Yearly Archives: 2023


Nose Seal: Part deux   Recently updated !

Much as I did with the oil cooler bypass valve, I wanted to get a head start on replacing the nose seal tonight by removing the spinner, prop, and flywheel. Then when the new nose seal arrives I can be ready to go.

First I removed the spinner and the propellor. Then I loosened the alternator belt and removed the flywheel.

This is where it gets interesting.

I wanted to inspect things carefully – as I wasn’t 100% convinced the source of the oil was the nose seal.

So the first thing I noticed, was the face of the engine behind the flange was dry. If the oil was coming from the nose seal… this is pretty unlikely. The pencil is pointing to the dry location.

This area (indicated by the pencil) is also dry.

Now the flange itself has a good bit of oil on it, including some fine blackened oil particles. You can see the oil spray in the next 3 photos. Now, the oil all over the rest of the engine has not been black, but clean mineral oil. I suspect this is just what is left behind after running a full speed.

At this point, I’m fully suspicious that the culprit is the o-ring to flange seal, instead of the crankshaft nose seal. Inspecting the flange shows some very minor scoring where the o-ring would sit. Shown in the next photo.

Here is a close up. The scoring looks worse in this photo than it is. With your fingernail this is barely noticeable. But still its there.

Just a little bit of scotchbrite action resulted in the following photos.

You can also see evidence of the oil show in black here on the inside of the flywheel.

Now I decided to do one more test to confirm that the nose seal is in fact not leaking. I took a clean papertowl and ran it down along between the crankcase trigger wheel and the nose seal. Directly making contact with the crankshaft and the nose seal. I did this all the way around the crankshaft.

The result was a completely clean and dry paper towel. I cannot imagine that the papertowl would be clean if the nose seal was the leaking problem. In which case, maybe it never needed to be replaced to begin with.

This means that my likely culprit is the hub to crankshaft flange intersection. I set about doing a thorough inspection of both the hub, the o-ring, and the flange. The o-ring and hub both looked immaculate. The flange had some grime, and the minor scoring shown earlier. I used some scrotbrite and some solvents to thoroughly clean the flange and the mating surfaces. I’m also going to get a new o-ring while I’m at it. Fingers crossed!


Induction snorkel & oil cooler bypass

My first project for this afternoon was to fiberglass the hole in the snorkel I cut previously to provide more relief where it was rubbing the cowl. Unfortunately, no pictures. Its hard when you’re doing fiberglass and your hands are all messy to remember to take photos. But not much to report. I put fiberglass over the hole. Job complete.

I’m going on vacation soon – caving in Tennessee – and I’m also waiting on several part orders for the airplane. In the meantime, I can start breaking things down to prepare for the parts when they arrive.

First on the docket – the leaking oil cooler bypass valve. This baby is 1 1/4″. I didn’t have a crowfoot wrench or offset big enough. And there isn’t clearance for a socket. A little creativity and I was able to get it started with an adjustable wrench and then work it out using the remaining safety wire of all things.

The cause of the leak was immediately apparent. No gasket had been installed!

Here is the diagram from the parts manual that clearly shows the required gasket!

My little form-a-funnel came in handy once again!.

Closer inspection showed there was even a little nick in the collar of the valve from where it had been torqued onto bare metal. I used a little file and emory cloth to clean it up.

 


Maintenance and Tuning – First report   Recently updated !

I’ve completed 7.3 hours now in N22UP since June 13th. And during that time there has been a number of maintenance issues dealt with, and general tweaks. We’ll try to hit them one by one.

After the first flight it was readily apparent that I had three noticeable issues. First, there was an oil leak off the accessory case. Exactly where, was hard to tell – as the oil goes everywhere. I wrapped a bit of paper towel around a couple suspect areas, and determined it was likely the o-ring on the prop gov oil line. Additionally, the nose seal was weeping some oil, and the horizontal induction snorkel was rubbing the cowl. None were going to cause me to fall out of the sky, but all would be dealt with. After a couple more flights, I decided it was time to deal with them immediately to save the alternator etc from getting drenched in oil.

