I finally took the airplane down to start the engine STC...

Being that this is a late model 180K with the 0-470U its a very straight forward conversion. (I hope)

I got the larger IO-470 balance tube installed with the help of my co-pilot. The only other modifications needed to bump up the HP to 252 are:

Upgrade the MA 4-5 carburetor to a modified P/N (Exchange / overhaul)
Swap the propeller governor for 2625 RPM unit (from 2400)
Reset the propeller blade stops
Re-mark the Tachometer




More to follow

Cwillfly wrote:…. I read your post after I had already installed the new wheel but sure enough I came back to the hangar and it was flat. The tube had a split/de-lamination around the valve stem. Called AA and they basically told me the same thing as you had posted regarding your friends Maule. ....

Curious if AA offered to make it right re their sale to you of a (known) defective tube?
If they'd warned you it might happen maybe then it'd be on you,
otherwise it seems like they should refund you or discount the better tube.
However, I don't recall that being the case with my buddy.

Looking forward to a pirep on the glider-tire wide fork kit.
I've heard a number of people gripe about shimmy with the fat t/w,
but others seem to have no problem so maybe it's just an adjustment issue.

I'm curious as to what prop you're running / gonna run?
I believe there's a 90" seaplane prop available for the U engine,
not sure if that's approved when they're modified to turn up to "normal" rpm's.
The tip speed might exceed acceptable parameters.

You may want to insulate that front balance tube while you have it uncowled. Find some split pipe insulation at Home Depot Aircraft Supply, wrap it around the balance (crossover) tube and secure it with tie wraps.

If/when you run into cool weather, your engine will run a lot smoother. If you’re never in cold, no worries, but it doesn’t hurt to have it done in any case

MTV

hotrod180 wrote:Curious if AA offered to make it right re their sale to you of a (known) defective tube?
If they'd warned you it might happen maybe then it'd be on you,
otherwise it seems like they should refund you or discount the better tube.
However, I don't recall that being the case with my buddy.

They did not offer and I did not ask. I was a little surprised to hear him say that it was a know problem....
Im ordering a set of 29" next week so perhaps Ill ask them to take it off of those....

hotrod180 wrote:I'm curious as to what prop you're running / gonna run?
I believe there's a 90" seaplane prop available for the U engine,
not sure if that's approved when they're modified to turn up to "normal" rpm's.
The tip speed might exceed acceptable parameters.

Im running the stock "204" propeller and luckily that is what the STC calls for. I guess that is what made the STC attractive that with a late model aircraft the modification is straight forward and relatively inexpensive. (All in less than $6,200). Its still expensive at $280.00 per HP but my motor only has a couple hundred hours on a to new tolerances and balanced engine, so there was just no way to justify the P-Ponk. Plus im upgrading to a 185 as soon as I sell enough helmets:)

mtv wrote:You may want to insulate that front balance tube while you have it uncowled. Find some split pipe insulation at Home Depot Aircraft Supply, wrap it around the balance (crossover) tube and secure it with tie wraps.

MTV, So having grown up (sort of) flying in Florida, the Caribbean, the Middle East, and Africa, I bet our definitions of "Cold" are different! At about what OAT would you consider the above to be an advantage? Thanks

Further to the previous post regarding the 4.00X4 glider tire and tube....
There is no doubt some issues with the "standard tubes that come with the 4.00X4 glider tire from ABI but they had a simple fix.

This is the tube as supplied. It inflated and held air for less than 5 minutes. Upon inspection, you can clearly see where the valve stem is de-laminating. Junk IMO

AA suggested installing a 500-4 tube to better fit the 4.00X4 when used on the spacer. They sell it but I was able to get it from Aircraft Spruce for about $30 less and had it the next day.
https://www.aircraftspruce.com/catalog/ ... _500_4.php

The hack is that the valve stem in the larger tube comes out in the middle and does not line up with the notch in the ABW spacer


Luckily, the material that the spacer is made out of machined easily. it needed to be clearanced back about 1.00"

Have they rectified the problems with the 400x4 Glider Tire talked about here?

http://www.supercub.org/forum/showthrea ... lider+tire

JamieG wrote:Have they rectified the problems with the 400x4 Glider Tire talked about here?

Based on my phone conversation It did not sound like it. "There have been some quality issues with the 4.00X4 tire and tube"

Has anyone tried this tire per the super cub site?
https://wingsandwheels.com/aircraft-par ... -8-pr.html

Although you would not guess it from the photo, I made good progress over the weekend. New fuel sending units are in and working (and not leaking) and the new 2625 RPM governor is installed. I dropped the propeller off at the prop shop for the angle change today and when I got back to my office the FedEx guy had delivered the 29s" !!

Re: Insulating the front crossover tube, Any temp colder than about zero is apt to cause uneven distribution and a rough running engine. It may not be bad until colder than that.

Even though you normally don’t fly in cold temps, one never knows what opportunity/responsibility might come up next week. Insulating the crossover is cheap and easy with the cowl off. PITA if you have to do so on a ramp in the cold.

FWIW.

MTV

Cwillfly wrote:…. Has anyone tried this tire per the super cub site?
https://wingsandwheels.com/aircraft-par ... -8-pr.html

Tost also sells a 400x4 tube for their 400x4 tire:
https://wingsandwheels.com/tube-400x4.html

Their tire is spendy but the tube is cheap.