seal on a Lycoming:

Have a microwave handy to heat the seal in some hot water for 5 minutes or so.
Put a plastic baggie over the flange and give it a good coat of oil
Use a long 3/8 extension with a a nice, round polished shaft to work the warm seal over the flange.
5 minutes.

The real trick is safety wiring the prop bolts. That takes a bit of finesse. Depending on the prop, you may need to make a special wrench to get the bolts off.

Oh, and if you have an alternator, perfect time to replace the belt.
 
You must log in or register to reply here.
Back
Top