Nose seal.

Here you can see some photos of the mess the nose seal is making spraying oil everywhere.

Replacing the nose seal means pulling the prop and the flywheel. And in my case, it also means the crankshaft timing wheel for the ElectroAir ignition also must be removed… and then retimed.

Here you can see the old nose seal as we’ve gotten it out before we cut it off. After we cut it off it took quite a bit of time to get the old bonding agent cleaned out.

Then the new nose seal goes into hot water, and then is stretched over top using a special tool.

Unfortunately, after returning the airplane to service, the latest flight shows that the nose seal – or something in its immediate vicinity is still leaking. So I’ve ordered a new nose-seal, and we’ll start chasing this down again.

Breather tube.

I don’t have a picture of this at the moment. But basically I relocated the tube further aft for its exit above the exhaust.

Prop Oil Line O-Ring.

Here’s the o-ring fitting in question. A bit of a pain in the butt to reach. After replacing this o-ring,

Here are a few pictures of the old o-ring after removal. It looks like it got mangled in the threads.

After replacing the o-ring, there is still a leak in the vicinity. Using some paper towel testing shows the leak appears to be the oil cooler bypass valve. I have a new gasket for that already enroute.

Induction snorkel rubbing cowl.

When the rubbing was first discovered, I placed some 3M double sided tape in the area to protect the parts temporarily. I cut a section out and fiberglassed in a new section with about 1/4 of relief.  

Unfortunately, that was not enough. As you can see, I now have two new areas that are rubbing. (Little black rubbing points). So, I’ll have to provide even more relief.

My approach to each point is to get a straight edge and mark a circle around each that represents about 1/4 of fall from the high point. You can see this resultant circles here.

I then cut an even larger section out than previously. I glassed over this today, and will get a photo next time I am at the hangar.

Broken wheel pant.

Turns out I didn’t trim my wheel pant to tire clearance far enough. The tire rubbed the pant enough on the first flight landing that it cracked the wheel pant and took a chunk out. I used some flox to get the cracks and removed chunk back in place.

Then i used my thicker glass weave on the inside, and my fine weave on the outside.

Lastly, I trimmed both wheel pants further, and re-installed.

Scat tube rubbing oil dipstick.

The scat tube that runs from the baffle to the oil cooler, was being problematic. It was rubbing the oil dipstick tube, and potentially the engine mount. I tried one fix – shortening the scat tube, but unfortunately I did one trim too many and lost the appropriate amount of flex needed for engine movement. So a new bit of scat was installed. This time, I decided to go dirt simple. Zip-tie plus rubber tubing offset and some silicone tape.

Oil and filter change.

I did an oil change at 6.4 hours. Since I had to pull the prop for the nose seal, I figured I might as well do it. Here you can see my methods using my awesome quick drain.

As well as my form-a-funnel for the oil filter.

I cut open the oil filter.

Mike Rollison showed me a neat trick to remove the oil filter pleats and then squeeze the oil out with a vice. Here are photos of the cleaned up oil filter pleats.

Some small bits of metal were evident. None were ferrous. Mike said this is 100% in line with what he would expect for an engine during break in. I kept the pleats so that they can be compared to the next oil change.

I also sent my oil to Blackstone Labs for oil analysis. Yes, its a bit early, but nows the time where there could be trouble. So lets see what the oil has to say.

New seats and stick boots.

I bought nice stick boots from Oregon Aero. These will protect from foreign objects getting lodged and give the cockpit a good aesthetic. I was also able to grab a set of used Classic Aero cloth seats off Van’s. The trim is blue, which doesn’t work exactly for my plane, but these will do perfectly for now. They even came with extra material and booster seats!

Brake line length reduction.

I forgot to take any before photos, but basically the low pressure brake oil lines were too long. They needed about 4″ per side removed. I also needed to then add some new protections against rubbing in place. Here is the result.

Also, a bonus photo of Squire. Because he’s awesome.