important info maintenance mags and charging system service bulletins
Here are some recent issues that need to be dealt with at the 500 tach hour mark or sooner. My sport cub is serial # 6 and has turned 700 hours. I have recently had to deal with the following.
1. After 300 tach hours on the Sensenich Composite Prop we had a broken prop bolt. The hub was sent back to Sensenich and they replaced it with a newer designed hub, all warranted. They were excellent to work with and very accommodating! I mostly run the 46 and the 48 cartridges however the 50 cartridge was in use for the trip to AZ from WA when the bolt broke and that's how I discovered it by taking the spinner off to change the cartridge here in AZ. The annual and last prop bolt inspection was only 15 hrs previously.
2. The mags are suppose to be rebuilt at 500 hours, mine were massaged buy not rebuilt due to being busy and then the move to AZ. Consequently at 700 hours the left mag failed. The mags have to be sent out to a certified mag rebuilding specialist. Fortunately there is one here at my new home base Falcon Field in Mesa AZ. It costs $375 for each mag rebuild plus a couple of hours labor R&R and timing for each mag. In my case I had to buy a mag core at the cost of $200. A new mag costs around $1200 each plus labor again! So you can do the $ math and see it an expensive cost. But it has to be done and done correctly by a certified mag re-builder! Its a life safety issue when you start losing mags! Both mags work perfect again!
3. Middle of December the field CB started popping and I would recycle it and it would start charging again. I would watch the voltage on the GPS. Sometimes this happened 2 or 3 times per flight other times not happen at all. Obviously an intermittent problem. I checked the alternator fuses underneath the panel along with wiring connections for the relay and the regulator for looseness or melting conditions but it all appeared ok .Finally it got to the point of not charging at all and running the battery down and losing electronics, radio first.
I had a lot of conversation with Pete Dougherty at CC I want to thank Him for all his time and input keeping us on the right track and pointing us the right direction to solve this intermittent issue!
The first thing that was discovery was major slop movement with the alternator and once remove it was discovered the coupling bushings were wore out ruining the shaft and the hub. The alternator was sent to B&C for rebuild and they also had a hub core. But that wasn't the only problem. It turns out the carbon fiber battery box was arcing against a battery terminal causing an intermittent short! ( also just reported battery box arcing was Russ Luigs sport cub #6 in Texas) Yet another problem was the original regulator was bad, this regulator is up on the left side firewall and wired direct. The replacement regulator, (which was replaced by B&C with a new regulator in Dec 2007), has removable connections so some rewiring was necessary. Now the monitored voltage is a rock solid consistent voltage and does not vary!
I want to thank Bill at B&C for assisting in the trouble shooting, we spent a lot time on the phone working through all the issues.
OK, so be sure to read very carefully the attached required bulletins and comply so you can save yourself a lot of grief and considerable $!
It is further recommended anytime you have the cowling off reach over and move the alternator back and forth checking for play. My alternator moved from ten to two o'clock and should have only moved a few degrees. You can use a magic marker to record the present movement so you can see immediately if it is increasing. Check your battery box for signs of arcing ever so often also.
A new alternator costs $530 whereas replacing the controller bushings is only a few dollars!
You probably will get some official notice from customer support at CC.
The above experience not only hit this retired guy with some serious $ but I also lost over a month of flying time which as a CFI was a considerable loss of income. I am sharing this not as sour grapes but to make you aware of these potential issues so that you can avoid the same problems and associated costs!
I love my sport cub and fly it several times a week and every time I do I feel so privileged to own such a wonderful aircraft that can do so much. Even though the carbon cub outshines the original S1/S2s they are still an awesome performing aircraft! I tip my hat to Jim R. and the CC family for developing such a standing tall and alone areoplane in the cub clone industry!
Re: important info maintenance mags and charging system service bulletins
From John Dozier AP for Russ Luigs Bandera TX Sport Cub #46..I think around 300 hours
Replacing the relay and the burned wire solved the
problem.
I looks like a poor crimp on the push-on terminal at
the relay end of wire #MB01A10BK caused the entire
house of cards to tumble. I replaced the wire with
aircraft type tefzel wire in 10 ga., terminals
crimped with Midland Ross ratchet type crimp tool and
then soldered.
John.
VIR PRUDENS NON CONTRA VENTUM MINGIT
A few of us early ones used to blow the fuses from the alternator till pete had us change over to a marine/auto type fuse and fuse holder and no problems since...Geo
"We have around 2500(Hobbs clock) hours between the 2 airframes , all of it training."
Thank you very much for your info , we have been lucky with alternators so far but will certainly check. From our experience keep an eye on the port side stabiliser for signs of fabric damage jus behind the LE tube, there is a diagonal brace in there that has become un attached on BOTH of our aircraft.
This also happened to Jon Hick's S2 previously reported on another post.
Re: important info maintenance mags and charging system service bulletins
Here is a response from Bill Farmer, Georgetown, TX owner of S2 #55
I knew about the mags, but not about the coupling s/b. I have already replace both mags with new, got my Sensenich after the recall and “fix”, use the 48 for showoff, the 50 for all normal flying. Have a 52 but it takes so much power to pull it that the extra speed isn’t worth the fuel burn. On a trip to LA the 52 doesn’t save any time because of the extra fuel stop. (I run the guts and feathers out of mine)
Developed a vibration, sent the prop back and Sensenich said they didn't understand how it go out of the factory with that much imbalance, supposedly fixed it. Really nice people to deal with. Still vibrated.
I tried to do a dynamic balance but the spinner back plate is so flimsy that the added balance weights (only place to add weights on a Continental is on the spinner back plate) would make the whole spinner assembly wobble all over the place and drive the balance instrument crazy. Also the spinner wasn’t true, out at least 3/8” at the tip and that didn’t help anything. So for a mere $600 I got a new spinner and back plate from CC. With their approval I put a .020” doubler on both sides of the back plate.(I have dwgs and parts) That stiffened it up, balanced with no problem but still have a vibration I can’t find.
I installed the larger oil cooler and that helps. Installed a four probe CHT to help with leaning. Have been to Continental Factory twice, one time to the Continental Advanced Engine Course of 40 hours. I have heard every theory about leaning there is and some I think that were just made up. Continental says(carburatored engines) turn off one mag, lean to rough, richen back up to smooth, turn other mag back on, go for it. That makes my CHT 400 or better so I lean to 380 CHT on hot cyl. Takes a while but works.
Also I cannot get the sleeve into the bottom of the airframe fuel drain line to comply with the S/B and am having a problem with Ethen at CC as to a fix.
Put the “winterizing kit” in this week, that sure helps.
I had a N3N for years and maintain 2 Stearmans, so this Cub maintenance is a piece of cake.
358 hrs and climbing,
Bill
Hanger bolts for “4 into none” exhaust. Third set in 350 hrs.
Check the hole size in the exhaust clamps that these bolts go through. If they are 1/4 inch, they need to be replaced. They should be 3/16. If there is too much play of the bolt in the clamp hole it will wear the bolts out surprisingly fast.